Geology and Resource Assessment of the Venezuelan ... - USGS

Study Area

---

Click here for more detailed map

---

U.S. GEOLOGICAL SURVEY DIGITAL DATA SERIES DDS-46<br />

<strong>Geology</strong> <strong>and</strong> <strong>Resource</strong> <strong>Assessment</strong> <strong>of</strong> <strong>the</strong> <strong>Venezuelan</strong> Guayana Shield at<br />

1:500,000 scale--A Digital Representation <strong>of</strong> Maps published by <strong>the</strong> U.S.<br />

Geological Survey<br />

By Paul G. Schruben(1), Jeffrey C. Wynn(1), Floyd Gray(2), Dennis P. Cox(3),<br />

John H. Stewart(3), <strong>and</strong> William E. Brooks(3)<br />

(1) U.S. Geological Survey<br />

920 National Center<br />

12201 Sunrise Valley Drive<br />

Reston, VA 22092-9998<br />

(2) U.S. Geological Survey<br />

210 E. 7th St<br />

Tucson, AZ 85705-8454<br />

(3) Formerly with U.S. Geological Survey<br />

U.S. DEPARTMENT OF THE INTERIOR<br />

BRUCE BABBITT, Secretary<br />

U.S. GEOLOGICAL SURVEY<br />

Gordon P. Eaton, Director<br />

For sale by U.S. Geological Survey, Map Distribution<br />

Box 25286, Building 810, Federal Center<br />

Denver, CO 80225<br />

Prepared in <strong>the</strong> Eastern Region, Reston, Va.<br />

Manuscript approved for publication .<br />

1997

---

Title Page<br />

Disclaimer<br />

System Requirements<br />

Acknowledgments<br />

Contacts<br />

User Registration<br />

Disc Contents<br />

Project Overview<br />

History <strong>of</strong> <strong>the</strong> Maps<br />

Bulletin 2062 Text <strong>and</strong> Figures Files<br />

References for this Disc<br />

Digital Production Techniques<br />

Map Projection<br />

Cautions Relating to <strong>the</strong> Use <strong>of</strong> <strong>the</strong> Maps<br />

Online Files<br />

Graphics Formats Available on <strong>the</strong> Disc<br />

ARCVIEW 1 <strong>and</strong> ARC/INFO Files<br />

Export Files<br />

Raw UNIX Coverages<br />

PC ARCVIEW 1 Coverages<br />

Running <strong>the</strong> Plot Programs<br />

Installing ARCVIEW 1<br />

Using ARCVIEW 1<br />

ARCVIEW 1 Files<br />

ARCVIEW 3 Files<br />

Coverage Data Definition<br />

DLG Optional Format<br />

Descripton <strong>of</strong> Map Units<br />

TABLE OF CONTENTS

---

DISCLAIMER<br />

This Compact Disc-Read Only Memory (CD-ROM) publication was prepared<br />

by an agency <strong>of</strong> <strong>the</strong> United States Government. Nei<strong>the</strong>r <strong>the</strong> United States<br />

Government nor any agency <strong>the</strong>re<strong>of</strong>, nor any <strong>of</strong> <strong>the</strong>ir employees, makes any warranty,<br />

expressed or implied, or assumes any legal liability or responsibility for <strong>the</strong> accuracy,<br />

completeness, or usefulness <strong>of</strong> any information, apparatus, product, or process<br />

disclosed in this report, or represents that its use would not infringe privately owned<br />

rights. Reference <strong>the</strong>rein to any specific commercial product, process, or service by<br />

trade name, trademark, manufacturer, or o<strong>the</strong>rwise does not necessarily constitute or<br />

imply its endorsement, recommendation, or favoring by <strong>the</strong> United States<br />

Government or any agency <strong>the</strong>re<strong>of</strong>. Any views <strong>and</strong> opinions <strong>of</strong> authors expressed<br />

herein do not necessarily state or reflect those <strong>of</strong> <strong>the</strong> United States Government or any<br />

agency <strong>the</strong>re<strong>of</strong>.<br />

Although all data <strong>and</strong> s<strong>of</strong>tware published on this CD-ROM have been used by<br />

<strong>the</strong> <strong>USGS</strong>, no warranty, expressed or implied, is made by <strong>the</strong> U.S. Geological Survey<br />

as to <strong>the</strong> accuracy <strong>of</strong> <strong>the</strong> data <strong>and</strong> related materials <strong>and</strong>/or <strong>the</strong> functioning <strong>of</strong> <strong>the</strong><br />

s<strong>of</strong>tware. The act <strong>of</strong> distribution shall not constitute any such warranty, <strong>and</strong> no<br />

responsibility is assumed by <strong>the</strong> <strong>USGS</strong> in <strong>the</strong> use <strong>of</strong> <strong>the</strong>se data, s<strong>of</strong>tware, or related<br />

materials.<br />

Graphical map depictions on this disc are intended to be used within <strong>the</strong> map<br />

scale limits applicable to <strong>the</strong> source data. Although s<strong>of</strong>tware enables <strong>the</strong> user to show<br />

images on <strong>the</strong> disc at various scales, <strong>the</strong> user is cautioned to refer to <strong>the</strong> source<br />

documentation for <strong>the</strong> appropriate map scale limitations.

---

SYSTEM REQUIREMENTS<br />

This CD-ROM was produced in accordance with <strong>the</strong> ISO 9660 st<strong>and</strong>ard <strong>and</strong><br />

thus allows access to <strong>the</strong> disc files by computers with ISO 9660 s<strong>of</strong>tware drivers. The<br />

disc contains Adobe Acrobat Reader s<strong>of</strong>tware for DOS, Macintosh, UNIX, <strong>and</strong><br />

Windows. as well as a graphics display program, ArcView 1, for Windows 3.x.<br />

ARCVIEW 1 REQUIREMENTS<br />

80386 or better CPU<br />

Math coprocessor recommended<br />

Windows 3.0 or higher but not Windows 95<br />

4 Mb <strong>of</strong> RAM, 8 Mb strongly recommended<br />

15 Mb <strong>of</strong> disk space<br />

Super VGA graphics system, 256 colors, 640x480 pixels minimum,<br />

1024x768 pixels strongly recommended<br />

Micros<strong>of</strong>t-compatible mouse<br />

Windows-supported printer<br />

ARCVIEW 3 REQUIREMENTS<br />

or<br />

80486 or better CPU<br />

Windows 3.x, 95, or NT<br />

12-16 Mb <strong>of</strong> RAM<br />

Super VGA graphics system, 256 colors, 640x480 pixels minimum,<br />

1024x768 pixels strongly recommended<br />

Micros<strong>of</strong>t-compatible mouse<br />

Power Macintosh or 68040 processor with FPU<br />

System 7.1 or higher<br />

16-18 Mb <strong>of</strong> RAM

---

ADOBE ACROBAT READER REQUIREMENTS:<br />

A color display monitor is strongly recommended with all platforms.<br />

Windows 95 - rs32e30.exe<br />

Minimum<br />

i386(TM), i486(TM), Pentium(R), or<br />

Pentium Pro processor-based personal computer<br />

Micros<strong>of</strong>t Windows 95, or Windows NT(R) 3.51 or later<br />

8 MB <strong>of</strong> RAM (16 MB for Windows NT) for Acrobat Reader<br />

10 MB <strong>of</strong> available hard-disk space<br />

Recommended<br />

Pentium processor-based personal computer<br />

Windows 95 or Windows NT<br />

16 MB <strong>of</strong> RAM (24 for Windows NT)<br />

10 MB <strong>of</strong> available hard-disk space<br />

Windows NT - rs32e30.exe<br />

Minimum<br />

i386(TM), i486(TM), Pentium(R), or Pentium Pro processor<br />

Windows NT(R) 3.51 or later<br />

8 MB <strong>of</strong> RAM (16 MB for Windows NT) for Acrobat Reader<br />

10 MB <strong>of</strong> available hard-disk space<br />

Recommended<br />

Pentium processor-based personal<br />

computer<br />

Windows 95 or Windows NT<br />

16 MB <strong>of</strong> RAM (24 for Windows NT)<br />

10 MB <strong>of</strong> available hard-disk space

---

Windows 3.1 <strong>and</strong> 3.11 for Workgroups - rs16e30.exe<br />

Minimum<br />

i386(TM), i486(TM), Pentium(R), or Pentium Pro processor<br />

Micros<strong>of</strong>t Windows 3.1 or Windows 3.11 or later<br />

8 MB <strong>of</strong> RAM for Acrobat Reader<br />

5 MB <strong>of</strong> available hard-disk space<br />

Recommended<br />

Pentium processor-based personal computer<br />

Micros<strong>of</strong>t Windows 3.1 or Windows 3.11 or later<br />

12 MB <strong>of</strong> available hard-disk space<br />

Macintosh <strong>and</strong> Power Macintosh - Install Acrobat Reader 3.0, Search Installer<br />

Minimum<br />

Macintosh with a 68020 or greater processor, or Power Macintosh<br />

3.5 MB <strong>of</strong> RAM (5 MB for Power Macintosh) available to Acrobat Reader<br />

Apple(R) System S<strong>of</strong>tware version 7.1 or later<br />

Recommended<br />

8 MB <strong>of</strong> available RAM<br />

Apple System S<strong>of</strong>tware version 7.1.2 or later<br />

12.5 MB <strong>of</strong> available hard-disk space<br />

UNIX<br />

UNIX system requirements<br />

12 MB <strong>of</strong> disk space for Acrobat Reader<br />

System with 32 MB <strong>of</strong> RAM<br />

Sun SPARCstation(R) - acroread_sunos_30.tar.gz, acroread_solaris_30.tar.gz<br />

SunOS 4.1.3 or 4.1.4 or Solaris 2.3, 2.4, or 2.5<br />

OpenWindows(TM) (version 3.0 or later),<br />

Motif(TM) window manager (1.2.3 or later),<br />

OpenLook version 3.0, or<br />

Common Desktop Environment (CDE) 1.0 <strong>and</strong> above<br />

HP Series 9000 workstation, model 700 or greater - acroread_hpux_30.tar.gz<br />

HP-UX 9.0.3 or later<br />

X Window System(TM) X11R5 with HP-VUE or CDE 1.0<br />

12 megabytes <strong>of</strong> available hard disk space<br />

A 32 megabyte machine

---

IBM(R) RS/6000(TM) workstation - acroread_aix_30.tar.gz<br />

AIX 4.1 or later operating system<br />

Common Desktop Environment (CDE) or <strong>the</strong> Motif window manager<br />

Silicon Graphics workstation - acroread_irix_30.tar.gz<br />

IRIX(TM) 5.3 or later operating system s<strong>of</strong>tware<br />

12 megabytes <strong>of</strong> available hard disk space<br />

A 32 megabyte machine<br />

Linux workstation - acroread_linux_30.tar.gz<br />

LINUX 5.3 or later operating system s<strong>of</strong>tware<br />

12 megabytes <strong>of</strong> available hard disk space<br />

A 32 megabyte machine<br />

OS/2 - aro2e30.exe<br />

Minimum<br />

i386, i486, Pentium, or Pentium Pro processor<br />

IBM OS/2 Warp or Warp Connect 3.0 or later<br />

4 MB application RAM available to Acrobat Reader<br />

8 MB RAM for system<br />

5 MB hard-disk space, plus 5 MB temporary space for installation<br />

Recommended<br />

Pentium processor<br />

IBM OS/2 Warp 4.0<br />

Adobe Acrobat Reader 1.0 for DOS - rdrdos10.zip<br />

Minimum<br />

i386(TM), i486(TM) processor<br />

Micros<strong>of</strong>t DOS 3.3 or later<br />

2 MB <strong>of</strong> RAM for Acrobat Reader.<br />

5 MB <strong>of</strong> available hard-disk space<br />

Recommended<br />

486 or Pentium processor<br />

Micros<strong>of</strong>t DOS 3.3 or later<br />

4 MB <strong>of</strong> application RAM<br />

5 MB <strong>of</strong> available hard-disk space

---

ACKNOWLEDGEMENTS<br />

Development <strong>of</strong> <strong>the</strong> graphics files on this CD-ROM spanned many years <strong>and</strong><br />

involved <strong>the</strong> efforts <strong>of</strong> many organizations <strong>and</strong> individuals. Most <strong>of</strong> <strong>the</strong> digitizing<br />

was done in GSMAP by Jeff Wynn (<strong>USGS</strong>) <strong>and</strong> o<strong>the</strong>rs. The nor<strong>the</strong>rn quadrangles<br />

were scanned from tracings created by <strong>the</strong> geologists. Thanks to <strong>the</strong> following<br />

authors for those materials:<br />

John H. Stewart (<strong>USGS</strong>)<br />

Dennis P. Cox (<strong>USGS</strong>)<br />

Floyd Gray (<strong>USGS</strong>)<br />

W. E. Brooks (<strong>USGS</strong>)<br />

Thanks to Corporación Venezolana de Guayana, Técnica Minera C.A. <strong>and</strong> <strong>the</strong><br />

following authors <strong>of</strong> Venezuela maps <strong>and</strong> reports for <strong>the</strong>ir help in <strong>the</strong> preparation <strong>of</strong><br />

<strong>the</strong> digital files:<br />

Juan Acosta<br />

Jesús Arespón<br />

Yasmin Estanga<br />

Luis Franco<br />

Andrés García<br />

Yol<strong>and</strong>a Lopez<br />

Elis Lugo<br />

Iris Marcano<br />

Félix Martínez<br />

Vicente Mendoza-S.<br />

Stephen D. Olmore<br />

Inés Rendón<br />

Haydée Rincón<br />

Nelson Rivero<br />

Edixon Salazar<br />

Gary B. Sidder (formerly <strong>USGS</strong>, now Golden Star <strong>Resource</strong>s)<br />

Frank Tovar<br />

Thanks to David K. Traudt, <strong>USGS</strong>, who assembled <strong>the</strong> files <strong>and</strong> directories<br />

from tape to master CD-ROM. Thanks to <strong>the</strong> following personnel in <strong>the</strong> <strong>USGS</strong> who<br />

provided disk files <strong>of</strong> Bulletin 2062 text <strong>and</strong> figures as well as many thoughtful<br />

suggestions for improvements to <strong>the</strong> maps <strong>and</strong> text on <strong>the</strong> CD-ROM.<br />

Frederick C. Brunstein<br />

David A. Emery<br />

Will Stettner<br />

Judith W. Stoeser

---

CONTACTS<br />

Questions about <strong>the</strong> digital map files should be directed to:<br />

Paul Schruben Telephone (703) 648-6142<br />

FAX (703) 648-6383<br />

E-mail pschrube@usgs.gov<br />

U.S. Geological Survey, 954 National Center, Reston, VA 22092-9998.<br />

Technical help with ArcView 1 is available via CompuServe by typing GO ESRI.<br />

Copies <strong>of</strong> <strong>the</strong> original <strong>USGS</strong> 1993 Bulletin 2062, MF maps cited in <strong>the</strong> Documentation<br />

<strong>of</strong> Map Units, <strong>and</strong> this CD-ROM are available from:<br />

U.S. Geological Survey, Map Distribution<br />

Box 25286, Building 810<br />

Federal Center<br />

Denver, CO 80225<br />

Tel: (888) ASK-<strong>USGS</strong> or for overseas access<br />

(703) 648-6045.

---

DISC CONTENTS<br />

1readme.doc description <strong>of</strong> this disc, Micros<strong>of</strong>t Word 6 file<br />

1readme.mac.text description <strong>of</strong> this disc, Macintosh/OS plain text file<br />

1readme.pdf description <strong>of</strong> this disc, Adobe Acrobat Reader file<br />

1readmet.dos description <strong>of</strong> this disc, MS/DOS plain text file<br />

1readmew.dos description <strong>of</strong> this disc, Micros<strong>of</strong>t Word for Windows 1.0<br />

acrobat directory containing Acrobat Reader installer programs<br />

arcview1 directory containing ArcView 1 installer program<br />

arcpc directory containing PC ArcView 1 <strong>and</strong> ARC/INFO directories.<br />

Same as arcunix6 directory below<br />

arcunix6 directory containing ArcView 1 <strong>and</strong> ARC/INFO 6.1.2 directories<br />

at directory containing files for Atabapo 2°x3° quadrangle<br />

(Venezuela part)<br />

at.aml ARC/PLOT program for 44" Versatec plotter<br />

at.av ArcView 1 file<br />

at.gra ARC/PLOT plot file for 44" Versatec plotter<br />

atanno5 geographic place name annotation<br />

atcor correlation <strong>of</strong> map units<br />

atft faults<br />

atge geology<br />

atlab rock unit label annotation<br />

atleg map legend<br />

atma buried magnetic bodies<br />

atout quadrangle outline <strong>and</strong> lat/long numbers<br />

atpl political boundaries<br />

atscale 1:500,000 scale bar, title, & citation<br />

atst single-line tributaries<br />

attc latitude/longitude tics for this quadrangle<br />

grid lat/long grid lines for index map<br />

index index map showing quadrangle names <strong>and</strong> surrounding<br />

countries<br />

vztc latitude/longitude numbers <strong>and</strong> tics for index map<br />

ay directory containing Puerto Ayacucho 2°x3° quadrangle<br />

(Venezuela part) files<br />

ay.aml ARC/PLOT program for 44" Versatec plotter<br />

ay.av ArcView 1 file<br />

ay.gra ARC/PLOT plot file for 44" Versatec plotter<br />

ayanno5 geographic place name annotation<br />

aycor correlation <strong>of</strong> map units<br />

aycrlbm crossection geology rock unit labels<br />

aycrm crossection geology polygons<br />

ayft faults<br />

ayge geology<br />

aylab rock unit label annotation<br />

aylabcr crossection line <strong>and</strong> annotation on map<br />

ayleg map legend<br />

aylegpt map legend points<br />

ayma buried magnetic bodies<br />

aymalab buried magnetic bodies<br />

ayout quadrangle outline <strong>and</strong> lat/long numbers<br />

aypl political boundaries<br />

ayrd roads

---

ayscale 1:500,000 scale bar, title, & citation<br />

ayst single-line tributaries<br />

aytc latitude/longitude tics for this quadrangle<br />

grid lat/long grid lines for index map<br />

index index map showing quadrangle names <strong>and</strong> surrounding<br />

countries<br />

vztc latitude/longitude numbers <strong>and</strong> tics for index map<br />

ca directory containing Río Caura 2° by 3° quadrangle files<br />

ca.aml ARC/PLOT program for 44" Versatec plotter<br />

ca.av ArcView 1 file<br />

ca.gra ARC/PLOT plot file for 44" Versatec plotter<br />

caanno5 geographic place name annotation<br />

cacor correlation <strong>of</strong> map units<br />

caft faults<br />

cage geology<br />

calab rock unit label annotation<br />

caleg map legend<br />

calegpt map legend points<br />

cama buried magnetic bodies<br />

caout quadrangle outline <strong>and</strong> lat/long numbers<br />

capl political boundaries<br />

cascale 1:500,000 scale bar, title, & citation<br />

cast single-line tributaries<br />

catc latitude/longitude tics for this quadrangle<br />

grid lat/long grid lines for index map<br />

index index map showing quadrangle names <strong>and</strong> surrounding<br />

countries<br />

vztc latitude/longitude numbers <strong>and</strong> tics for index map<br />

es directory containing La Esmeralda 2°x3° quadrangle<br />

(Venezuela part) files<br />

es.aml ARC/PLOT program for 44" Versatec plotter<br />

es.av ArcView 1 file<br />

es.gra ARC/PLOT plot file for 44" Versatec plotter<br />

esanno5 geographic place name annotation<br />

escor correlation <strong>of</strong> map units<br />

esft faults<br />

esge geology<br />

eslab rock unit label annotation<br />

esleg map legend<br />

eslegpt map legend points<br />

esma buried magnetic bodies<br />

esout quadrangle outline <strong>and</strong> lat/long numbers<br />

espl political boundaries<br />

esscale 1:500,000 scale bar, title, & citation<br />

esst single-line tributaries<br />

estc latitude/longitude tics for this quadrangle<br />

grid lat/long grid lines for index map<br />

index index map showing quadrangle names <strong>and</strong> surrounding<br />

countries<br />

vztc latitude/longitude numbers <strong>and</strong> tics for index map<br />

gu directory containing Guri <strong>and</strong> sou<strong>the</strong>rn part <strong>of</strong> <strong>the</strong> Tucupita<br />

2°x3° quadrangles files<br />

grid lat/long grid lines for index map<br />

gu.aml ARC/PLOT program for 44" Versatec plotter

---

gu.av ArcView 1 file<br />

gu.gra ARC/PLOT plot file for 44" Versatec plotter<br />

guanno5 geographic place name annotation<br />

gucor correlation <strong>of</strong> map units<br />

guft faults<br />

guge geology<br />

gulab rock unit label annotation<br />

guleg map legend<br />

gulegpt map legend points<br />

guout quadrangle outline <strong>and</strong> lat/long numbers<br />

gupl political boundaries<br />

gurd roads<br />

guscale 1:500,000 scale bar, title, & citation<br />

gust single-line tributaries<br />

gutc latitude/longitude tics for this quadrangle<br />

index index map showing quadrangle names <strong>and</strong> surrounding<br />

countries<br />

vztc latitude/longitude numbers <strong>and</strong> tics for index map<br />

ma directory containing Río Mavaca 2°x3° quadrangle (Venezuela<br />

part)<br />

grid lat/long grid lines for index map<br />

index index map showing quadrangle names <strong>and</strong> surrounding<br />

countries<br />

ma.aml ARC/PLOT program for 44" Versatec plotter<br />

ma.av ArcView 1 file<br />

ma.gra ARC/PLOT plot file for 44" Versatec plotter<br />

maanno5 geographic place name annotation<br />

macor correlation <strong>of</strong> map units<br />

maft faults<br />

mage geology<br />

malab rock unit label annotation<br />

maleg map legend<br />

mama buried magnetic bodies<br />

maout quadrangle outline <strong>and</strong> lat/long numbers<br />

mascale 1:500,000 scale bar, title, & citation<br />

mast single-line tributaries<br />

matc latitude/longitude tics for this quadrangle<br />

vztc latitude/longitude numbers <strong>and</strong> tics for index map<br />

pc directory containing Piedra de Cocuy 2°x3° quadrangle<br />

(Venezuela part) files<br />

grid lat/long grid lines for index map<br />

index index map showing quadrangle names <strong>and</strong> surrounding<br />

countries<br />

pc.aml ARC/PLOT program for 44" Versatec plotter<br />

pc.av ArcView 1 file<br />

pc.gra ARC/PLOT plot file for 44" Versatec plotter<br />

pcanno5 geographic place name annotation<br />

pccor correlation <strong>of</strong> map units<br />

pcft faults<br />

pcge geology<br />

pclab rock unit label annotation<br />

pcleg map legend<br />

pclegpt map legend points<br />

pcma buried magnetic bodies

---

pcout quadrangle outline <strong>and</strong> lat/long numbers<br />

pcpl political boundaries<br />

pcscale 1:500,000 scale bar, title, & citation<br />

pcst single-line tributaries<br />

pctc latitude/longitude tics for this quadrangle<br />

vztc latitude/longitude numbers <strong>and</strong> tics for index map<br />

pi directory containing Ciudad Piar <strong>and</strong> part <strong>of</strong> <strong>the</strong> Ciudad<br />

Bolivar 2°x3° quadrangles files<br />

fnt040 ARC/INFO font file necessary for sag fault line symbol<br />

grid lat/long grid lines for index map<br />

index index map showing quadrangle names <strong>and</strong> surrounding<br />

countries<br />

pi.aml ARC/PLOT program for 44" Versatec plotter<br />

pi.av ArcView 1 file<br />

pi.gra ARC/PLOT plot file for 44" Versatec plotter<br />

pianno5 geographic place name annotation<br />

picor correlation <strong>of</strong> map units<br />

pift faults<br />

pige geology<br />

pilab rock unit label annotation<br />

pileg map legend<br />

pilegpt map legend points<br />

pima kimberlite area<br />

piout quadrangle outline <strong>and</strong> lat/long numbers<br />

pipl political boundaries<br />

pird roads<br />

piscale 1:500,000 scale bar, title, & citation<br />

pisr structural lines from SLAR<br />

pist single-line tributaries<br />

pitc latitude/longitude tics for this quadrangle<br />

vztc latitude/longitude numbers <strong>and</strong> tics for index map<br />

se directory containing Santa Elena 2°x3° quadrangle (Venezuela<br />

part) files<br />

grid lat/long grid lines for index map<br />

index index map showing quadrangle names <strong>and</strong> surrounding<br />

countries<br />

se.aml ARC/PLOT program for 44" Versatec plotter<br />

se.av ArcView 1 file<br />

se.gra ARC/PLOT plot file for 44" Versatec plotter<br />

seanno5 geographic place name annotation<br />

secor correlation <strong>of</strong> map units<br />

seft faults<br />

sege geology<br />

selab rock unit label annotation<br />

seleg map legend<br />

selegpt map legend points<br />

seout quadrangle outline <strong>and</strong> lat/long numbers<br />

sepl political boundaries<br />

serd roads<br />

sescale 1:500,000 scale bar, title, & citation<br />

sest single-line tributaries<br />

setc latitude/longitude tics for this quadrangle<br />

vztc latitude/longitude numbers <strong>and</strong> tics for index map<br />

sf directory containing San Fern<strong>and</strong>o de Apure 2°x3° quadrangle

---

(Bolivar part) files<br />

grid lat/long grid lines for index map<br />

index index map showing quadrangle names <strong>and</strong> surrounding<br />

countries<br />

sf.aml ARC/PLOT program for 44" Versatec plotter<br />

sf.av ArcView 1 file<br />

sf.gra ARC/PLOT plot file for 44" Versatec plotter<br />

sfanno5 geographic place name annotation<br />

sfcor correlation <strong>of</strong> map units<br />

sfft faults<br />

sfge geology<br />

sflab rock unit label annotation<br />

sfleg map legend<br />

sflegpt map legend points<br />

sfout quadrangle outline <strong>and</strong> lat/long numbers for ArcView<br />

sfpl political boundaries<br />

sfscale 1:500,000 scale bar, title, & citation<br />

sfst single-line tributaries<br />

sftc latitude/longitude tics for this quadrangle<br />

vztc latitude/longitude numbers <strong>and</strong> tics for index map<br />

vz directory containing combined map coverages for <strong>Venezuelan</strong><br />

Guayana Shield, all quadrangles<br />

av.mrk ArcView markerset to be copied to <strong>the</strong> ARCHOME directory<br />

av.txt ArcView textset to be copied to <strong>the</strong> ARCHOME directory<br />

deposit mineral deposits, prospects <strong>and</strong> occurrences<br />

equi2geo.prj projection file for converting equidistant conic to<br />

decimal degrees<br />

fnt040 ARC/INFO font file necessary for sag fault line symbol<br />

ge.ai Illustrator 6.0 version <strong>of</strong> ge.eps<br />

ge.eps ARC/PLOT Postscript plot file for 44" Versatec plotter<br />

ge.gra ARC/PLOT plot file for 44" Versatec plotter<br />

geo2equi.prj projection file for converting decimal degrees to<br />

equidistant conic<br />

grid lat/long grid lines for index map<br />

index index map showing quadrangle names <strong>and</strong> surrounding<br />

countries<br />

mrdsek.mrk ARC/PLOT markerset for o<strong>the</strong>r point symbols<br />

myalcgeol.mrk ARC/PLOT markerset for cities, bedding, joint symbols<br />

myplotter.shd ARC/PLOT shadeset for geology patterns<br />

myplt.lin ARC/PLOT lineset for faults, roads, political boundaries<br />

places geographic place names<br />

ra mineral resource permissive areas map A<br />

raanno mineral resource permissive areas map A annotation<br />

rb mineral resource permissive areas map B<br />

rbanno mineral resource permissive areas map B annotation<br />

rbstruct mineral resource permissive areas map B structural<br />

features<br />

scale scalebar <strong>and</strong> projection information<br />

vz.aml ARC/PLOT program for 44" Versatec plotter<br />

vz.av ArcView 1 view file<br />

vz.apr ArcView 3 project file<br />

vzcor correlation <strong>of</strong> map units<br />

vzctry Nor<strong>the</strong>ast South America country borders<br />

vzft faults, annotation, joints, <strong>and</strong> bedding

---

vzge geology<br />

vzlab rock unit annotation <strong>and</strong> leaders<br />

vzma buried magnetic bodies<br />

vzout outer edge <strong>of</strong> combined quadrangles in study area<br />

vzpl study area political boundaries<br />

vzprov Venezuela province boundaries for index map<br />

vzrd roads<br />

vzst single-line tributaries <strong>and</strong> annotation<br />

vztc latitude/longitude numbers <strong>and</strong> tics for index map<br />

arcunix7 directory containing ArcView 3 <strong>and</strong> ARC/INFO 7 directory<br />

vz directory containing combined map coverages for <strong>Venezuelan</strong><br />

Guayana Shield, all quadrangles. Same as in<br />

arcunix6/vz.<br />

bull2062 directory containing text <strong>and</strong> figures from Bulletin 2062<br />

doc<br />

tables.doc Word 5.1 tables 1-2, 4-11<br />

tabside.doc Word 5.1 table 3<br />

mif<br />

b2062con.mif framemaker 3.0p1b table <strong>of</strong> contents<br />

b2062fnt.mif framemaker 3.0p1b cover 1, cover 2, i, ii, iii<br />

b2062txt.mif framemaker 3.0p1b main body, p. 1-120<br />

rtf<br />

b2062con.rtf rich text (RTF) table <strong>of</strong> contents<br />

b2062txt.rtf rich text (RTF) main body, p. 3-5<br />

tif<br />

vzget.tif TIF Plate 2, geology, key part<br />

vzge.tif TIF Plate 2, geologic map part<br />

vzmin.tif TIF Plate 6, mineral deposits<br />

txt<br />

b2062con.txt text table <strong>of</strong> contents<br />

b2062fnt.txt text i, ii<br />

b2062txt.txt text main body, p. 1-72<br />

dlg directory containing Digital Line Graph (DLG) Optional files<br />

cor.dlg correlation <strong>of</strong> map units in Equidistant Conic projection<br />

cordd.dlg correlation <strong>of</strong> map units in decimal degrees<br />

ft.dlg faults in Equidistant Conic projection<br />

ftdd.dlg faults in decimal degrees<br />

ge.dlg geology in Equidistant Conic projection<br />

gedd.dlg geology in decimal degrees<br />

ptype.unl rock unit names, descriptions, colors for Versatec<br />

plotter<br />

scale.dlg scale bar in Equidistant Conic projection<br />

scaledd.dlg scale bar in decimal degrees<br />

vzline.unl fault <strong>and</strong> contact line types<br />

export directory containing directories <strong>of</strong> ARC/INFO export files <strong>and</strong><br />

programs<br />

at directory containing Atabapo quadrangle files<br />

at.aml ARC/PLOT program for 44" Versatec plotter<br />

at.av ArcView 1 file<br />

at.gra ARC/PLOT 1040 plot file for 44" Versatec plotter.<br />

This a binary file<br />

atanno5.e00 geographic place name annotation<br />

atcor.e00 correlation <strong>of</strong> map units<br />

atft.e00 faults

---

atge.e00 geology<br />

atlab.e00 rock unit label annotation<br />

atleg.e00 map legend<br />

atma.e00 buried magnetic bodies<br />

atout.e00 quadrangle outline <strong>and</strong> lat/long numbers<br />

atpl.e00 political boundaries<br />

atscale.e00 1:500,000 scale bar, title, & citation<br />

atst.e00 single-line tributaries<br />

attc.e00 latitude longitude tics for this quadrangle<br />

grid.e00 lat/long grid lines for index map<br />

import.aml ARC program for importing coverage<br />

index.e0* index map showing quadrangle names <strong>and</strong> surrounding<br />

countries, files 0-1<br />

vztc.e00 latitude longitude tics for index map<br />

ay directory containing Puerto Ayacucho quadrangle files<br />

ay.aml ARC/PLOT program for 44" Versatec plotter<br />

ay.av ArcView 1 file<br />

ay.gra ARC/PLOT 1040 plot file for 44" Versatec plotter.<br />

This a binary file<br />

ayanno5.e00 geographic place name annotation<br />

aycor.e00 correlation <strong>of</strong> map units<br />

aycrlbm.e00 cross section labels<br />

aycrm.e00 cross section arcs<br />

ayft.e00 faults<br />

ayge.e00 geology<br />

aylab.e00 rock unit label annotation<br />

aylabcr.e00 rock unit label annotation for cross section<br />

ayleg.e00 map legend<br />

aylegpt.e00 map legend points<br />

ayma.e00 buried magnetic bodies<br />

aymalab.e00 buried magnetic bodies labels<br />

ayout.e00 quadrangle outline <strong>and</strong> lat/long numbers<br />

aypl.e00 political boundaries<br />

ayrd.e00 roads<br />

ayscale.e00 1:500,000 scale bar, title, & citation<br />

ayst.e00 single-line tributaries<br />

aytc.e00 latitude longitude tics for this quadrangle<br />

grid.e00 lat/long grid lines for index map<br />

import.aml ARC program for importing coverage<br />

index.e0* index map showing quadrangle names <strong>and</strong> surrounding<br />

countries, files 0-1<br />

vztc.e00 latitude longitude tics for index map<br />

ca directory containing Río Caura quadrangle files<br />

ca.aml ARC/PLOT program for 44" Versatec plotter<br />

ca.av ArcView 1 file<br />

ca.gra ARC/PLOT 1040 plot file for 44" Versatec plotter.<br />

This a binary file<br />

caanno5.e00 geographic place name annotation<br />

cacor.e00 correlation <strong>of</strong> map units<br />

caft.e00 faults<br />

cage.e00 geology<br />

calab.e00 rock unit label annotation<br />

caleg.e00 map legend<br />

calegpt.e00 map legend points

---

cama.e00 buried magnetic bodies<br />

caout.e00 quadrangle outline <strong>and</strong> lat/long numbers<br />

capl.e00 political boundaries<br />

cascale.e00 1:500,000 scale bar, title, & citation<br />

cast.e00 single-line tributaries<br />

catc.e00 latitude longitude tics for this quadrangle<br />

grid.e00 lat/long grid lines for index map<br />

import.aml ARC program for importing coverage<br />

index.e0* index map showing quadrangle names <strong>and</strong> surrounding<br />

countries, files 0-1<br />

vztc.e00 latitude longitude tics for index map<br />

es directory containing La Esmeralda quadrangle files<br />

es.aml ARC/PLOT program for 44" Versatec plotter<br />

es.av ArcView 1 file<br />

es.gra ARC/PLOT 1040 plot file for 44" Versatec plotter.<br />

This a binary file<br />

esanno5.e00 geographic place name annotation<br />

escor.e00 correlation <strong>of</strong> map units<br />

esft.e00 faults<br />

esge.e00 geology<br />

eslab.e00 rock unit label annotation<br />

esleg.e00 map legend<br />

eslegpt.e00 map legend points<br />

esma.e00 buried magnetic bodies<br />

esout.e00 quadrangle outline <strong>and</strong> lat/long numbers<br />

espl.e00 political boundaries<br />

esscale.e00 1:500,000 scale bar, title, & citation<br />

esst.e00 single-line tributaries<br />

estc.e00 latitude longitude tics for this quadrangle<br />

grid.e00 lat/long grid lines for index map<br />

import.aml ARC program for importing coverage<br />

index.e0* index map showing quadrangle names <strong>and</strong> surrounding<br />

countries, files 0-1<br />

vztc.e00 latitude longitude tics for index map<br />

gu directory containing Guri <strong>and</strong> Tucupita quadrangle files<br />

grid.e00 lat/long grid lines for index map<br />

gu.aml ARC/PLOT program for 44" Versatec plotter<br />

gu.av ArcView 1 file<br />

gu.gra ARC/PLOT 1040 plot file for 44" Versatec plotter.<br />

This a binary file<br />

guanno5.e00 geographic place name annotation<br />

gucor.e00 correlation <strong>of</strong> map units<br />

guft.e00 faults<br />

guge.e0* geology files, 0-2<br />

gulab.e00 rock unit label annotation<br />

guleg.e00 map legend<br />

gulegpt.e00 map legend points<br />

guout.e00 quadrangle outline <strong>and</strong> lat/long numbers<br />

gupl.e00 political boundaries<br />

gurd.e00 roads<br />

guscale.e00 1:500,000 scale bar, title, & citation<br />

gust.e00 single-line tributaries<br />

gutc.e00 latitude longitude tics for this quadrangle<br />

import.aml ARC program for importing coverage

---

index.e0* index map showing quadrangle names <strong>and</strong> surrounding<br />

countries, files 0-1<br />

vztc.e00 latitude longitude tics for index map<br />

ma directory containing Río Mavaca quadrangle files<br />

grid.e00 lat/long grid lines for index map<br />

import.aml ARC program for importing coverage<br />

index.e0* index map showing quadrangle names <strong>and</strong> surrounding<br />

countries, files 0-1<br />

ma.aml ARC/PLOT program for 44" Versatec plotter<br />

ma.av ArcView 1 file<br />

ma.gra ARC/PLOT 1040 plot file for 44" Versatec plotter.<br />

This a binary file<br />

maanno5.e00 geographic place name annotation<br />

macor.e00 correlation <strong>of</strong> map units<br />

maft.e00 faults<br />

mage.e00 geology<br />

malab.e00 rock unit label annotation<br />

maleg.e00 map legend<br />

mama.e00 buried magnetic bodies<br />

maout.e00 quadrangle outline <strong>and</strong> lat/long numbers<br />

mascale.e00 1:500,000 scale bar, title, & citation<br />

mast.e00 single-line tributaries<br />

matc.e00 latitude longitude tics for this quadrangle<br />

vztc.e00 latitude longitude tics for index map<br />

pc directory containing Piedra de Cocuy quadrangle files<br />

grid.e00 lat/long grid lines for index map<br />

import.aml ARC program for importing coverage<br />

index.e0* index map showing quadrangle names <strong>and</strong> surrounding<br />

countries, files 0-1<br />

pc.aml ARC/PLOT program for 44" Versatec plotter<br />

pc.av ArcView 1 file<br />

pc.gra ARC/PLOT 1040 plot file for 44" Versatec plotter.<br />

This a binary file<br />

pcanno5.e00 geographic place name annotation<br />

pccor.e00 correlation <strong>of</strong> map units<br />

pcft.e00 faults<br />

pcge.e00 geology<br />

pclab.e00 rock unit label annotation<br />

pcleg.e00 map legend<br />

pclegpt.e00 map legend points<br />

pcma.e00 buried magnetic bodies<br />

pcout.e00 quadrangle outline <strong>and</strong> lat/long numbers<br />

pcpl.e00 political boundaries<br />

pcscale.e00 1:500,000 scale bar, title, & citation<br />

pcst.e00 single-line tributaries<br />

pctc.e00 latitude longitude tics for this quadrangle<br />

vztc.e00 latitude longitude tics for index map<br />

pi directory containing Ciudad Piar <strong>and</strong> Ciudad Bolivar<br />

quadrangle files<br />

fnt040 ARC/INFO font file necessary for sag fault line symbol<br />

grid.e00 lat/long grid lines for index map<br />

import.aml ARC program for importing coverage<br />

index.e0* index map showing quadrangle names <strong>and</strong> surrounding<br />

countries, files 0-1

---

pi.aml ARC/PLOT program for 44" Versatec plotter<br />

pi.av ArcView 1 file<br />

pi.gra ARC/PLOT 1040 plot file for 44" Versatec plotter.<br />

This a binary file.<br />

pianno5.e00 geographic place name annotation<br />

picor.e00 correlation <strong>of</strong> map units<br />

pift.e00 faults<br />

pige.e0* geology, 0-2<br />

pilab.e00 rock unit label annotation<br />

pileg.e00 map legend<br />

pilegpt.e00 map legend points<br />

pima.e00 buried magnetic bodies<br />

piout.e00 quadrangle outline <strong>and</strong> lat/long numbers<br />

pipl.e00 political boundaries<br />

pird.e00 roads<br />

piscale.e00 1:500,000 scale bar, title, & citation<br />

pisr.e00 structural lines from SLAR<br />

pist.e00 single-line tributaries<br />

pitc.e00 latitude longitude tics for this quadrangle<br />

vztc.e00 latitude longitude tics for index map<br />

se directory containing Santa Elena quadrangle files<br />

grid.e00 lat/long grid lines for index map<br />

import.aml ARC program for importing coverage<br />

index.e0* index map showing quadrangle names <strong>and</strong> surrounding<br />

countries, files 0-1<br />

se.aml ARC/PLOT program for 44" Versatec plotter<br />

se.av ArcView 1 file<br />

se.gra ARC/PLOT 1040 plot file for 44" Versatec plotter.<br />

This a binary file<br />

seanno5.e00 geographic place name annotation<br />

secor.e00 correlation <strong>of</strong> map units<br />

seft.e00 faults<br />

sege.e0* geology, 0-1<br />

selab.e00 rock unit label annotation<br />

seleg.e00 map legend<br />

selegpt.e00 map legend points<br />

seout.e00 quadrangle outline <strong>and</strong> lat/long numbers<br />

sepl.e00 political boundaries<br />

serd.e00 roads<br />

sescale.e00 1:500,000 scale bar, title, & citation<br />

sest.e00 single-line tributaries<br />

setc.e00 latitude longitude tics for this quadrangle<br />

vztc.e00 latitude longitude tics for index map<br />

sf directory containing San Fern<strong>and</strong>o quadrangle files<br />

grid.e00 lat/long grid lines for index map<br />

import.aml ARC program for importing coverage<br />

index.e0* index map showing quadrangle names <strong>and</strong> surrounding<br />

countries, files 0-1<br />

sf.aml ARC/PLOT program for 44" Versatec plotter<br />

sf.av ArcView 1 file<br />

sf.gra ARC/PLOT 1040 plot file for 44" Versatec plotter.<br />

This a binary file<br />

sfanno5.e00 geographic place name annotation<br />

sfcor.e00 correlation <strong>of</strong> map units

---

sfft.e00 faults<br />

sfge.e00 geology<br />

sflab.e00 rock unit label annotation<br />

sfleg.e00 map legend<br />

sflegpt.e00 map legend points<br />

sfout.e00 quadrangle outline <strong>and</strong> lat/long numbers<br />

sfpl.e00 political boundaries<br />

sfscale.e00 1:500,000 scale bar, title, & citation<br />

sfst.e00 single-line tributaries<br />

sftc.e00 latitude longitude tics for this quadrangle<br />

vztc.e00 latitude longitude tics for index map<br />

vz directory containing export files for combined coverages<br />

avmrk.e00 ArcView markerset to be copied to <strong>the</strong> ARC HOME directory<br />

avtxt.e00 ArcView textset to be copied to <strong>the</strong> ARC HOME directory<br />

deposit.e0* mineral deposits, prospects <strong>and</strong> occurrences, files 0-2<br />

equi2geo.prj projection file for converting equidistant conic to<br />

decimal degrees<br />

fnt040 ARC/INFO font file necessary for sag fault line symbol<br />

ge.gra ARC/PLOT 1040 plot file for 44" Versatec plotter.<br />

This a binary file<br />

geo2equi.prj projection file for converting decimal degrees to<br />

equidistant conic<br />

grid.e00 lat/long grid lines for index map<br />

import.aml ARC script for importing all coverages<br />

index.e0* index map showing quadrangle names <strong>and</strong> surrounding<br />

countries, files 0-1<br />

mrdsek.e00 ARC/PLOT markerset for o<strong>the</strong>r point symbols<br />

myalcgeol.e00 ARC/PLOT markerset for cities, bedding, joint symbols<br />

myplotter.e00 ARC/PLOT shadeset for geology patterns<br />

myplt.e00 ARC/PLOT lineset for faults, roads, political boundaries<br />

places.e00 geographic place names<br />

ptpat.e00 geology polygon lookup table, plotter patterns<br />

ptpl.e00 point symbol lookup table<br />

ptype.e00 geology polygon lookup table, Versatec colors<br />

ra.e0* mineral resource permissive areas map A<br />

raanno.e00 mineral resource permissive areas map A annotation<br />

rb.e0* mineral resource permissive areas map B files, 0-1<br />

rbanno.e00 mineral resource permissive areas map B annotation<br />

rbstruct.e00 mineral resource permissive areas map B structural<br />

features<br />

scale.e00 scalebar <strong>and</strong> projection information<br />

vz.aml ARC/PLOT program for 44" Versatec plotter<br />

vz.av ArcView 1 view file<br />

vz.apr ArcView 3 project file<br />

vzcor.e00 correlation <strong>of</strong> map units<br />

vzctry.e0* Nor<strong>the</strong>ast South America country borders, 0-1<br />

vzft.e00 faults, annotation, joints <strong>and</strong> bedding<br />

vzge.e00 geology files, 0-9<br />

vzlab.e0* rock unit annotation <strong>and</strong> leaders files, 0-2<br />

vzline.e00 lineset for Arc/Edit, Arc/Plot, Versatec plots<br />

vzma.e00 buried magnetic bodies<br />

vzout.e00 outer edge <strong>of</strong> combined quadrangles in study area<br />

vzpl.e00 study area political boundaries<br />

vzprov.e00 Venezuela province boundaries for index map

---

vzrd.e00 roads<br />

vzst.e0* single-line tributaries <strong>and</strong> annotation files, 0-2<br />

vztc.e00 latitude/longitude numbers <strong>and</strong> tics for index map

---

PROJECT OVERVIEW<br />

Conversion <strong>of</strong> <strong>the</strong> Venezuela maps to a computerized digital format was<br />

undertaken for <strong>the</strong> following reasons:<br />

1) The digital format facilitates <strong>the</strong> presentation <strong>and</strong> analysis <strong>of</strong> earth-science data.<br />

Digital maps can be displayed at any scale or projection, whereas a paper map has a<br />

fixed scale <strong>and</strong> projection. However, <strong>the</strong> maps on this disc are not intended to be used<br />

at any scale more detailed than 1:500,000.<br />

A geographic information system (GIS) allows combining <strong>and</strong> overlaying <strong>of</strong><br />

layers for analysis <strong>of</strong> spatial relations not readily apparent in <strong>the</strong> st<strong>and</strong>ard paper<br />

publication. Digital data on geology, geophysics, <strong>and</strong> geochemistry can be combined<br />

to create useful derivative products.<br />

2) The digital format was used to facilitate publication in both paper <strong>and</strong> electronic<br />

form. For <strong>the</strong> Río Caura paper map publication (Brooks <strong>and</strong> o<strong>the</strong>rs, 1995), digital<br />

images were sent to <strong>the</strong> Gerber plotter, a vector-to-film processor. The o<strong>the</strong>r<br />

1:500,000-scale MF maps were reproduced photographically from electrostatic plotter<br />

output on clear mylar. The published digital formats include this CD-ROM <strong>and</strong><br />

ARC/INFO Export files to be located on <strong>the</strong> World Wide Web on <strong>the</strong> Internet.

---

HISTORY OF THE MAPS<br />

The data in this CD-ROM are based on a mineral resource assessment <strong>of</strong> <strong>the</strong><br />

<strong>Venezuelan</strong> Guayana Shield, conducted between 1987 <strong>and</strong> 1991 by <strong>the</strong> U.S. Geological<br />

Survey <strong>and</strong> Corporación Venezolana de Guayana, Técnica Minera, (<strong>USGS</strong>, 1993). The<br />

<strong>Venezuelan</strong> Shield occupies about 415,000 sq km in <strong>the</strong> south <strong>and</strong> east part <strong>of</strong><br />

Venezuela. The study area is bounded on <strong>the</strong> north by <strong>the</strong> Río Orinoco. It includes all<br />

<strong>of</strong> <strong>the</strong> Territorio Federal Amazonas, Estado Bolívar, <strong>and</strong> part <strong>of</strong> Estado Delta<br />

Amacuro. The original resource assessment publication <strong>USGS</strong> Bulletin 2062 consists<br />

<strong>of</strong> 121 pages <strong>of</strong> text <strong>and</strong> figures as well as eight full-color maps:<br />

Geographic<br />

Geologic <strong>and</strong> tectonic<br />

Bouguer gravity<br />

Two mineral-occurrence maps<br />

Side-looking airborne radar image<br />

Two permissive domain maps<br />

The side-looking airborne radar image <strong>and</strong> <strong>the</strong> Bouguer gravity map are not<br />

included in this CD-ROM. The geology layer from <strong>the</strong> 1993 Bulletin was revised <strong>and</strong><br />

published as a series <strong>of</strong> MF <strong>and</strong> I maps:<br />

Quadrangles Map Authors<br />

--------------------------------------------------------------------<br />

Guri + Tucupita MF-2242 Cox <strong>and</strong> o<strong>the</strong>rs, 1993<br />

Ciudad Piar + MF-2246 Stewart <strong>and</strong> o<strong>the</strong>rs, 1994<br />

Ciudad Bolivar<br />

San Fern<strong>and</strong>o de MF-2247 Stewart, 1994<br />

Apure<br />

Santa Elena unpublished data Floyd Gray <strong>and</strong> o<strong>the</strong>rs, 1995<br />

Río Caura I-2537 Brooks <strong>and</strong> o<strong>the</strong>rs, 1995<br />

Puerto Ayacucho MF-2245 Wynn <strong>and</strong> o<strong>the</strong>rs, 1994<br />

La Esmeralda MF-2244 Wynn <strong>and</strong> o<strong>the</strong>rs, 1994<br />

Atabapo MF-2240 Wynn <strong>and</strong> o<strong>the</strong>rs, 1994<br />

Río Mavaca MF-2241 Wynn <strong>and</strong> o<strong>the</strong>rs, 1994<br />

Piedra de Cocuy MF-2243 Wynn <strong>and</strong> o<strong>the</strong>rs, 1994<br />

The digital map files on this CD-ROM were used to create <strong>the</strong> above<br />

publications. They subsequently underwent minor revisions to reconcile conflicting<br />

rock unit names <strong>and</strong> to view correctly in ArcView 1.

---

<strong>USGS</strong> BULLETIN 2062 TEXT AND FIGURES FILES<br />

The text <strong>of</strong> <strong>the</strong> 1993 <strong>USGS</strong> Bulletin 2062 is available in several Framemaker,<br />

Rich Text Word, <strong>and</strong> TIF files on <strong>the</strong> CD-ROM. The text in <strong>the</strong> following files may<br />

vary slightly from <strong>the</strong> final publication. Some <strong>of</strong> <strong>the</strong> files listed below duplicate parts<br />

<strong>of</strong> each o<strong>the</strong>r but in different formats. The tif files were created by scanning <strong>the</strong><br />

published Plates 2 <strong>and</strong> 6. Plate 2 is split into two files. The o<strong>the</strong>r Plates have not been<br />

scanned.<br />

size<br />

file name Kb format content<br />

b2062con.mif 154 framemaker 3.0p1b table <strong>of</strong> contents<br />

b2062con.txt 7.6 text table <strong>of</strong> contents<br />

b2062con.rtf 16 rich text (RTF) table <strong>of</strong> contents<br />

b2062fnt.mif 134 framemaker 3.0p1b cover 1, cover 2, i, ii, iii<br />

b2062fnt.txt 3.4 text i, ii<br />

b2062txt.mif 1208 framemaker 3.0p1b main body, p. 1-120<br />

b2062txt.txt 251 text main body, p. 1-72<br />

b2062txt.rtf 9.6 rich text (RTF) main body, p. 3-5<br />

tables.doc 113 Word 5.1 tables 1-2, 4-11<br />

tabside.doc 183 Word 5.1 table 3<br />

vzge.tif 93000 TIF Plate 2, geologic map part<br />

vzget.tif 20000 TIF Plate 2, geology, key part<br />

vzmin.tif 87000 TIF Plate 6, mineral deposits

---

REFERENCES FOR THIS DISC<br />

Bellizzia-G., Alirio, Pimentel-M., Nelly, <strong>and</strong> Bajo-O., R., 1976, Mapa geológico<br />

estructural de Venezuela: Ministerio de Minas e Hidrocarburos, Dirección<br />

Geológica, Caracas, Venezuela, scale 1:500,000.<br />

Briceño, H.O., 1982, Application <strong>of</strong> remote sensing to diamond placer exploration in a<br />

tropical jungle environment, Caroní River, Venezuela: Golden, Colo., Colorado<br />

School <strong>of</strong> Mines, Ph.D dissertation, 176 p.<br />

Brooks, W.E., Sidder, G.B., Wynn, J.C., Cox, D.P., Stewart, J.H., <strong>and</strong> Schruben, P.G.,<br />

1995, Geologic map <strong>of</strong> <strong>the</strong> Río Caura 2° by 3° quadrangle, estado Bolivar,<br />

Venezuela: U.S. Geological Survey Miscellaneous Investigations Map I-2537.<br />

Brooks, W.E., Tosdal, R.M., <strong>and</strong> Nuñez, F., in press, Gold resources <strong>of</strong> <strong>the</strong> Río Chivao<br />

study area, Estado Bolívar, Venezuela, in Sidder, G.B., García G., Andrés, <strong>and</strong><br />

Stoeser, J.W., eds., <strong>Geology</strong> <strong>and</strong> mineral deposits <strong>of</strong> <strong>the</strong> <strong>Venezuelan</strong> Guayana<br />

Shield: U.S. Geological Survey Bulletin 2124.<br />

Cox, D.P., Gray, Floyd, Acosta, Juan, Stewart, J.H., Arespón, Jesús, Brooks, W.E.,<br />

Franco, Luis, Salazar, Edixon, <strong>and</strong> Lopez, Yol<strong>and</strong>a, 1993, Geologic map <strong>of</strong> <strong>the</strong> Guri<br />

<strong>and</strong> sou<strong>the</strong>rn part <strong>of</strong> <strong>the</strong> Tucupita 2°x3° quadrangles, Bolivar State, Venezuela:<br />

U.S. Geological Survey Miscellaneous Field Studies Map MF-2242, scale 1:500,000.<br />

Environmental Systems Research Institute, Inc., 1990, ARC/INFO 5.0 User Manuals:<br />

Redl<strong>and</strong>s, Calif.<br />

Environmental Systems Research Institute, Inc., 1992, ArcView User's Guide:<br />

Redl<strong>and</strong>s, Calif.<br />

Gaudette, H.E., Mendoza, Vicente, Hurley, P.M., <strong>and</strong> Fairbairn, H.W., 1978, <strong>Geology</strong><br />

<strong>and</strong> age <strong>of</strong> <strong>the</strong> Parguaza rapakivi granite, Venezuela: Geological Society <strong>of</strong><br />

America Bulletin, v. 89, p. 1335-1340.<br />

Gaudette, H.E., <strong>and</strong> Olszewski, W.J., Jr., 1985, Geochronology <strong>of</strong> <strong>the</strong> basement rocks,<br />

Amazonas Territory, Venezuela <strong>and</strong> <strong>the</strong> tectonic evolution <strong>of</strong> <strong>the</strong> western Guiana<br />

Shield: Geologie en Mijnbouw, v. 64, p. 131-143.<br />

Ghosh, S.K., 1985, <strong>Geology</strong> <strong>of</strong> <strong>the</strong> Roraima Group <strong>and</strong> its implications: Simposium<br />

Amazonico, 1st, Caracas, 1981; Ministerio de Energía y Minas, Dirección de<br />

Geología Boletín de Geología Publicación Especial 10, p. 31-50<br />

Green, G.N., <strong>and</strong> Selner, G.I., 1988, GSMARC--A program <strong>and</strong> procedure to convert<br />

GSMAP data bases into ARC/INFO coverages; GSDARC, a counterpart program<br />

for GSDRAW data bases <strong>and</strong> an ARC/INFO procedure to topologically structure<br />

resultant data: U.S. Geological Survey Open-File Report 88-430-A (16 p.) <strong>and</strong> B (a<br />

5.25-inch diskette).

---

Marcano, Iris, Lugo, Elis, <strong>and</strong> Rivero, Nelson, 1991, Geología y geomorfología de la<br />

frontera con Colombia, entre la Piedra de Cocuy y Maroa, al suroeste del Territorio<br />

Federal Amazonas, Venezuela: CVG-TECMIN Grupo Inventario internal report.<br />

Martínez, Felix, 1991, Mapa geológico del area Río Cunucunuma: Congreso Geológico<br />

de la Frontiera de Venezuela, San Cristobal, Venezuela, September 9-13, 1991.<br />

McC<strong>and</strong>less, G.C., 1962, Reconnaissance geology <strong>of</strong> <strong>the</strong> northwest region <strong>of</strong> <strong>the</strong> State<br />

<strong>of</strong> Bolívar, Venezuela: Caribbean Journal <strong>of</strong> Science, v. 2, no. 4, p. 145-155.<br />

Mendoza, Vicente, Moreno, L.A., Barrios, Fern<strong>and</strong>o, Rivas, Duggar, Martínez, Jesús,<br />

Lira, Pedro, Sardi, Gustavo, <strong>and</strong> Ghosh, S.K., 1977, Geología de la parte norte del<br />

Territorio Federal Amazonas, Venezuela (informe en progreso): Congreso<br />

Geológico Venezolano, 5th, Caracas, 1977, Memoria, v.1, p. 363-404.<br />

Mendoza-S., Vicente, 1977, Evolución tectónica del Escudo de Guayana, in Petzall, C.,<br />

ed., Memoria Segundo [II] Congreso Latinoamericano de Geología, Tomo III,<br />

Caracas, November 11-16, 1973: Venezuela, Dirección de Geología, Boletin de<br />

Geología, Publicación Especial 7, v. 3, p. 2237-2270.<br />

Reid, A.R., <strong>and</strong> Bisque, R.E., 1975, Stratigraphy <strong>of</strong> <strong>the</strong> diamond-bearing Roraima<br />

Group, Estado Bolívar, Venezuela: Colorado School <strong>of</strong> Mines Quarterly Bulletin, v.<br />

70, no. 1, p. 61-82.<br />

Schruben, P.G., 1986, MRDS-REV, a mineral occurrence/deposit database for<br />

microcomputer: U.S. Geological Survey Open-File Report 86-34, 55 p.<br />

Schruben, P.G., 1995, <strong>Geology</strong> <strong>of</strong> <strong>the</strong> <strong>Venezuelan</strong> Guayana Shield at 1:500,000 scale--A<br />

digital representation <strong>of</strong> maps published by <strong>the</strong> U.S. Geological Survey: U.S.<br />

Geological Survey Open-File Report 95-493, 11 p. <strong>and</strong> a web page.<br />

Selner, G.I., <strong>and</strong> Taylor, R.B., 1987, GSDRAW <strong>and</strong> GSMAP version 4.0; prototype<br />

programs for <strong>the</strong> IBM PC <strong>and</strong> compatible microcomputers to assist compilation<br />

<strong>and</strong> publication <strong>of</strong> geologic maps <strong>and</strong> illustrations: U.S. Geological Survey Open-<br />

File Report 87-496-A (documentation, 90 p.), B (executable 5.25-inch diskette), C<br />

(source-code 5.25-inch diskette), <strong>and</strong> D (two executable utility program diskettes,<br />

each 5.25 inches).<br />

Sidder, G.B., <strong>and</strong> Mendoza-S., Vicente, 1991, <strong>Geology</strong> <strong>of</strong> <strong>the</strong> <strong>Venezuelan</strong> Guayana<br />

Shield <strong>and</strong> its relation to <strong>the</strong> entire Guayana Shield: U.S. Geological Survey Open-<br />

File Report 91-141, 59 p., 2 plates.<br />

Sidder, G.B., García G., Andrés, <strong>and</strong> Stoeser, J.W., eds., in press, <strong>Geology</strong> <strong>and</strong> mineral<br />

deposits <strong>of</strong> <strong>the</strong> <strong>Venezuelan</strong> Guayana Shield: U.S. Geological Survey Bulletin 2124.<br />

Soares, M.A., 1985, Estudio petrográfico de la estructura alcalina La Churuata,<br />

Territorio Federal Amazonas: Congreso Geológico Venezolano, 6th, Caracas,<br />

Memoria, v. 4, p. 2117-2158.

---

Stewart, J.H., 1994, Geologic map <strong>of</strong> part <strong>of</strong> <strong>the</strong> San Fern<strong>and</strong>o de Apure 2°x3°<br />

quadrangle, Venezuela: U.S. Geological Survey Miscellaneous field studies map<br />

MF-2247.<br />

Stewart, J.H., Martínez, Félix, <strong>and</strong> Brooks, W.E., 1994, Geologic map <strong>of</strong> <strong>the</strong> Ciudad<br />

Piar <strong>and</strong> part <strong>of</strong> <strong>the</strong> Ciudad Bolivar 2°x3° quadrangles, Bolivar State, Venezuela:<br />

U.S. Geological Survey Miscellaneous Field Studies Map MF-2246, scale 1:500,000.<br />

Teggin, D.E., Martínez, M., <strong>and</strong> Palacios, G., 1985, Un estudio preliminar de las<br />

diabasas del Estado Bolívar, Venezuela, in Espejo C., Aníbal, Ríos-F., J.H., Pimentel<br />

de Bellizzia, Nelly, <strong>and</strong> Pardo, A.S., eds., Petrología, geoquímica, y geocronología,<br />

VI Congreso Geológico Venezolano, Caracas, Memoria, v. 4, p. 2159-2206.<br />

U.S. Geological Survey, 1986, Digital line graphs from 1:24,000-scale maps: U.S.<br />

Geological Survey US GeoData Data Users Guide 1, 109 p.<br />

U.S. Geological Survey, 1987, Digital line graphs from 1:2,000,000-scale maps: U.S.<br />

Geological Survey US GeoData Data Users Guide 3, 71 p.<br />

U.S. Geological Survey, 1989, Digital line graphs from 1:100,000-scale maps: U.S.<br />

Geological Survey US GeoData Data Users Guide 2, 88 p.<br />

U.S. Geological Survey <strong>and</strong> Corporación Venezolana de Guayana, Técnica Minera,<br />

C.A., 1993, <strong>Geology</strong> <strong>and</strong> Mineral <strong>Resource</strong> <strong>Assessment</strong> <strong>of</strong> <strong>the</strong> <strong>Venezuelan</strong> Guayana<br />

Shield: U.S. Geological Survey, Bulletin 2062, 121 p. 8 plates.<br />

Wentworth, C.M., <strong>and</strong> Fitzgibbon, T.T., 1991, Alacarte user manual, version 1.0: U.S.<br />

Geological Survey Open-File Report 91-587-C, 267 p.<br />

Wynn, J.C., Olmore, S.D., Mendoza, Vicente, Martínez, Miguel, Rincón, Haydée,<br />

García, Andrés, Rivero, Nelson, Rendón, Inés, Marcano, Iris, Lugo, Elis, <strong>and</strong><br />

Schruben, P.G., 1994, Geologic map <strong>of</strong> <strong>the</strong> Venezuela part <strong>of</strong> <strong>the</strong> Atabapo 2°x3°<br />

quadrangle, Amazonas Federal Territory, Venezuela: U.S. Geological Survey<br />

Miscellaneous Field Studies Map MF-2240, scale 1:500,000.<br />

Wynn, J.C., Olmore, S.D., Mendoza, Vicente, García, Andrés, Martínez, Miguel, <strong>and</strong><br />

Schruben, P.G., 1994, Geologic map <strong>of</strong> <strong>the</strong> Venezuela part <strong>of</strong> <strong>the</strong> Río Mavaca 2°x3°<br />

quadrangle, Amazonas Federal Territory, Venezuela: U.S. Geological Survey<br />

Miscellaneous Field Studies Map MF-2241, scale 1:500,000.<br />

Wynn, J.C., Olmore, S.D., Mendoza, Vicente, García, Andrés, Martínez, Miguel, Tovar,<br />

Frank, Rendón, Inés, Rincón, Haydée, Martínez, Félix, Lugo, Elis, <strong>and</strong> Schruben,<br />

P.G., 1994, Geologic map <strong>of</strong> <strong>the</strong> Venezuela part <strong>of</strong> <strong>the</strong> La Esmeralda 2°x3°<br />

quadrangle, Amazonas Federal Territory, Venezuela: U.S. Geological Survey<br />

Miscellaneous Field Studies Map MF-2244, scale 1:500,000.<br />

Wynn, J.C., Olmore, S.D., Mendoza, Vicente, García, Andrés, Rendón, Inés, Estanga,<br />

Yasmin, Rincón, Haydée, Martínez, Félix, Lugo, Elis, Rivero, Nelson, <strong>and</strong><br />

Schruben, P.G., 1994, Geologic map <strong>of</strong> <strong>the</strong> Venezuela part <strong>of</strong> <strong>the</strong> Puerto Ayacucho

---

2°x3° quadrangle, Amazonas Federal Territory, Venezuela: U.S. Geological Survey<br />

Miscellaneous Field Studies Map MF-2245, scale 1:500,000.<br />

Wynn, J.C., Olmore, S.D., Mendoza, Vicente, Rincón, Haydée, García, Andrés, Rivero,<br />

Nelson, Rendón, Inés, Gray, Floyd, Marcano, Iris, Lugo, Elis, <strong>and</strong> Schruben, P.G.,<br />

1994, Geologic map <strong>of</strong> <strong>the</strong> Venezuela part <strong>of</strong> <strong>the</strong> Piedra de Cocuy 2°x3°<br />

quadrangle, Amazonas Federal Territiory, Venezuela: U.S. Geological Survey<br />

Miscellaneous Field Studies Map MF-2243, scale 1:500,000.

---

DIGITAL PRODUCTION TECHNIQUES<br />

The linework for all <strong>the</strong> quadrangles was originally digitized by Jeff Wynn with<br />

GSMAP (Selner <strong>and</strong> Taylor, 1987), a <strong>USGS</strong>-authored map editing <strong>and</strong> publishing<br />

program. Conversion from GSMAP to ARC/INFO was accomplished with GSMARC<br />

(Green <strong>and</strong> Selner, 1988). The three nor<strong>the</strong>rn quadrangles were later re-scanned on an<br />

Tektronix 4991 autovectorizing drum scanner by Paul Schruben from <strong>the</strong> geologists'<br />

revised drawings. The arcs <strong>and</strong> polygons were tagged in ARC/INFO <strong>and</strong> <strong>the</strong><br />

oriented point symbols such as bedding <strong>and</strong> joint symbols were created with Alacarte<br />

(Wentworth <strong>and</strong> Fitzgibbon, 1991).<br />

MAP PROJECTION<br />

The map projection is Equidistant Conic with <strong>the</strong> following parameters for all<br />

quadrangles:<br />

Sphere Clarke 1866 spheroid<br />

1st st<strong>and</strong>ard parallel 9 0 0.000<br />

2nd st<strong>and</strong>ard parallel 4 0 0.000<br />

central meridian -66 0 0.000<br />

latitude <strong>of</strong> projection's origin 0 0 0.000<br />

false easting (meters) 0.00000<br />

false northing (meters) 0.00000

---

CAUTIONS RELATING TO USE OF THE MAPS<br />

One <strong>of</strong> <strong>the</strong> advantages <strong>of</strong> digital maps is <strong>the</strong> ability to change <strong>the</strong> map scale.<br />

However, <strong>the</strong> users <strong>of</strong> this disc should respect <strong>the</strong> intentions <strong>of</strong> <strong>the</strong> authors <strong>and</strong><br />

recognize certain limitations <strong>of</strong> digital maps. The <strong>Venezuelan</strong> MF series maps on this<br />

disc are intended to be used at a scale <strong>of</strong> 1:500,000; <strong>the</strong>y are not intended to be used at<br />

a more detailed (larger) scale. A Venezuela 2°x3° degree quadrangle measures about<br />

17 inches high by 26 inches wide at 1:500,000 scale.<br />

The "quadrangle" maps in this publication cover somewhat more or less than<br />

2°x3° depending on <strong>the</strong> specific map. For instance, <strong>the</strong> Guri map (Cox <strong>and</strong> o<strong>the</strong>rs,<br />

1993) contains all <strong>of</strong> <strong>the</strong> Guri quadrangle <strong>and</strong> <strong>the</strong> sou<strong>the</strong>rn part <strong>of</strong> <strong>the</strong> Tucupita<br />

quadrangle. The entire study area in <strong>the</strong> sou<strong>the</strong>ast part <strong>of</strong> Venezuela, known as <strong>the</strong><br />

<strong>Venezuelan</strong> Guayana Shield, is about 36 inches tall at 1:1 million scale, which is <strong>the</strong><br />

published scale for Bulletin 2062 (<strong>USGS</strong> <strong>and</strong> Corporación Venezolana de Guayana,<br />

Técnica Minera, C.A., 1993).<br />

Fur<strong>the</strong>rmore, <strong>the</strong> geologic map is primarily a bedrock map, which depicts<br />

geologic materials present beneath <strong>the</strong> soil or relatively thin mantles <strong>of</strong> surficial<br />

deposits, not necessarily <strong>the</strong> surficial materials <strong>the</strong>mselves. Indeed, <strong>the</strong> study area<br />

contains so much surficial cover <strong>and</strong> st<strong>and</strong>ing water that much <strong>of</strong> <strong>the</strong> mapping was<br />

accomplished with geophysical methods as opposed to directly examining rock<br />

outcrops.

---

ONLINE FILES<br />

Some <strong>of</strong> <strong>the</strong> files on this CD will be available on <strong>the</strong> internet at <strong>the</strong> following<br />

internet address:<br />

http://minerals.er.usgs.gov/vz/dds-46.html<br />

The page will also list any bugs <strong>and</strong> errors discovered in <strong>the</strong> CD-ROM after<br />

release.

---

1) ARC/INFO Export<br />

GRAPHICS FORMATS AVAILABLE ON THE DISC<br />

These coverages are used for spatial analysis, derivative products, <strong>and</strong> to-scale<br />

plots on <strong>the</strong> Versatec electrostatic plotter. Compatible with Environmental Systems<br />

Research Institute's ARC/INFO Version 6.1.2 or later. The files are simple text <strong>and</strong><br />

should be transmitted in ASCII mode except for <strong>the</strong> *.gra plot files, which are binary.<br />

2) ARC/INFO Graphics, Adobe Illustrator, Portable Document Format (PDF), <strong>and</strong><br />

Postscript formats<br />

The geologic map in ARC/INFO Graphics, Adobe Illustrator, PDF, <strong>and</strong> Postscript<br />

formats are located in directory “arcunix7/vz”. All are derived from <strong>the</strong> ARC/INFO<br />

“.gra” file using <strong>the</strong> POSTSCRIPT comm<strong>and</strong>.<br />

3) ArcView format<br />

ArcView is an easy-to-use graphics display package by <strong>the</strong> authors <strong>of</strong><br />

ARC/INFO. This CD-ROM contains ArcView coverages for both UNIX <strong>and</strong> Micros<strong>of</strong>t<br />

Windows 3.x. It also contains export files that can be copied to o<strong>the</strong>r ARC/INFO<br />

platforms <strong>and</strong> imported to ArcView. ArcView 1 keys are in <strong>the</strong> “arcunix6” directory.<br />

The ArcView 3 key for <strong>the</strong> “vz” directory is in <strong>the</strong> “arcunix7”directory.<br />

4) U.S. Geological Survey Digital Line Graph (DLG) Optional format (U.S. Geological<br />

Survey, 1986, 1987, <strong>and</strong> 1989).<br />

The DLG Optional format is a U.S. Geological Survey st<strong>and</strong>ard for storing<br />

topologically structured files. It results in a compact ASCII file that is compatible with<br />

a variety <strong>of</strong> graphics s<strong>of</strong>tware. Only <strong>the</strong> geology, faults, <strong>and</strong> correlation chart layers<br />

were converted to this format. The polygons <strong>and</strong> arcs are tagged, but <strong>the</strong> text<br />

annotation is not present because <strong>the</strong> DLG conversion s<strong>of</strong>tware does not support<br />

annotation.<br />

5) Tagged image file format (TIFF)<br />

The geologic map <strong>and</strong> mineral deposit maps from Bulletin 2062 were scanned<br />

on a color scanner <strong>and</strong> saved as TIFF files. The larger files are compressed under<br />

PKZIP.

---

ARCVIEW AND ARC/INFO FILES<br />

These files are compatible with ArcView 1 <strong>and</strong> ARC/INFO Version 6.1.2 or<br />

later. The files are contained in 11 directories. Ten <strong>of</strong> those directories contain<br />

coverages for <strong>the</strong> individual quadrangle publications. The eleventh directory, "vz",<br />

contains <strong>the</strong> same information but in <strong>the</strong> form <strong>of</strong> a combined map with all <strong>the</strong><br />

quadrangles tiled toge<strong>the</strong>r into a single coverage. ArcView 1 keys are in <strong>the</strong><br />

“arcunix6” directory. The ArcView 3 key for <strong>the</strong> “vz” directory is in <strong>the</strong><br />

“arcunix7”directory. There are no ArcView 3 keys for <strong>the</strong> individual quadrangles.<br />

The coverages for <strong>the</strong> individual quadrangles have <strong>the</strong> same features as <strong>the</strong><br />

combined coverage. The only differences are in some <strong>of</strong> <strong>the</strong> file names. For instance,<br />

<strong>the</strong> place names <strong>and</strong> city points in <strong>the</strong> individual quadrangles are stored in files called<br />

"*anno5.e00" as opposed to "places.e00" for <strong>the</strong> combined coverage.<br />

The 11 directory structure is repeated in each <strong>of</strong> three formats: export, raw<br />

UNIX, <strong>and</strong> PC ARCVIEW.<br />

EXPORT FILES<br />

The export files are stored in <strong>the</strong> "export" directory. The same export files are<br />

used for both ARCVIEW <strong>and</strong> ARC/INFO. Each directory contains an IMPORT.AML<br />

program which imports all <strong>the</strong> coverages, lookup tables, etc. The "vz" directory<br />

contains lookup tables <strong>and</strong> markersets necessary for plotting <strong>the</strong> individual<br />

quadrangles. Before launching ARCVIEW, <strong>the</strong> "av.mrk" <strong>and</strong> "av.txt" files should be<br />

copied to <strong>the</strong> ARCVIEW home directory, usually <strong>the</strong> root or login directory.<br />

The directories containing <strong>the</strong> export files on <strong>the</strong> CD are actually ARC/INFO<br />

workspaces for UNIX. For o<strong>the</strong>r platforms it may be necessary to launch ARC/INFO,<br />

create each <strong>of</strong> <strong>the</strong> 11 workspaces <strong>and</strong> import <strong>the</strong> coverages from those new<br />

workspaces. For instance, for <strong>the</strong> "vz" directory:<br />

arc<br />

cw vz<br />

q<br />

cd vz<br />

cp /pdd/dds46/export/vz/* .<br />

arc<br />

&r import<br />

The directory structure on <strong>the</strong> CD is as follows:<br />

export main directory<br />

at Atabapo<br />

ay Puerto Ayacucho<br />

ca Río Caura<br />

es La Esmeralda<br />

gu Guri, Tucupita<br />

ma Río Mavaca<br />

pc Piedra de Cocuy

---

pi Ciudad Piar, Ciudad Bolivar<br />

se Santa Elena<br />

sf San Fern<strong>and</strong>o de Apure<br />

vz combined coverages. Also necessary to plot individual quads.<br />

RAW UNIX COVERAGES:<br />

The raw coverages are in directory "arcunix6" <strong>and</strong> “arcunix7”. These can be<br />

copied to your UNIX machine with <strong>the</strong> following comm<strong>and</strong>:<br />

cp -r /pdd/dds46/arcunix<br />

PC ARCVIEW COVERAGES:<br />

The PC ARCVIEW coverages are stored in directory "arcpc". These files were<br />

converted directly from <strong>the</strong> UNIX version with <strong>the</strong> C program PCWKSP.<br />

RUNNING THE PLOT PROGRAMS<br />

Each <strong>of</strong> <strong>the</strong> 11 directories contains a plot program for that area. The plot<br />

programs rely on lookup tables in <strong>the</strong> "vz” combined coverages directory. So <strong>the</strong><br />

"vz” combined coverages directory should be copied or imported to hard disk before<br />

executing <strong>the</strong> plot program. The resulting .gra file was converted to PostScript .eps<br />

with <strong>the</strong> ARC POSTSCRIPT comm<strong>and</strong>. The polygon colors are for a Versatec plotter<br />

or display screen.

---

INSTALLING ARCVIEW 1<br />

This section contains instructions for installing <strong>and</strong> launching<br />

ArcView 1 for Windows <strong>and</strong> launching instructions for ArcView 1 for UNIX.<br />

Installation instructions for ArcView 1 for Micros<strong>of</strong>t Windows:<br />

1) Please observe <strong>the</strong> following system requirements:<br />

80386 or better CPU<br />

Math coprocessor recommended<br />

Windows 3.0 or higher but not Windows 95<br />

4 Mb <strong>of</strong> RAM, 8 strongly recommended<br />

15 Mb <strong>of</strong> disk space<br />

Super VGA graphics system, 256 colors, 640x480 pixels minimum,<br />

1024x768 pixels strongly recommended<br />

Micros<strong>of</strong>t compatible mouse<br />

Windows-supported printer<br />

2) Decide where you are going to put ArcView 1 on your hard drive. You must have<br />

15 Mb <strong>of</strong> hard disk space.<br />

3) Launch Windows. Launch <strong>the</strong> File Manager. Use <strong>the</strong> File Manager to find <strong>the</strong> CD-<br />

ROM drive <strong>and</strong> <strong>the</strong> \DDS46\ARCVIEW directory. Double-click on<br />

ARCVIEW.EXE. This starts <strong>the</strong> self-installing procedure. At <strong>the</strong> licensing agreement<br />

document select <strong>the</strong> File menu, Exit. ARCVIEW asks for a hard disk drive letter<br />

designation <strong>and</strong> a directory name to store <strong>the</strong> program. The default is \ARCVIEW1.<br />

4) When <strong>the</strong> install finishes, ArcView will tell you to examine SETUP.TXT <strong>and</strong> use it<br />

to modify AUTOEXEC.BAT <strong>and</strong> CONFIG.SYS. Exit from Windows <strong>and</strong> use <strong>the</strong><br />

following instructions modified from SETUP.TXT.<br />

Add <strong>the</strong> following environment variables to <strong>the</strong> C:\AUTOEXEC.BAT file:<br />

set AVHOME=c:\arcview1 (or wherever you decide to put it)<br />

set PATH=%PATH%;%AVHOME%\bin (Add Arcview1's bin directory<br />

to <strong>the</strong> path )<br />

set HOME=c:\arcview1 (or wherever you decide to put it)<br />

set TEMP=c:\temp (Make sure <strong>the</strong> directory<br />

exists. A RAM disk works <strong>the</strong><br />

best, i.e, TEMP=d:\. This<br />

variable should already be<br />

present if Windows has been<br />

installed.)<br />

Add <strong>the</strong> following line to <strong>the</strong> C:\CONFIG.SYS file:<br />

FILES=65

---

Rename <strong>the</strong> original lineset. Copy <strong>the</strong> custom lineset from <strong>the</strong> DDS-46 CD- ROM.<br />

CD C:\ARCVIEW1\SYMBOLS<br />

REN AV.LIN AV_ORIG.LIN<br />

COPY D:\DDS46\DATAFILE\AVPCCOV\AV.LIN<br />

5) Launch Windows. Launch <strong>the</strong> File Manager again <strong>and</strong> copy <strong>the</strong> DDS46\ARCPC<br />

directory to your hard disk. This step is optional but ArcView runs very slowly if <strong>the</strong><br />

coverages are located on <strong>the</strong> CD-ROM.<br />

Double-click on <strong>the</strong> ArcView icon. Navigate <strong>the</strong> drive <strong>and</strong> directory menus to<br />

D:\DDS46\DATAFILE. Double-click on <strong>the</strong> COSTA.AV view. ArcView will ask to<br />

search for <strong>the</strong> GEOL coverage. Select "Yes". Navigate to <strong>the</strong> AVPCCOV folder <strong>and</strong><br />

double-click on <strong>the</strong> GEOL file. The ArcView Teacher will automatically find <strong>the</strong> full<br />

path to <strong>the</strong> rest <strong>of</strong> <strong>the</strong> coverages <strong>and</strong> launch <strong>the</strong> view. Select <strong>the</strong> "File" menu, "Save<br />

As". Save <strong>the</strong> view so <strong>the</strong> next time you launch it, <strong>the</strong> path will be remembered.

---

USING ARCVIEW 1<br />

The CD-ROM includes coverages that can be displayed with ArcView 1<br />

(Environmental Systems Research Institute, Inc., 1992). ArcView is an easyto-use<br />

graphics display package by <strong>the</strong> authors <strong>of</strong> ARC/INFO. ArcView<br />

displays <strong>the</strong> same coverages <strong>and</strong> images as ARC/INFO. ArcView 1 is available<br />

for both UNIX <strong>and</strong> Micros<strong>of</strong>t Windows 3.x computers. This CD-ROM contains ArcView<br />

for Windows 3.x programs but not ArcView for UNIX programs. It does, however,<br />

contain coverages <strong>and</strong> views for both types <strong>of</strong> computers.<br />

See "Installing ArcView 1" for instructions on installing <strong>and</strong> launching ArcView<br />

1. After ArcView is launched, <strong>the</strong> Table <strong>of</strong> Contents or map key appears on <strong>the</strong> left<br />

<strong>and</strong> <strong>the</strong> map on <strong>the</strong> right. ArcView has a time-saving feature called interruptible redraw.<br />

This means that <strong>the</strong> tools, menu items <strong>and</strong> <strong>the</strong>mes in <strong>the</strong> Table <strong>of</strong> Contents are<br />

selectable even while ArcView is re-drawing <strong>the</strong> map. A mouse-click or mouse-drag<br />

will interrupt <strong>the</strong> drawing <strong>and</strong> take effect within a few seconds. There is no need to<br />

wait for complicated maps to finish drawing if you already know what you want to<br />

do next.<br />

The initial width <strong>of</strong> <strong>the</strong> Table <strong>of</strong> Contents is too narrow to see all <strong>the</strong> text in <strong>the</strong><br />

key. The width can be increased by dragging on <strong>the</strong> edge <strong>of</strong> <strong>the</strong> table with <strong>the</strong> mouse.<br />

Increasing <strong>the</strong> width <strong>of</strong> <strong>the</strong> Table <strong>of</strong> Contents causes it to overlap <strong>the</strong> map, but <strong>the</strong><br />

map can be brought to <strong>the</strong> foreground by clicking on its title bar or edge.<br />

The individual layers (data <strong>the</strong>mes) in <strong>the</strong> Table <strong>of</strong> Contents are turned on <strong>and</strong><br />

<strong>of</strong>f in <strong>the</strong> display by selecting <strong>the</strong> checkboxes along <strong>the</strong> left side <strong>of</strong> <strong>the</strong> map key.<br />

Legends below individual <strong>the</strong>mes can be turned on <strong>and</strong> <strong>of</strong>f by dragging on <strong>the</strong><br />

triangle on <strong>the</strong> right side <strong>of</strong> <strong>the</strong> key. Colors <strong>of</strong> points, lines, <strong>and</strong> polygon fill can be<br />

changed by double-clicking a <strong>the</strong>me, selecting <strong>the</strong> legend checkbox in <strong>the</strong> Properties<br />

dialog, <strong>the</strong>n double-clicking on <strong>the</strong> color.<br />

Zooming in <strong>and</strong> out are accomplished in many ways in ArcView. One way is<br />

to select a <strong>the</strong>me or <strong>the</strong>mes by single-clicking on <strong>the</strong> items in <strong>the</strong> Table <strong>of</strong> Contents so<br />

<strong>the</strong>y appear slightly raised. Single-click again to de-select <strong>the</strong>m. Choose just <strong>the</strong> items<br />

you want to zoom to, <strong>the</strong>n select <strong>the</strong> "fit-selected-features-to-window" icon, which is<br />

<strong>the</strong> second icon from <strong>the</strong> left in <strong>the</strong> map window. It looks like a down arrow over a<br />

stack <strong>of</strong> paper. For instance, <strong>the</strong> "Venezuela national boundary" <strong>the</strong>me will give <strong>the</strong><br />

widest view, "Index map" <strong>the</strong> next widest, "<strong>Geology</strong>, all quadrangles" <strong>the</strong> next widest,<br />

<strong>and</strong> individual quadrangles <strong>the</strong> smallest. In each quadrangle, <strong>the</strong> Scale bar <strong>the</strong>me<br />

zooms out to see all <strong>the</strong> text <strong>and</strong> map. This is <strong>the</strong> default selection as <strong>the</strong> CD is<br />

shipped.<br />

Ano<strong>the</strong>r way to zoom in is with <strong>the</strong> "zoom-to-a-box" tool on <strong>the</strong> tool palette.<br />

The tool palette can be brought to <strong>the</strong> foreground with <strong>the</strong> "Windows" menu, "Tools..."<br />

item. Just select <strong>the</strong> dashed-line-box tool, which is <strong>the</strong> second from <strong>the</strong> bottom on <strong>the</strong><br />

left, <strong>the</strong>n drag in a diagonal movement across <strong>the</strong> area you wish to zoom to.<br />

If you view <strong>the</strong> "Rock unit names" <strong>the</strong>me, be sure to turn on <strong>the</strong> "Rock unit<br />

name leaders" as well. O<strong>the</strong>rwise some unit names appear to float in <strong>the</strong> wrong unit.<br />

The order <strong>of</strong> layers in <strong>the</strong> Table <strong>of</strong> Contents is critical. All layers are opaque,<br />

<strong>and</strong> <strong>the</strong> color-fill polygons obscure everything beneath <strong>the</strong>m. For this reason, color-fill<br />

<strong>the</strong>mes are positioned lowest on <strong>the</strong> key <strong>and</strong> duplicated as non-filled versions higher<br />

up in <strong>the</strong> key. For instance, "<strong>Geology</strong> polygons" is low in <strong>the</strong> Table <strong>of</strong> Contents<br />

because it obscures everything beneath it. There is also a non-filled version called<br />

"<strong>Geology</strong> arcs" higher up in <strong>the</strong> key. Should it be necessary to change <strong>the</strong> order <strong>of</strong>

---

items in <strong>the</strong> Table <strong>of</strong> Contents, <strong>the</strong>y can be dragged to a new position with <strong>the</strong> mouse.<br />

For instance, "Index map, colored countries" is positioned fairly high in <strong>the</strong> key for a<br />

color-fill <strong>the</strong>me. To draw geology outlines on top <strong>of</strong> it, just drag <strong>the</strong> index map <strong>the</strong>me<br />

to a position below <strong>the</strong> geology outlines <strong>the</strong>me.<br />

To create hard copy <strong>of</strong> <strong>the</strong> ArcView 1 graphics screen, select <strong>the</strong> camera icon on<br />

<strong>the</strong> main display screen. This creates an encapsulated PostScript (EPS) file <strong>of</strong> <strong>the</strong><br />

display image, which can be printed with st<strong>and</strong>ard commercial graphics s<strong>of</strong>tware.<br />

Use <strong>the</strong> "File" menu, "Open..." item to select o<strong>the</strong>r views:<br />

Area file name<br />

-------------------------------------------------------------------------<br />

<strong>Venezuelan</strong> Guayana Shield, all quadrangles vz.av<br />

Guri <strong>and</strong> sou<strong>the</strong>rn part <strong>of</strong> <strong>the</strong> Tucupita 2°x3° quadrangles gu.av<br />

Ciudad Piar <strong>and</strong> part <strong>of</strong> <strong>the</strong> Ciudad Bolivar 2°x3° quadrangles pi.av<br />

San Fern<strong>and</strong>o de Apure 2°x3° quadrangle (Bolivar part) sf.av<br />

Santa Elena 2°x3° quadrangle (Venezuela part) se.av<br />

Río Caura 2° by 3° quadrangle ca.av<br />

Puerto Ayacucho 2°x3° quadrangle (Venezuela part) ay.av<br />

La Esmeralda 2°x3° quadrangle (Venezuela part) es.av<br />

Atabapo 2°x3° quadrangle (Venezuela part) at.av<br />

Río Mavaca 2°x3° quadrangle (Venezuela part) ma.av<br />

Piedra de Cocuy 2°x3° quadrangle (Venezuela part) pc.av

---

ARCVIEW 1 FILES<br />

The following table shows <strong>the</strong> ArcView table <strong>of</strong> contents items <strong>and</strong> <strong>the</strong><br />

coverages <strong>the</strong>y are drawn from:<br />

ArcView views <strong>and</strong> <strong>the</strong>mes file name<br />

-------------------------------------------------------------------------<br />

<strong>Venezuelan</strong> Guayana Shield, all quadrangles vz.av<br />

Venezuela national boundary vzctry<br />

Venezuela province boundary vzprov<br />

Scale bar annotation scale<br />

Scale bar scale<br />

Place names places<br />

Place points places<br />

Roads vzrd<br />

Outer quad outline vzout<br />

Outer quad outline, lat/long numbers vzout<br />

Latitude/longitude tics vztc<br />

Index map annotation index<br />

Index map lat/long grid only grid<br />

Index map, colored countries, lat/long grid index<br />

Streams annotation vzst<br />

Streams vzst<br />

Mineral deposits deposit<br />

Linear features annotation vzft<br />

Linear features vzft<br />

A. Permissive domains annotation raanno<br />

A. Permissive domains leaders raanno<br />

A. Permissive domains for selected Fe, Au, Sn, ra<br />

Cu deposits<br />

A. Permissive domains poly arcs only ra<br />

B. Permissive domains structure annotation rbstruct<br />

B. Permissive domains structure lines rbstruct<br />

B. Permissive domains annotation rbanno<br />

B. Permissive domains leaders rbanno<br />

B. Permissive domains for selected Pb-Zn, Ni-Cu, rb<br />

diamond, kaolin deposits<br />

B. Permissive domains poly arcs only rb<br />

Correlation <strong>of</strong> map units annotation vzcor<br />

Correlation <strong>of</strong> map units polygons vzcor<br />

Buried magnetic bodies vzma<br />

Rock unit labels vzlab<br />

Rock unit labels leaders vzlab<br />

<strong>Geology</strong> arcs vzge<br />

<strong>Geology</strong> polygons vzge<br />

Guri <strong>and</strong> sou<strong>the</strong>rn part <strong>of</strong> <strong>the</strong> Tucupita 2°x3° gu.av<br />

quadrangles<br />

Index map, latitude/longitude tics vztc

---

Index map, annotation index<br />

Index map, lat/long grid only grid<br />

Index map, colored countries, lat/long grid index<br />

Guri, quadrangle lat/long tics gutc<br />

Guri, quadrangle lat/long numbers guout<br />

Guri, quadrangle outline guout<br />

Guri, place name annotation guanno5<br />

Guri, city points guanno5<br />

Guri, roads gurd<br />

Guri, province boundary gupl<br />

Guri, streams annotation gust<br />

Guri, streams gust<br />

Guri, linear feature annotation guft<br />

Guri, linear features guft<br />

Guri, correlation <strong>of</strong> map units annotation gucor<br />

Guri, correlation <strong>of</strong> map units polygons gucor<br />

Guri, map key annotation guleg<br />

Guri, map key points gulegpt<br />

Guri, map key arcs guleg<br />

Guri, map key polygons guleg<br />

Guri, scale bar annotation guscale<br />

Guri, scale bar guscale<br />

Guri, rock unit labels gulab<br />

Guri, rock unit labels leaders gulab<br />

Guri, geology arcs guge<br />

Guri, geology polygons guge<br />

Ciudad Piar <strong>and</strong> part <strong>of</strong> <strong>the</strong> Ciudad Bolivar 2°x3° pi.av<br />

quadrangles<br />

Index map, latitude/longitude tics vztc<br />

Index map, annotation index<br />

Index map, lat/long grid only grid<br />

Index map, colored countries, lat/long grid index<br />

Ciudad Piar, quadrangle lat/long tics pitc<br />

Ciudad Piar, quadrangle lat/long numbers piout<br />

Ciudad Piar, quadrangle outline piout<br />

Ciudad Piar, place name annotation pianno5<br />

Ciudad Piar, city points pianno5<br />

Ciudad Piar, roads pird<br />

Ciudad Piar, province boundary pipl<br />

Ciudad Piar, streams annotation pist<br />

Ciudad Piar, streams pist<br />

Ciudad Piar, linear feature annotation pift<br />

Ciudad Piar, linear features pift<br />

Ciudad Piar, structural trends from SLAR pisr<br />

Ciudad Piar, correlation <strong>of</strong> map units annotation picor<br />

Ciudad Piar, correlation <strong>of</strong> map units polygons picor<br />

Ciudad Piar, map key annotation pileg<br />

Ciudad Piar, map key points pilegpt<br />

Ciudad Piar, map key arcs pileg<br />

Ciudad Piar, map key polygons pileg<br />

Ciudad Piar, scale bar annotation piscale

---

Ciudad Piar, scale bar piscale<br />

Ciudad Piar, rock unit labels pilab<br />

Ciudad Piar, rock unit labels leaders pilab<br />

Ciudad Piar, kimberlite area annotation pima<br />

Ciudad Piar, kimberlite area pima<br />

Ciudad Piar, geology arcs pige<br />

Ciudad Piar, geology polygons pige<br />

San Fern<strong>and</strong>o de Apure 2°x3° quadrangle (Bolivar part) sf.av<br />

Index map, latitude/longitude tics vztc<br />

Index map, annotation index<br />

Index map, lat/long grid only grid<br />

Index map, colored countries, lat/long grid index<br />

San Fern<strong>and</strong>o, quadrangle lat/long tics sftc<br />

San Fern<strong>and</strong>o, quadrangle lat/long numbers sfout<br />

San Fern<strong>and</strong>o, quadrangle outline sfout<br />

San Fern<strong>and</strong>o, place name annotation sfanno5<br />

San Fern<strong>and</strong>o, city points sfanno5<br />

San Fern<strong>and</strong>o, province boundary sfpl<br />

San Fern<strong>and</strong>o, streams annotation sfst<br />

San Fern<strong>and</strong>o, streams sfst<br />

San Fern<strong>and</strong>o, linear features sfft<br />

San Fern<strong>and</strong>o, correlation <strong>of</strong> map units annotation sfcor<br />

San Fern<strong>and</strong>o, correlation <strong>of</strong> map units polygons sfcor<br />

San Fern<strong>and</strong>o, map key annotation sfleg<br />

San Fern<strong>and</strong>o, map key points sflegpt<br />

San Fern<strong>and</strong>o, map key arcs sfleg<br />

San Fern<strong>and</strong>o, map key polygons sfleg<br />

San Fern<strong>and</strong>o, scale bar annotation sfscale<br />

San Fern<strong>and</strong>o, scale bar sfscale<br />

San Fern<strong>and</strong>o, rock unit labels sflab<br />

San Fern<strong>and</strong>o, rock unit label leaders sflab<br />

San Fern<strong>and</strong>o, geology arcs sfge<br />

San Fern<strong>and</strong>o, geology polygons sfge<br />

Santa Elena 2°x3° quadrangle (Venezuela part) se.av<br />

Index map, latitude/longitude tics vztc<br />

Index map, annotation index<br />

Index map, lat/long grid only grid<br />

Index map, colored countries, lat/long grid index<br />

Santa Elena, quadrangle lat/long tics setc<br />

Santa Elena, quadrangle lat/long numbers seout<br />

Santa Elena, quadrangle outline seout<br />

Santa Elena, place name annotation seanno5<br />

Santa Elena, city points seanno5<br />

Santa Elena, roads serd<br />

Santa Elena, province boundary sepl<br />

Santa Elena, stream annotation sest<br />

Santa Elena, streams sest<br />

Santa Elena, linear feature annotation seft

---

Santa Elena, linear features seft<br />

Santa Elena, correlation <strong>of</strong> map units annotation secor<br />

Santa Elena, correlation <strong>of</strong> map units polygons secor<br />

Santa Elena, map key annotation seleg<br />

Santa Elena, map key points selegpt<br />

Santa Elena, map key arcs seleg<br />

Santa Elena, map key polygons seleg<br />

Santa Elena, scale bar annotation sescale<br />

Santa Elena, scale bar sescale<br />

Santa Elena, rock unit labels selab<br />

Santa Elena, rock unit labels leaders selab<br />

Santa Elena, geology arcs sege<br />

Santa Elena, geology polygons sege<br />

Río Caura 2° by 3° quadrangle ca.av<br />

Index map, latitude/longitude tics vztc<br />

Index map, annotation index<br />

Index map, lat/long grid only grid<br />

Index map, colored countries, lat/long grid index<br />

Río Caura, quadrangle lat/long tics catc<br />

Río Caura, quadrangle lat/long numbers caout<br />

Río Caura, quadrangle outline caout<br />

Río Caura, place name annotation caanno5<br />

Río Caura, city points caanno5<br />

Río Caura, province boundary capl<br />

Río Caura, stream annotation cast<br />

Río Caura, streams cast<br />

Río Caura, linear features annotation caft<br />

Río Caura, linear features caft<br />

Río Caura, correlation <strong>of</strong> map units annotation cacor<br />

Río Caura, correlation <strong>of</strong> map units polygons cacor<br />

Río Caura, map key annotation caleg<br />

Río Caura, map key points calegpt<br />

Río Caura, map key arcs caleg<br />

Río Caura, map key magnetics caleg<br />

Río Caura, map key polygons caleg<br />

Río Caura, scale bar annotation cascale<br />

Río Caura, scale bar cascale<br />

Río Caura, rock unit labels calab<br />

Río Caura, rock unit labels leaders calab<br />

Río Caura, buried magnetic bodies cama<br />

Río Caura, geology arcs cage<br />

Río Caura, geology polygons cage<br />

Puerto Ayacucho 2°x3° quadrangle (Venezuela part) ay.av<br />

Index map, latitude/longitude tics vztc<br />

Index map, annotation index<br />

Index map, lat/long grid only grid<br />

Index map, colored countries, lat/long grid index<br />

Puerto Ayacucho, quadrangle lat/long tics aytc

---

Puerto Ayacucho, quadrangle lat/long numbers ayout<br />

Puerto Ayacucho, quadrangle outline ayout<br />

Puerto Ayacucho, place name annotation ayanno5<br />

Puerto Ayacucho, city points ayanno5<br />

Puerto Ayacucho, roads ayrd<br />

Puerto Ayacucho, province boundary aypl<br />

Puerto Ayacucho, streams annotation ayst<br />

Puerto Ayacucho, streams ayst<br />

Puerto Ayacucho, linear features ayft<br />

Puerto Ayacucho, correlation <strong>of</strong> map units annotation aycor<br />

Puerto Ayacucho, correlation <strong>of</strong> map units polygons aycor<br />

Puerto Ayacucho, map key annotation ayleg<br />

Puerto Ayacucho, map key points aylegpt<br />

Puerto Ayacucho, map key arcs ayleg<br />

Puerto Ayacucho, map key magnetics ayleg<br />

Puerto Ayacucho, map key polygons ayleg<br />

Puerto Ayacucho, scale bar annotation ayscale<br />

Puerto Ayacucho, scale bar ayscale<br />

Puerto Ayacucho, rock unit labels aylab<br />

Puerto Ayacucho, rock unit labels leaders aylab<br />

Puerto Ayacucho, section line annotation aylabcr<br />

Puerto Ayacucho, section line on map aylabcr<br />

Puerto Ayacucho, section annotation aycrm<br />

Puerto Ayacucho, section leaders aycrm<br />

Puerto Ayacucho, section geology arcs aycrm<br />

Puerto Ayacucho, section geology polygons aycrm<br />

Puerto Ayacucho, buried mag annotation aymalab<br />

Puerto Ayacucho, buried mag leaders aymalab<br />

Puerto Ayacucho, buried magnetic bodies ayma<br />

Puerto Ayacucho, geology arcs ayge<br />

Puerto Ayacucho, geology polygons ayge<br />

La Esmeralda 2°x3° quadrangle (Venezuela part) es.av<br />

Index map, latitude/longitude tics vztc<br />

Index map, annotation index<br />

Index map, lat/long grid only grid<br />

Index map, colored countries, lat/long grid index<br />

La Esmeralda, quadrangle lat/long numbers esout<br />

La Esmeralda, quadrangle outline esout<br />

La Esmeralda, place name annotation esanno5<br />

La Esmeralda, city points esanno5<br />

La Esmeralda, province boundary espl<br />

La Esmeralda, streams annotation esst<br />

La Esmeralda, streams esst<br />

La Esmeralda, linear features esft<br />

La Esmeralda, structural trends from SLAR essr<br />

La Esmeralda, correlation <strong>of</strong> map units annotation escor<br />

La Esmeralda, correlation <strong>of</strong> map units polygons escor<br />

La Esmeralda, map key annotation esleg<br />

La Esmeralda, map key points eslegpt<br />

La Esmeralda, map key arcs esleg<br />

La Esmeralda, map key polygons esleg

---

La Esmeralda, rock unit labels eslab<br />

La Esmeralda, rock unit labels leaders eslab<br />

La Esmeralda, buried magnetic bodies esma<br />

La Esmeralda, geology arcs esge<br />

La Esmeralda, geology polygons esge<br />

Atabapo 2°x3° quadrangle (Venezuela part) at.av<br />

Index map, latitude/longitude tics vztc<br />

Index map, annotation index<br />

Index map, lat/long grid only grid<br />

Index map, colored countries, lat/long grid index<br />

Atabapo, quadrangle lat/long numbers atout<br />

Atabapo, quadrangle outline atout<br />

Atabapo, place name annotation atanno5<br />

Atabapo, swamp symbols atanno5<br />

Atabapo, province boundary atpl<br />

Atabapo, streams annotation atst<br />

Atabapo, streams atst<br />

Atabapo, linear features atft<br />

Atabapo, correlation <strong>of</strong> map units annotation atcor<br />

Atabapo, correlation <strong>of</strong> map units polygons atcor<br />

Atabapo, map key annotation atleg<br />

Atabapo, map key arcs atleg<br />

Atabapo, map key magnetics atleg<br />

Atabapo, map key polygons atleg<br />

Atabapo, scale bar annotation atscale<br />

Atabapo, scale bar atscale<br />

Atabapo, rock unit labels atlab<br />

Atabapo, rock unit labels leaders atlab<br />

Atabapo, buried magnetic bodies atma<br />

Atabapo, geology arcs atge<br />

Atabapo, geology polygons atge<br />

Río Mavaca 2°x3° quadrangle (Venezuela part) ma.av<br />

Index map, latitude/longitude tics vztc<br />

Index map, annotation index<br />

Index map, lat/long grid only grid<br />

Index map, colored countries, lat/long grid index<br />

Río Mavaca, quadrangle lat/long numbers maout<br />

Río Mavaca, quadrangle outline maout<br />

Río Mavaca, place name annotation maanno5<br />

Río Mavaca, city points maanno5<br />

Río Mavaca, streams annotation mast<br />

Río Mavaca, streams mast<br />

Río Mavaca, linear features maft<br />

Río Mavaca, correlation <strong>of</strong> map units annotation macor<br />

Río Mavaca, correlation <strong>of</strong> map units polygons macor<br />

Río Mavaca, map key annotation maleg<br />

Río Mavaca, map key arcs maleg<br />

Río Mavaca, map key magnetics maleg

---

Río Mavaca, map key polygons maleg<br />

Río Mavaca, scale bar annotation mascale<br />

Río Mavaca, scale bar mascale<br />

Río Mavaca, rock unit labels malab<br />

Río Mavaca, rock unit labels leaders malab<br />

Río Mavaca, geology arcs mage<br />

Río Mavaca, buried magnetic bodies mama<br />

Río Mavaca, geology polygons mage<br />

Piedra de Cocuy 2°x3° quadrangle (Venezuela part) pc.av<br />

Index map, latitude/longitude tics vztc<br />

Index map, annotation index<br />

Index map, lat/long grid only grid<br />

Index map, colored countries, lat/long grid index<br />

Piedra de Cocuy, quadrangle lat/long numbers pcout<br />

Piedra de Cocuy, quadrangle outline pcout<br />

Piedra de Cocuy, place name annotation pcanno5<br />

Piedra de Cocuy, city points pcanno5<br />

Piedra de Cocuy, province boundary pcpl<br />

Piedra de Cocuy, streams annotation pcst<br />

Piedra de Cocuy, streams pcst<br />

Piedra de Cocuy, linear features pcft<br />

Piedra de Cocuy, structural trends from SLAR pcsr<br />

Piedra de Cocuy, correlation <strong>of</strong> map units annotation pccor<br />

Piedra de Cocuy, correlation <strong>of</strong> map units polygons pccor<br />

Piedra de Cocuy, map key annotation pcleg<br />

Piedra de Cocuy, map key points pclegpt<br />

Piedra de Cocuy, map key arcs pcleg<br />

Piedra de Cocuy, map key magnetics pcleg<br />

Piedra de Cocuy, map key polygons pcleg<br />

Piedra de Cocuy, scale bar annotation pcscale<br />

Piedra de Cocuy, scale bar pcscale<br />

Piedra de Cocuy, rock unit labels pclab<br />

Piedra de Cocuy, rock unit labels leaders pclab<br />

Piedra de Cocuy, geology arcs pcge<br />

Piedra de Cocuy, buried magnetic bodies pcma<br />

Piedra de Cocuy, geology polygons pcge

---

ARCVIEW 3 FILES<br />

The ArcView 1 view for <strong>the</strong> enitre study area, “vz.av”, has been converted to<br />

ArcView 3 format, “vz.apr”. It is in “arcunix7/vz” directory. The coverages are in<br />

ARC/INFO 7 format so are useable on Mac, PC <strong>and</strong> UNIX platforms.<br />

The first time you launch <strong>the</strong> vz.apr project on your computer <strong>the</strong> ArcView<br />

Open Project dialog will ask where <strong>the</strong> first coverage is located. On <strong>the</strong> Macintosh,<br />

Arcview 3 can install <strong>the</strong> paths for all <strong>the</strong> coverages if <strong>the</strong> user locates <strong>the</strong> first<br />

coverage in <strong>the</strong> Open Project dialog. Just navigate to <strong>the</strong> arcunix7/vz/info directory.<br />

On Windows <strong>and</strong> UNIX platforms it is best use a word processor <strong>and</strong> global<br />

substitute <strong>the</strong> correct path in <strong>the</strong> vz.apr file. Search for all lines that have <strong>the</strong> key<br />

word “Path:” <strong>and</strong> replace <strong>the</strong> long UNIX path with your path. For instance:<br />

/home10b/resdgs2/pschruben/arc/vz2/cd/arcview.dat/unix<br />

change to:<br />

d:/arcunix7<br />

Yes, ArcView likes forward slashes in <strong>the</strong> project file.

---

GEOLOGY POLYGON ATTRIBUTES:<br />

COVERAGE DATA DEFINITION<br />

The ARC/INFO VZGE.PAT file consists <strong>of</strong>:<br />

COLUMN ITEM NAME WIDTH OUTPUT TYPE INDEXED?<br />

1 AREA 4 12 F<br />

5 PERIMETER 4 12 F<br />

9 VZGE# 4 5 B<br />

13 VZGE-ID 4 5 B<br />

17 FMATN 6 6 C upper-case rock-unit code<br />

23 PTYPEI 3 3 C for sorting units into groups<br />

26 LC 6 6 C mixed-case rock-unit code<br />

32 DESC 60 60 C<br />

92 PTYPES 69 69 C<br />

PTYPEI is a two-digit integer that is used to sort <strong>the</strong> units into groups <strong>of</strong> related<br />

rocks. The third character in PTYPEI is a space for appearance in <strong>the</strong> legend. PTYPES<br />

is composed <strong>of</strong> PTYPEI, PTYPE, <strong>and</strong> DESC. It also can be used to sort correctly by<br />

unit group. All <strong>the</strong> short rock descriptions are in <strong>the</strong> INFO file DESC in alphabetical<br />

order (abbreviations: Fm, Formation; gr, grained; Gp Group; E, Early; Prot,<br />

Proterozoic; rx, rocks; Plio, Pliocene; qtz, quartz; Sg, Supergroup; congl, conglomerate;<br />

qtzite, quartzite; Mid, Middle; terr, terrane; seds, sedimentary rocks; metaseds,<br />

metasedimentary rocks):<br />

LC DESC<br />

blank Unmapped area<br />

d Diabase - mafic dikes undivided (Mesozoic to M Proterozoic)<br />

dioritFenitized diorite & tonalite at Cerro Impacto<br />

ic Carbonatite(?) intrusion <strong>of</strong> Cerro Impacto<br />

Qal Alluvial deposits <strong>of</strong> s<strong>and</strong>, gravel, <strong>and</strong> silt (Quaternary)<br />

QTm Mesa Fm. siltstone <strong>and</strong> s<strong>and</strong>y siltstone (Pleistocene & Plio)<br />

water<br />

Xa Amphibolite schist containing <strong>and</strong>esine (E Prot)<br />

XAgr Granitic rx <strong>of</strong> Imataca Complex (E Prot <strong>and</strong>/or Archean)<br />

XAi Imataca Complex orthogneiss <strong>and</strong> paragneiss (Archean)<br />

XAm Migmatite & gneiss <strong>of</strong> Imataca Complex (E Prot or Archean)<br />

Xbc Basement complex granite to granodiorite gneiss (E Prot)<br />

Xcb Caballape Fm felsic metatuff <strong>and</strong> phyllite (E Prot)<br />

Xcc Cicapra Fm (Carichapo Gp) mafic to intermed metatuff E Prot<br />

Xce El Callao Fm (Carichapo Gp) greenstone, greenschist (E Prot<br />

Xcg Granitic rocks <strong>of</strong> Cuchivero Group (Early Proterozoic)<br />

Xco Cinaruco Fm qtzite, sericitic qtzite, schist (E Prot)<br />

Xcv Caicara Fm (Cuchivero Gp) rhyodacitic-rhyolitic tuff E Prot<br />

Xf1 Felsic metatuff <strong>and</strong> flows (Early Proterozoic)<br />

Xf2 Felsic metatuff <strong>and</strong> flows, eugeosynclinal terrane (E Prot)<br />

Xg Calc-alkaline granite & o<strong>the</strong>r silicic plutonic rx (E Prot)<br />

Xg1 Metagabbro (greenstone belts) (Early Proterozoic)<br />

Xg2 Metagabbro (eugeosynclinal terrane) (Early Proterozoic)<br />

Xgr Granitic rocks, mostly quartz monzonite (Early Proterozoic)

---

Xgu Granitic silicic to intermediate intrusive rocks (E Prot)<br />

Xlc Los Caribes Fm arkose, polymict congl, phyllite (E Prot)<br />

Xm1 Meta-mafic to intermediate flow <strong>and</strong> pyroclastic rx (E Prot)<br />

Xm2 Mafic to intermediate metalava <strong>and</strong> metatuff (E Proterozoic<br />

Xma Maracapra Fm red beds, felsic volcanics (E Proterozoic)<br />

Xmo Moriche Fm metasedimentary conglomerates (E Prot)<br />

Xmp Intrusive rx <strong>of</strong> San Carlos metamorphic-plut terrane (E Prot<br />

Xmu Greenstone belt rocks, undivided (Early Proterozoic)<br />

Xpr Pre-Roraima Gp sedimentary rx clay-rich s<strong>and</strong>stone (E Prot)<br />

Xs1 Schist, phyllite, metatuffs, <strong>and</strong> metavolcanic rx (E Prot)<br />

Xs2 Muscovite schist <strong>and</strong> phyllite, eugeosynclinal terr (E Prot)<br />

Xsm Seds <strong>and</strong> metaseds <strong>of</strong> uncertain affinity qtz arenite (E Prot<br />

Xsp Supamo Complex sodic granitic rx, paragneiss, etc. (E Prot)<br />

Xu1 Metaperidotite, metapyroxenite, serp & talc schist (E Prot)<br />

Xu2 Ultramafic rx metaperidotite, metapyroxenite, etc. (E Prot)<br />

Xui Ultramafic intrusive rx in La Flor-Carapo area (E Prot)<br />

Xyf Yuruari Fm (Pastora Sg) felsic metatuff (E Prot)<br />

Xys Yuruari Fm Pastora Sg qtz muscovite schist, phyllite E Prot<br />

Ylg Late granite intrusive in, <strong>and</strong> doming Roraima seds (M Prot)<br />

Yp Parguaza granite, massive, porphryitic & biotite (M Prot)<br />

YXac Alkaline intrusive complexes (Middle to Early Proterozoic)<br />

YXr Roraima Group (undivided) qtz arenite, arkose M &/or E Prot<br />

YXra Auyantepuy Fm (Roraima Gp) quartz arenite, arkose M, E Prot<br />

YXrc Canaima Fm (Roraima Gp) qtz arenite, arkose, etc. M, E Prot<br />

YXrg Guaiquinima Fm (Roraima Gp) qtz arenite, arkose M, E Prot<br />

GEOLOGY ARC TYPES:<br />

The VZGE.AAT items are:<br />

COLUMN ITEM NAME WIDTH OUTPUT TYPE<br />

1 FNODE# 4 5 B<br />

5 TNODE# 4 5 B<br />

9 LPOLY# 4 5 B<br />

13 RPOLY# 4 5 B<br />

17 LENGTH 4 12 F<br />

21 VZGE# 4 5 B<br />

25 VZGE-ID 4 5 B<br />

29 CODE 3 3 I<br />

32 P1 3 3 I<br />

35 P2 3 3 I<br />

CODE DESC<br />

1 international boundary<br />

2 surface water body<br />

30 geological contact<br />

32 geological contact hidden<br />

FAULT ARCS:<br />

The VZFT.AAT attribute table contains:

---

COLUMN ITEM NAME WIDTH OUTPUT TYPE INDEXED?<br />

1 FNODE# 4 5 B<br />

5 TNODE# 4 5 B<br />

9 LPOLY# 4 5 B<br />

13 RPOLY# 4 5 B<br />

17 LENGTH 4 12 F<br />

21 VZFT# 4 5 B<br />

25 VZFT-ID 4 5 B<br />

29 CODE 3 3 I<br />

32 FTYPEI 3 3 C<br />

35 DESC 60 60 C<br />

95 FTYPES 63 63 C<br />

CODES AND DESCRIPTIONS FOR FAULTS AND OTHER COVERAGES:<br />

The INFO file FTYPE contains:<br />

CODE FTYPEI DESC<br />

20 1 fault<br />

6 2 fault - inferred (dashed)<br />

7 3 fault - implied (dotted)<br />

79 4 thrust fault<br />

127 5 sag fault<br />

17 6 fold axis<br />

21 7 graben<br />

26 8 graben - hidden<br />

25 9 shear zone<br />

72 10 U or Th anomaly<br />

81 11 structural trend<br />

70 12 ring structure<br />

103 13 iron formations<br />

18 14 major magnetic gradient<br />

16 15 fault movement <strong>and</strong> fold arrows<br />

1 16 international boundary<br />

4 17 province boundary<br />

2 18 surface water body<br />

3 18 tributary<br />

5 19 main road<br />

42 20 secondary road<br />

30 21 geological contact<br />

32 22 geological contact hidden<br />

PERMISSIVE TRACT POLYGONS:<br />

The RA.PAT <strong>and</strong> RB.PAT polygon attribute files contain:<br />

COL ITEM NAME WDTH OPUT TYP<br />

1 AREA 4 12 F<br />

5 PERIMETER 4 12 F<br />

9 RA# 4 5 B

---

13 RA-ID 4 5 B<br />

17 FMATN 6 6 C<br />

23 TRACT 5 5 C<br />

28 DESC 64 64 C<br />

92 KEY 69 69 C<br />

TRACT MAP A<br />

KEY<br />

IIa Low-sulfide gold-quartz vein deposits, permissive<br />

IIb Low-sulfide gold-quartz vein deposits, low probability<br />

Ia Algoma iron <strong>and</strong> sedimentary manganese deposits, permissive<br />

Ib Algoma iron <strong>and</strong> sedimentary manganese deposits, low probability<br />

VI Tin greisen deposits<br />

VIII Porphyry copper <strong>and</strong> volcanic-hosted magnetite deposits<br />

TRACT MAP B<br />

KEY<br />

III Kuroko-type massive sulfide deposits<br />

IV Synorogenic-synvolcanic Ni-Cu & related platinum deposits<br />

V Carbonatite deposits <strong>and</strong> diamond-bearing kimberlite pipes<br />

VII Sedimentary kaolin deposits<br />

MINERAL DEPOSIT POINTS:<br />

The original list <strong>of</strong> mineral deposits in Bulletin 2062 (<strong>USGS</strong> <strong>and</strong> Corporación<br />

Venezolana de Guayana, Técnica Minera, C.A., 1993) was not available in digital form<br />

at <strong>the</strong> time <strong>of</strong> publication <strong>of</strong> this CD-ROM. Consequently, a new retrieval was made<br />

from <strong>the</strong> <strong>USGS</strong> Mineral <strong>Resource</strong>s Data System (Schruben, 1986). This also takes<br />

advantage <strong>of</strong> any updates that may have taken place in <strong>the</strong> data base. The retrieval<br />

netted 2353 deposits in Venezuela, Guayana, Surinam, French Guinea, <strong>and</strong> Brazil, <strong>of</strong><br />

which 459 deposits fell in <strong>the</strong> study area. The following fields are present in <strong>the</strong><br />

DEPOSIT.PAT file:<br />

COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME<br />

1 AREA 4 12 F 3<br />

5 PERIMETER 4 12 F 3<br />

9 DEPOSIT# 4 5 B -<br />

13 DEPOSIT-ID 4 5 B -<br />

17 RECNO 7 7 C -<br />

24 SITE 40 40 C -<br />

64 CTRY.CODE 2 2 C -<br />

66 STATE 13 13 C -<br />

79 LATITUDE 9 9 C -<br />

88 LONGITUDE 10 10 C -<br />

98 COMMOD_GP 11 11 C -<br />

109 COMMOD 34 34 C -<br />

143 COMMOD1 4 4 C -

---

147 ORE.MAT 60 60 C -<br />

207 DEP.TYPE 40 40 C -<br />

247 DEP.COMMENTS 80 80 C -<br />

327 MODEL 40 40 C -<br />

367 HOST.RK.NAME 60 60 C -<br />

427 HOST.RK.TYPE 60 60 C -<br />

487 HOST.ROCK.AGE 10 10 C -<br />

497 ASOC.RK.NAME 60 60 C -<br />

557 ASOC.RK.TYPE 60 60 C -<br />

617 ASSOC.ROCK.AGE 10 10 C -<br />

627 ALTERATION 80 80 C -<br />

707 GEOL.COMMENTS 80 80 C -<br />

787 GEN.COMMENTS 80 80 C -<br />

867 REFERENCE 80 80 C -<br />

COMMOD1 is used to assign symbols to <strong>the</strong> sites for plotting. Please note that some<br />

fields are truncated from <strong>the</strong> original MRDS information, particularly <strong>the</strong><br />

REFERENCE field.

---

DLG OPTIONAL FORMAT<br />

The DLG format is a U.S. Geological Survey st<strong>and</strong>ard for storing topologically<br />

structured files. It results in a compact ASCII file that is compatible with a variety <strong>of</strong><br />

graphics s<strong>of</strong>tware.<br />

The <strong>Venezuelan</strong> Guayana Shield geology, faults, <strong>and</strong> correlation chart have<br />

been converted to Digital Line Graph (DLG) Optional format files. The DLG files<br />

contain tagged polygons <strong>and</strong> arcs. Annotation text is not supported in <strong>the</strong> DLG<br />

conversion s<strong>of</strong>tware <strong>and</strong> is not present in <strong>the</strong> DLG files. The DLG file directory<br />

follows:<br />

cor.dlg correlation <strong>of</strong> map units in Equidistant Conic projection<br />

cordd.dlg correlation <strong>of</strong> map units in decimal degrees<br />

ft.dlg faults in Equidistant Conic projection<br />

ftdd.dlg faults in decimal degrees<br />

ge.dlg geology in Equidistant Conic projection<br />

gedd.dlg geology in decimal degrees<br />

ptype.unl rock unit names, descriptions, colors for Versatec plotter<br />

scale.dlg scale bar in Equidistant Conic projection<br />

scaledd.dlg scale bar in decimal degrees<br />

vzline.unl fault <strong>and</strong> contact line types<br />

Although <strong>the</strong> conversion to ARC/INFO is more easily accomplished with<br />

ARC/EXPORT files, which are included elsewhere on this disc, <strong>the</strong> following<br />

instructions for converting DLG files to ARC/INFO may be illustrative for converting<br />

DLG files to non-ARC/INFO platforms.<br />

These methods for converting DLG files to ARC/INFO coverages have been<br />

adapted from ARC/INFO manuals (Environmental Systems Research Institute, 1990):<br />

1) Copy <strong>the</strong> .dlg <strong>and</strong> .unl files from <strong>the</strong> CD-ROM. For instance, from a UNIX prompt,<br />

type:<br />

arc<br />

cw vz create arc/info workspace<br />

q<br />

cd vz<br />

cdrom in<br />

cp /pdd/cdrom/datafiles/dlg/*.unl .<br />

cdrom out<br />

2) Launch ARC/INFO <strong>and</strong> create a lookup table for <strong>the</strong> rock unit codes:<br />

arc<br />

tables<br />

define ptype.lut<br />

Enter Comm<strong>and</strong>: define ptype.lut<br />

1<br />

Item Name: major1<br />

Item Width: 6<br />

Item Output Width: 6<br />

Item Type: i

---

7<br />

Item Name: fmatn<br />

Item Width: 6<br />

Item Output Width: 6<br />

Item Type: c<br />

13<br />

Item Name: ptypei<br />

Item Width: 3<br />

Item Output Width: 3<br />

Item Type: c<br />

16<br />

Item Name: lc<br />

Item Width: 6<br />

Item Output Width: 6<br />

Item Type: c<br />

22<br />

Item Name: color<br />

Item Width: 3<br />

Item Output Width: 3<br />

Item Type: i<br />

25<br />

Item Name: desc<br />

Item Width: 60<br />

Item Output Width: 60<br />

Item Type: c<br />

85<br />

Item Name:<br />

Enter Comm<strong>and</strong>: alter fmatn<br />

COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME<br />

7 FMATN 6 6 C -<br />

Item name:<br />

Item output width:<br />

Item type:<br />

Alternate item name: cross<br />

COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME<br />

7 FMATN 6 6 C - CROSS<br />

Enter Comm<strong>and</strong>: alter color<br />

COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME<br />

22 COLOR 3 3 I -<br />

Item name:<br />

Item output width:<br />

Item type:<br />

Alternate item name: symbol<br />

COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME<br />

22 COLOR 3 3 I - SYMBOL<br />

Enter Comm<strong>and</strong>: get ptype.unl<br />

The geology polygon lookup table should look as follows:<br />

COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME INDEXED?<br />

1 MAJOR1 6 6 I - -<br />

7 FMATN 6 6 C - CROSS -

---

13 PTYPEI 3 3 C - -<br />

16 LC 6 6 C - -<br />

22 COLOR 3 3 I - SYMBOL -<br />

25 DESC 60 60 C - -<br />

Enter Comm<strong>and</strong>: list major1 fmatn ptypei lc color<br />

Record major1 fmatn ptypei lc color<br />

1 1 DEEP deep 0<br />

2 2 BLACK black 1<br />

3 3 POS pos 0<br />

4 4 NEG neg 0<br />

5 5 KIMB Kimb 0<br />

6 6 H2O 1 water 61<br />

7 7 QAL 2 Qal 129<br />

8 8 QTM 3 QTm 4<br />

9 9 YXAC 5 YXac 213<br />

10 10 YLG 6 Ylg 106<br />

11 11 IC 7 ic 72<br />

12 12 YXR 8 YXr 123<br />

13 13 YXRA 9 YXra 123<br />

14 14 YXRG 10 YXrg 123<br />

15 15 YXRC 11 YXrc 123<br />

16 16 XPR 12 Xpr 123<br />

17 17 AC 13 ac 213<br />

18 18 XGU 14 Xgu 188<br />

19 19 XG 15 Xg 247<br />

20 20 XCG 16 Xcg 187<br />

21 21 DIORIT 17 diorit 187<br />

Continue? n<br />

Enter Comm<strong>and</strong>: list desc<br />

Record desc<br />

1<br />

2<br />

3<br />

4<br />

5<br />

6<br />

7 Alluvial deposits <strong>of</strong> s<strong>and</strong>, gravel, <strong>and</strong> silt (Quaternary)<br />

8 Mesa Fm. siltstone <strong>and</strong> s<strong>and</strong>y siltstone (Pleistocene & Plio)<br />

9 Mesa Fm. siltstone <strong>and</strong> s<strong>and</strong>y siltstone (Pleistocene & Plio)<br />

10 Alkaline intrusive complexes (Middle to Early Proterozoic)<br />

11 Intrusive rocks in <strong>and</strong> doming Roraima seds (Mid Prot)<br />

12 Carbonatite intrusion <strong>of</strong> Cerro Impacto<br />

13 Roraima Group (undivided) qtz arenite, arkose M &/or E Prot<br />

14 Auyantepui Fm (Roraima Gp) quartz arenite, arkose M, E Prot<br />

15 Canaima Fm (Roraima Gp) qtz arenite, arkose, etc. M, E Prot<br />

16 Guaiquinima Fm (Roraima Gp) qtz arenite, arkose M, E Prot<br />

17 Pre-Roraima Gp sedimentary rx clay-rich s<strong>and</strong>stone (E Prot)<br />

18 Granitic silicic to intermediate intrusive rocks (E Prot)<br />

19 Calc-alkaline granite & o<strong>the</strong>r silicic plutonic rx (E Prot)<br />

20 Grantitc rocks <strong>of</strong> Cuchivero Group (Early Proterozoic)<br />

21 fenitized diorite & tonalite at Cerro Impacto<br />

Continue? n

---

3) Create a lookup table for <strong>the</strong> faults <strong>and</strong> contacts.<br />

tables<br />

Enter Comm<strong>and</strong>: define vzline.lut<br />

1<br />

Item Name: major1<br />

Item Width: 6<br />

Item Output Width: 6<br />

Item Type: i<br />

7<br />

Item Name: code<br />

Item Width: 3<br />

Item Output Width: 3<br />

Item Type: i<br />

10<br />

Item Name: line<br />

Item Width:<br />

Integer value expected.<br />

Item Width: 3<br />

Item Output Width: 3<br />

Item Type: i<br />

13<br />

Item Name: expl<br />

Item Width: 45<br />

Item Output Width: 45<br />

Item Type: c<br />

58<br />

Item Name:<br />

Enter Comm<strong>and</strong>: alter line<br />

COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME<br />

10 LINE 3 3 I -<br />

Item name:<br />

Item output width:<br />

Item type:<br />

Alternate item name: symbol<br />

COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME<br />

10 LINE 3 3 I - SYMBOL<br />

Enter Comm<strong>and</strong>: it<br />

COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME<br />

INDEXED?<br />

1 MAJOR1 6 6 I - -<br />

7 CODE 3 3 I - -<br />

10 LINE 3 3 I - SYMBOL -<br />

13 EXPL 45 45 C - -<br />

Enter Comm<strong>and</strong>: get vzline.unl<br />

43 Records Selected.

---

Enter Comm<strong>and</strong>: list<br />

Record MAJOR1 CODE LINE EXPL<br />

1 1 0 9 MAP BORDER NEAT LINE<br />

2 2 1 109 INTL BORDER LONG & SHORT DASH<br />

3 3 2 4 SURFACE WATER BODIES<br />

4 4 3 111 NAMED TRIBUTARIES - BLUE<br />

5 5 4 120 PROVINCES (STATE BOUNDARIES) WAS 118<br />

6 6 5 41 MAIN ROADS SOLID/OPEN<br />

7 7 6 106 FAULT - DASHED INFERRED UNDER RX<br />

8 8 7 117 FAULT - DOTTED IMPLIED UNDER H20-Q<br />

9 9 8 112 THRUST TEETH ON LEFT<br />

10 10 9 1 SECTION LINE<br />

11 11 10 1 BOXES; SCALE<br />

12 12 11 33 DIRT ROAD<br />

13 13 15 5 MAG DERIVED FAULT<br />

14 14 16 1 LEADERS ARROWS<br />

15 15 17 1 FOLD AXIS<br />

16 16 18 101 MAJOR MAG GRADIENT - DOT<br />

17 17 19 106 FAULT - HIDDEN. WAS GSMAP 32<br />

18 18 20 5 LINEAMENT; FAULT<br />

19 19 21 85 GRABEN HATCH ON RIGHT SIDE OF LINE<br />

20 20 23 86 GRABEN HATCH ON LEFT SIDE OF LINE<br />

21 21 25 5 SHEAR ZONE<br />

22 22 26 87 GRABEN HIDDEN HATCH ON RIGHT<br />

Continue? n<br />

Enter Comm<strong>and</strong>: q stop<br />

4) The dlgarc comm<strong>and</strong> creates .pcode <strong>and</strong> .acode INFO files which are used to link<br />

<strong>the</strong> .lut tables to <strong>the</strong> coverage. Some <strong>of</strong> this linking may be automatic in non-<br />

ARC/INFO conversions. If not, <strong>the</strong> technique is to use <strong>the</strong> common -id field to join<br />

<strong>the</strong> .acode <strong>and</strong> .pcode files to <strong>the</strong> coverage, <strong>the</strong>n use major1 as <strong>the</strong> common field to<br />

link ptype.lut <strong>and</strong> vzline.lut to <strong>the</strong> coverage.<br />

Choose a dlg file to convert - Equidistant Conic (ge.dlg) or Decimal Degrees<br />

(gedd.dlg). The following example is for <strong>the</strong> Equidistant Conic coverages:<br />

kill ge all<br />

dlgarc optional ../dlg/ge.dlg ge<br />

build ge<br />

build ge line<br />

/* join <strong>the</strong> major1 item from ge.pcode using <strong>the</strong> -id as key<br />

joinitem ge.pat ge.pcode ge.pat ge-id ge-id<br />

/* join <strong>the</strong> unit names, colors <strong>and</strong> description from ptype.lut using major1<br />

joinitem ge.pat ptype.lut ge.pat major1 major1<br />

/* join major1 which contains <strong>the</strong> line type from ge.acode<br />

joinitem ge.aat ge.acode ge.aat ge-id ge-id

---

* join major1 which contains <strong>the</strong> contact line type from ge.acode<br />

joinitem ge.aat vzline.lut ge.aat major1 major1<br />

kill ft all<br />

dlgarc optional ../dlg/ft.dlg ft<br />

build ft line<br />

/* join <strong>the</strong> major1 item from ft.acode using <strong>the</strong> -id as key<br />

joinitem ft.aat ft.acode ft.aat ft-id ft-id<br />

/* join major1 which contains <strong>the</strong> fault line type from ft.acode<br />

joinitem ft.aat vzline.lut ft.aat major1 major1<br />

kill cor all<br />

dlgarc optional ../dlg/cor.dlg cor<br />

build cor<br />

build cor line<br />

/* join <strong>the</strong> major1 item from cor.pcode using <strong>the</strong> -id as key<br />

joinitem cor.pat cor.pcode cor.pat cor-id cor-id<br />

/* join <strong>the</strong> unit names, colors <strong>and</strong> description from ptype.lut using major1<br />

joinitem cor.pat ptype.lut cor.pat major1 major1<br />

/* join major1 which contains <strong>the</strong> line type from cor.acode<br />

joinitem cor.aat cor.acode cor.aat cor-id cor-id<br />

/* join major1 which contains <strong>the</strong> contact line type from cor.acode<br />

joinitem cor.aat vzline.lut cor.aat major1 major1<br />

kill scale all<br />

dlgarc optional ../dlg/scale.dlg scale<br />

build scale line<br />

/* join <strong>the</strong> major1 item from scale.acode using <strong>the</strong> -id as key<br />

joinitem scale.aat scale.acode scale.aat scale-id scale-id<br />

/* join major1 which contains <strong>the</strong> fault line type from scale.acode<br />

joinitem scale.aat vzline.lut scale.aat major1 major1

---

DESCRIPTION OF MAP UNITS<br />

SEDIMENTARY ROCKS<br />

Qal - Alluvial deposits (Quaternary)—-S<strong>and</strong>, gravel, <strong>and</strong> silt<br />

QTm - Mesa Formation (Pleistocene <strong>and</strong> Pliocene)--Siltstone <strong>and</strong> s<strong>and</strong>y<br />

siltstone, generally reddish; massive to laminated. Unconsolidated<br />

gravel <strong>and</strong> s<strong>and</strong> in upper part. Called Tm on some earlier maps<br />

YXr - Roraima Group (Middle <strong>and</strong> (or) Early Proterozoic), undivided—<br />

Compilation <strong>of</strong> regional ages indicates an age <strong>of</strong> 1,900–1,500 Ma (Sidder<br />

<strong>and</strong> Mendoza-S., 1991)<br />

YXra - Auyantepuy Formation—-Mainly quartz arenite <strong>and</strong> minor arkose;<br />

forms steep cliffs <strong>and</strong> flat-topped mesas. Thickness 300–700 m.<br />

Equivalent to Matauí Formation <strong>of</strong> Reid <strong>and</strong> Bisque (1975)<br />

YXrg - Guaiquinima Formation—-Fine-grained quartz arenite <strong>and</strong> arkose that<br />

are cross stratified; red, green, <strong>and</strong> greenish-gray jasper<br />

composed <strong>of</strong> devitrified <strong>and</strong> silicified ash <strong>and</strong> small crystals <strong>of</strong><br />

quartz <strong>and</strong> feldspar. Wea<strong>the</strong>rs to form flat or gently sloping<br />

topography. Upper part is mostly covered with debris from<br />

overlying Auyantepuy Formation. Several hundreds <strong>of</strong> meters thick.<br />

Equivalent to all but <strong>the</strong> lowermost part <strong>of</strong> <strong>the</strong> Uaimapué<br />

Formation <strong>of</strong> Reid <strong>and</strong> Bisque (1975)<br />

YXrc - Canaima Formation—-Quartz arenite, arkose, conglomeratic arenite,<br />

conglomerate, siltstone, <strong>and</strong> shale. Abundant crossbeds in<br />

arenite <strong>and</strong> arkose units. Wea<strong>the</strong>rs to form cliffs on resistant<br />

arenite, arkose, <strong>and</strong> conglomerate units <strong>and</strong> slopes on relatively<br />

nonresistant siltstone, shale, <strong>and</strong> silty arenite units. About<br />

1,000–2,000 m thick. Equivalent to Uairén <strong>and</strong> Kukuenán<br />

Formations <strong>and</strong> lowermost part <strong>of</strong> Uaimapué Formation <strong>of</strong> Reid <strong>and</strong><br />

Bisque (1975)<br />

Xpr - Pre-Roraima Group sedimentary rocks (Early Proterozoic)—-Fine-grained<br />

to very fine grained, clay-rich s<strong>and</strong>stone, locally containing granulesize<br />

quartz grains. Interbedded with red shale <strong>and</strong> s<strong>and</strong>y shale<br />

(Briceño, 1982)<br />

Xco - Cinaruco Formation (Early Proterozoic)--Quartzite <strong>and</strong> sericitic<br />

quartzite <strong>and</strong> minor amounts <strong>of</strong> sericite-quartz schist <strong>and</strong> phyllite,<br />

ferruginous quartzite, <strong>and</strong> one or more intra-formational quartzite<br />

conglomerates (McC<strong>and</strong>less, 1962)<br />

Xlc - Los Caribes Formation (Early Proterozoic)--Weakly metamorphosed<br />

sequence <strong>of</strong> reddish arkose, polymict conglomerate, <strong>and</strong> finely laminated<br />

phyllite with minor felsic tuff<br />

Xma - Maracapra Formation (Early Proterozoic)--Weakly metamorphosed red<br />

beds <strong>and</strong> felsic volcanic rocks<br />

EUGEOSYNCLINAL TERRANE<br />

Xm2 - Mafic to intermediate metalava <strong>and</strong> metatuff (Early Proterozoic)--<br />

Chlorite+epidote±actinolite schist <strong>and</strong> semischist, <strong>and</strong> greenstone,<br />

commonly with relict pyroxene phenocrysts. Relict textures suggest that<br />

protoliths were amygdaloidal flows <strong>and</strong> lithic- <strong>and</strong> crystal-rich tuffs

---

Xf2 - Felsic metatuff <strong>and</strong> flows (Early Proterozoic)--Quartz+muscovite±<br />

chloritoid semischist with relict phenocrysts <strong>of</strong> partially resorbed<br />

quartz <strong>and</strong> broken plagioclase replaced by albite. Groundmass mainly<br />

devitrified glass. Traces <strong>of</strong> relict lapilli locally abundant<br />

Xs2 - Muscovite schist <strong>and</strong> phyllite (Early Proterozoic)--Quartz+muscovite±<br />

chlorite±chloritoid±ankerite schist <strong>and</strong> phyllite, <strong>and</strong> subordinate<br />

quartzite or metachert derived from sedimentary <strong>and</strong> felsic volcanic<br />

rocks. Ankeritic rocks wea<strong>the</strong>r to ferruginous schist <strong>and</strong> phyllite<br />

Xg2 - Metagabbro (Early Proterozoic)<br />

MAFIC AND ULTRAMAFIC ROCKS OF<br />

THE EUGEOSYNCLINAL TERRANE<br />

Xu2 - Ultramafic rocks (Early Proterozoic)--Mainly metaperidotite <strong>and</strong><br />

metapyroxenite, serpentinite, <strong>and</strong> talc schist. Cumulus texture locally<br />

preserved<br />

VOLCANIC ROCKS<br />

Xcv - Caicara Formation <strong>of</strong> <strong>the</strong> Cuchivero Group (Early Proterozoic)--<br />

Unmetamorphosed ash-flow tuffs <strong>and</strong> rhyolitic to dacitic flows <strong>and</strong><br />

breccias. A U-Pb age <strong>of</strong> 1,980 Ma was obtained from ash-flow tuff near<br />

Icabarú (Brooks <strong>and</strong> o<strong>the</strong>rs, in press). Called Xc on some maps<br />

INTRUSIVE ROCKS<br />

d - Diabase (Mesozoic to Early Proterozoic)--Dark-gray to greenish-gray,<br />

fine- to coarse-grained diabase <strong>of</strong> tholeiitic composition. Forms dikes<br />

<strong>and</strong> sills. K-Ar ages <strong>of</strong> diabase in region are 210–200 Ma <strong>and</strong> 1,700–<br />

1,600± 0.8 Ma (Teggin <strong>and</strong> o<strong>the</strong>rs, 1985; Sidder <strong>and</strong> Mendoza, 1991).<br />

In cases where locations were determined from side looking airborne radar<br />

(SLAR) interpretation or from aeromagnetic data, <strong>the</strong> map symbol is<br />

crosshatched<br />

Yp - Parguaza Granite (Middle Proterozoic)--Massive, coarsely crystalline,<br />

porphyritic granite <strong>and</strong> biotite granite commonly with rapakivi texture<br />

These rocks have been dated about 1,545 Ma, (zircon age; 1,531±39Ma<br />

(Rb/Sr age) Gaudette <strong>and</strong> o<strong>the</strong>rs, 1978). The Parguaza Granite is<br />

reported by Mendoza <strong>and</strong> o<strong>the</strong>rs (1977) <strong>and</strong> Ghosh (1985) to be<br />

unconformably overlain by <strong>the</strong> Roraima Group, although isotopic dates on<br />

<strong>the</strong> Parguaza Granite (about 1,545 Ma) are within <strong>the</strong> possible age span<br />

<strong>of</strong> <strong>the</strong> Roraima Group (1,900 to 1,545 Ma)(Ghosh, 1985; Sidder <strong>and</strong><br />

Mendoza-S., 1991). These age relations can be explained if <strong>the</strong> Roraima<br />

Group varies significantly in age within <strong>the</strong> Guayana Shield; that is,<br />

<strong>the</strong> Roraima Group may be relatively young (

---

1°10' N., long 66°50' W.), a similar body named <strong>the</strong> Piedra de Cocuy was<br />

described as a granodiorite with 20 percent biotite, 30 percent quartz,<br />

40 percent feldspar, <strong>and</strong> 10 percent hornblende (Marcano <strong>and</strong> o<strong>the</strong>rs,<br />

written communication, 1991). These rocks are characterized by small,<br />

subrounded, <strong>and</strong> generally strong magnetic anomalies <strong>and</strong> are commonly<br />

visible in SLAR imagery<br />

ic - Carbonatite intrusion <strong>of</strong> Cerro Impacto (Mesozoic to Early<br />

Proterozoic)--Inferred primarily from geochemistry <strong>of</strong> <strong>the</strong> laterite (which<br />

is enriched in Ta, Nb, Th, Ba, <strong>and</strong> rare earth elements (REE)) <strong>and</strong> barite<br />

outcrops <strong>and</strong> from geophysical interpretation that indicates a magnetiterich<br />

core. Carbonatite underlies a north-trending ridge that has a thick<br />

lateritic cover in a depression composed <strong>of</strong> fenitized granodiorite <strong>and</strong><br />

tonalite. Age may be as young as 80 Ma (Mendoza <strong>and</strong> o<strong>the</strong>rs, 1977) or as<br />

old as 1,800 Ma as inferred from intrusive relationship with <strong>the</strong> granitic<br />

rocks <strong>of</strong> <strong>the</strong> Cuchivero Group (1,900–1,800 Ma; Sidder <strong>and</strong> Mendoza-S.,<br />

1991)<br />

YXac - Alkaline complexes (Middle <strong>and</strong> Early Proterozoic). Generally<br />

small <strong>and</strong> rounded to subrounded. The structure 2.5 km in diameter at<br />

La Churuata (3 o 20'N, 65 o 25'W) intruded <strong>the</strong> base <strong>of</strong> <strong>the</strong> eastern flank<br />

<strong>of</strong> Cerro Duida, sou<strong>the</strong>ast <strong>of</strong> Cerro Marahuaca, <strong>and</strong> has a Rb/Sr date <strong>of</strong><br />

1,300 Ma (Soares, 1985). Its composition has been described as a<br />

combination <strong>of</strong> "saturated syenites, quartz-syenites, nepheline<br />

syenites, <strong>and</strong> granites", <strong>the</strong> latter apparently deriving from<br />

assimilation <strong>of</strong> <strong>the</strong> s<strong>and</strong>stones from <strong>the</strong> surrounding Roraima<br />

Formation. Aegirine, riebeckite, biotite, zircon, monazite, <strong>and</strong><br />

bastnaesite have been identified. This structure has associated U,<br />

Th, REE, Zr, <strong>and</strong> Sn geochemical anomalies. Ano<strong>the</strong>r example in <strong>the</strong><br />

nor<strong>the</strong>astern corner <strong>of</strong> La Esmeralda quadrangle (3 o 50'N, 63 o 10'W), is<br />

coarsely crystalline, (phenocrysts from 1 to 2.5 cm), alkalic, with<br />

apparent flow-b<strong>and</strong>ing <strong>of</strong> <strong>the</strong> feldspar crystals (Jeff Wynn, U.S.<br />

Geological Survey, written communication, 1991). These rocks are<br />

generally only very weakly magnetic, yet are <strong>of</strong>ten visible in <strong>the</strong><br />

SLAR imagery.. The examples in Caura quadrangle are inferred to be<br />

similar based on interpretation <strong>of</strong> aeromagnetic data. Called ac on some<br />

maps<br />

Xg - Calc-alkaline granite <strong>and</strong> o<strong>the</strong>r silicic plutonic rocks (Early<br />

Proterozoic)--Martínez (1991) described <strong>the</strong>se rocks as massive, coarsegrained,<br />

gray, equigranular biotite granites with rapakivi texture<br />

similar to <strong>the</strong> Parguaza batholith. These granites are seen west <strong>and</strong><br />

north <strong>of</strong> Cerro Duida (lat 4°00' N., long 65°30' W.) in <strong>the</strong> Amazonas<br />

Federal Territory. These rocks are weakly to moderately magnetic,<br />

commmonly with east-west to west-northwest trends in <strong>the</strong> magnetic<br />

anomalies. Pronounced west-northwest-striking lineaments in <strong>the</strong> SLAR<br />

imagery are characteristic, especially in <strong>the</strong> Atabapo quadrangle.<br />

XAgr - Granitic rocks intruding <strong>the</strong> Imataca Complex (Early Proterozoic <strong>and</strong><br />

(or) Archean)--Mostly quartz monzonite. Age uncertain; may include<br />

granitoids as old as Late Archean as well as granitoids <strong>of</strong> Early<br />

Proterozoic age equivalent to <strong>the</strong> Supamo or Cuchivero Groups<br />

XAm - Migmatite <strong>and</strong> gneiss associated with <strong>the</strong> Imataca Complex (Early<br />

Proterozoic <strong>and</strong> (or) Archean)--Quartz monzonite, migmatite, <strong>and</strong> lineated<br />

gneiss<br />

Xcg - Granitic rocks <strong>of</strong> <strong>the</strong> Cuchivero Group (Early Proterozoic)--Includes

---

granites <strong>of</strong> Guaniamito, San Pedro, <strong>and</strong> Santa Rosalía intruded into<br />

volcanic rocks <strong>of</strong> <strong>the</strong> Caicara Formation. Commonly equigranular to<br />

porphyritic, medium to coarse grained, <strong>and</strong> locally foliated.<br />

Phenocrysts include orthoclase, microcline, plagioclase, quartz,<br />

biotite, muscovite, <strong>and</strong> accessory sphene, apatite, zircon, <strong>and</strong><br />

hornblende. Rb-Sr isotopic age range <strong>of</strong> 1,900 to 1,800 Ma (Sidder <strong>and</strong><br />

Mendoza-S., 1991)<br />

diorit - Fenitized zone in Xcg at Cerro Impacto—-Caused by <strong>the</strong> underlying<br />

carbonatite. Indicated by smooth depression on SLAR imagery<br />

Xgu - Intrusive rocks, undivided (Early Proterozoic)--Underlying waterinundated<br />

plains <strong>and</strong> jungle in <strong>the</strong> sou<strong>the</strong>astern Amazonas Federal<br />

Territory. Where seen south <strong>and</strong> east <strong>of</strong> San Fern<strong>and</strong>o de Atabapo (lat<br />

3°45' N., long 67°40' W.), <strong>the</strong>y are described as biotite hornblende<br />

granites <strong>and</strong> granite gneisses (Marcano <strong>and</strong> o<strong>the</strong>rs, 1991). These rocks<br />

are weakly magnetic <strong>and</strong> have no apparent trend<br />

Xgr - Granitic rocks (Early Proterozoic)--Mostly quartz monzonite.<br />

Porphyritic, medium to coarse grained, some inclusions <strong>of</strong> granodiorite.<br />

May include potassic granitoids as old as <strong>the</strong> Supamo Complex <strong>and</strong> (or)<br />

granitoids as young as or younger than <strong>the</strong> Cuchivero Group<br />

Xsp - Supamo Complex (Early Proterozoic)--Sodic granitic rocks, paragneiss,<br />

migmatite, granodiorite, <strong>and</strong> sparse pegmatite. About 2,230 to 2,050 Ma<br />

(Sidder <strong>and</strong> Mendoza-S., 1991)<br />

GREENSTONE BELT ROCKS OF THE<br />

GUASIPATI-EL CALLAO AREAS<br />

Xcb - Caballape Formation (Early Proterozoic)--Mainly felsic metatuff <strong>and</strong><br />

phyllite derived from laminated volcaniclastic siltstone <strong>and</strong> graywacke.<br />

Metatuff contains plagioclase phenocrysts, resorbed phenocrysts <strong>of</strong><br />

quartz, wisps <strong>of</strong> pumice, <strong>and</strong> minor lithic clasts<br />

Pastora Supergroup (Early Proterozoic)--Divided into:<br />

Yuruari Formation<br />

Xyf - Felsic metatuff--Quartz±muscovite±calcite semischist. Contains relict<br />

quartz <strong>and</strong> feldspar phenocrysts <strong>and</strong> traces <strong>of</strong> lapilli <strong>and</strong> breccia<br />

clasts. Minor greenstone<br />

Xys - Muscovite schist <strong>and</strong> phyllite--Finely laminated quartz+muscovite±<br />

chloritoid±biotite±<strong>and</strong>alusite±sillimanite schist. Locally contains<br />

volcaniclastic metas<strong>and</strong>stone <strong>and</strong> felsic metatuff <strong>and</strong> breccia<br />

Carichapo Group<br />

Xcc - Cicapra Formation--Mafic to intermediate metatuff. Mainly albite+<br />

epidote±biotite amphibolite. Relict textures suggest interlayering <strong>of</strong><br />

tuff <strong>and</strong> volcaniclastic s<strong>and</strong>stone<br />

Xce - El Callao Formation--Greenstone, greenschist <strong>and</strong> minor talc schist<br />

<strong>and</strong> amphibolite. Relict pillow structure is common. Flows are commonly<br />

intercalated with flow breccias. Fine-grained quartz-hematite rocks in

---

uppermost part. Minor chert<br />

GREENSTONE BELT ROCKS ELSEWHERE IN THE GUAYANA SHIELD<br />

Xsm - Sedimentary <strong>and</strong> metasedimentary rocks (Early Proterozoic)--Rocks <strong>of</strong><br />

uncertain affinity along or near Río Oris in sou<strong>the</strong>astern Ciudad Piar<br />

quadrangle. Corresponds in part to La Quina Formation <strong>of</strong> Bellizzia-G.<br />

<strong>and</strong> o<strong>the</strong>rs (1976). Hematitic quartz arenite; reddish phyllitic<br />

siltstone; feldspathic arenite; conglomeratic arenite; quartz-sericite<br />

phyllite; red, laminated, fine-grained meta-arenite with graded bedding<br />

<strong>and</strong> erosional channels<br />

Xma - Maracapra Formation <strong>of</strong> Bellizzia-G. <strong>and</strong> o<strong>the</strong>rs (1976) (Early<br />

Proterozoic)--Weakly metamorphosed red beds <strong>and</strong> felsic volcanic rocks<br />

Xmu - Greenstone belt rocks, undivided (Early Proterozoic)--Gold-bearing,<br />

greenstone belt rocks are reported in <strong>the</strong> upper Río Orinoco headwaters,<br />

La Esmeralda quadrangle. The tremendous magnetic gradients in this area<br />

tend to be sinuous <strong>and</strong> linear. They resemble gradients <strong>of</strong> <strong>the</strong> greenstone<br />

belt rocks in eastern Bolívar State. This terrane is distinguished by low<br />

to moderate relief in <strong>the</strong> SLAR imagery<br />

Xa - Amphibolite schist (Early Proterozoic)--Includes local coarse-grained<br />

metagabbro<br />

Xf1 - Felsic metatuff <strong>and</strong> flows (Early Proterozoic)--<br />

Quartz+muscovite±chlorite semischist with relict phenocrysts <strong>of</strong><br />

partially resorbed quartz <strong>and</strong> broken feldspar<br />

Xm1 - Mafic to intermediate metalava <strong>and</strong> metatuff (Early Proterozoic)--<br />

Chlorite+albite+epidote±actinolite schist, semischist, <strong>and</strong> greenstone,<br />

locally amygdaloidal. Subordinate hornblende hornfels, albite-epidote<br />

amphibolite <strong>and</strong> minor amphibolite. Minor chert<br />

Xs1 - Schist, phyllite, metatuff, <strong>and</strong> metavolcanic rocks (Early<br />

Proterozoic)--Quartz-mica schist; quartz-sericite-chlorite schist;<br />

sericitic meta-arenite; sericitic-chloritic phyllite; rhyolitic,<br />

dacitic, <strong>and</strong>esitic, <strong>and</strong> basaltic metatuffs; minor metabasalt <strong>and</strong> meta<strong>and</strong>esite<br />

Xg1 - Metagabbro (Early Proterozoic)--Saussuritized <strong>and</strong>, locally,<br />

amphibolitized metagabbro. Cumulus texture locally preserved<br />

Xu1 - Ultramafic rocks (Early Proterozoic)--Mainly metaperidotite <strong>and</strong><br />

metapyroxenite, serpentinite, <strong>and</strong> talc schist<br />

Xui - Ultramafic intrusive rocks in La Flor-Carapo area (Early<br />

Proterozoic)--Medium- to coarse-grained pyroxenite sills; ophitic or<br />

subophitic to cumulate textures; saussuritized plagioclase,<br />

clinopyroxene altered to green hornblende, <strong>and</strong> sparse olivine

---

ROCKS OF THE IMATACA PROVINCE<br />

XAi - Imataca Complex (Early Proterozoic <strong>and</strong> (or) Archean)--Amphibolite- to<br />

granulite-facies quartz<strong>of</strong>eldspathic orthogneiss <strong>and</strong> paragneiss, commonly<br />

garnet-bearing, <strong>and</strong> felsic granulite. Minor amounts <strong>of</strong> intermediate to<br />

mafic orthogneiss, granulite, <strong>and</strong> charnockite. Metamorphosed iron<br />

formations <strong>and</strong> ferruginous quartzite are shown by dotted lines on map.<br />

Older than 2,800 Ma, <strong>the</strong> protolith is probably as old as 3,400 to 3,700<br />

Ma (Sidder <strong>and</strong> Mendoza-S., 1991)<br />

METAMORPHIC ROCKS<br />

Xmo - Moriche Formation (Early Proterozoic)--Characterized at its type<br />

locality (Cerro Moriche on <strong>the</strong> middle Río Ventuari, lat 4°40' N., long<br />

66°25' W.) as metasedimentary conglomerates, possible remnants <strong>of</strong> an<br />

ancestral greenstone belt terrane eroded from <strong>the</strong> protolith (Ghosh,<br />

1985). These rocks are highly magnetic <strong>and</strong> commonly follow major<br />

structural lows along <strong>the</strong> middle <strong>and</strong> upper Río Orinoco <strong>and</strong> Río Mavaca.<br />

They generally form long, linear bodies, some <strong>of</strong> which are folded by<br />

regional metamorphic events, <strong>and</strong> are usually visible in <strong>the</strong> SLAR imagery<br />

Xmp - Intrusive rocks <strong>of</strong> <strong>the</strong> San Carlos metamorphic-plutonic terrane (Early<br />

Proterozoic)—-Covering large parts <strong>of</strong> <strong>the</strong> sou<strong>the</strong>rn Amazonas Federal<br />

Territory. These rocks are named for <strong>the</strong> type locality at San Carlos de<br />

Río Negro (lat 1°50' N., long 67°05'W.) <strong>and</strong> crop out along most <strong>of</strong> <strong>the</strong><br />

Río Guainía <strong>and</strong> Río Negro. They are described as granite, graniteporphyry,<br />

granite-gneiss, <strong>and</strong> augen-gneiss with relatively abundant<br />

pegmatites (Marcano <strong>and</strong> o<strong>the</strong>rs, 1991). This terrane is characterized by<br />

strong, sinuous, east-west- to N. 70° W.-trending, elongate magnetic<br />

anomalies stacked toge<strong>the</strong>r<br />

Xbc - Basement complex (Early Proterozoic)—Foliated granite to granodiorite<br />

gneiss<br />

Linear features:<br />

Contact, dashed where inferred primarily from magnetic data<br />

Fault, dashed where inferred, dotted where implied. Includes lineaments<br />

recognized on SLAR<br />

Fault, transverse, arrows show relative movement where known<br />

Fault, thrust, sawteeth on upper plate<br />

Fault--Bar <strong>and</strong> ball on downthrown side; dashed where inferred<br />

Fold axis, anticline, overturned anticline, syncline<br />

Graben bounding fault, tics on downthrown side, dashed where inferred<br />

Major deep penetrating shear zone inferred from geologic mapping <strong>and</strong> radar imagery<br />

U or Th anomaly<br />

Linear, curvalinear, to circular structural features recognized on SLAR<br />

Ring structure <strong>of</strong> unknown origin visible in SLAR--In some cases may represent a<br />

volcanic caldera<br />

B<strong>and</strong>ed iron formation <strong>and</strong> quartzite <strong>of</strong> <strong>the</strong> Imataca complex<br />

Axis <strong>of</strong> strong pervasive magnetic gradient--May represent major hidden fault or<br />

suture; U, upthrown side; D, downthrown side<br />

Water contact<br />

Single line tributary<br />

International boundary

---

Province boundary<br />

Paved road<br />

Point features:<br />

Outcrop<br />

Unimproved airstrip<br />

Settlement<br />

Bedding<br />

Foliation<br />

Joint, vertical joint<br />

Inclined cleavage<br />

Sinkhole