CA2478136A1 - Determining the pressure of formation fluid in earth formations surrounding a borehole - Google Patents
Determining the pressure of formation fluid in earth formations surrounding a borehole Download PDFInfo
- Publication number
- CA2478136A1 CA2478136A1 CA002478136A CA2478136A CA2478136A1 CA 2478136 A1 CA2478136 A1 CA 2478136A1 CA 002478136 A CA002478136 A CA 002478136A CA 2478136 A CA2478136 A CA 2478136A CA 2478136 A1 CA2478136 A1 CA 2478136A1
- Authority
- CA
- Canada
- Prior art keywords
- pressure
- tool
- cavity
- volume
- formation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B49/00—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
- E21B49/08—Obtaining fluid samples or testing fluids, in boreholes or wells
- E21B49/10—Obtaining fluid samples or testing fluids, in boreholes or wells using side-wall fluid samplers or testers
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B49/00—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
- E21B49/008—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells by injection test; by analysing pressure variations in an injection or production test, e.g. for estimating the skin factor
Landscapes
- Geology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- Physics & Mathematics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Sampling And Sample Adjustment (AREA)
- Geophysics And Detection Of Objects (AREA)
- Measuring Fluid Pressure (AREA)
Abstract
A method for determining formation fluid pressure in earth formation surrounding a borehole wall uses a downhole probe coupled to a variable-volume cavity. The probe is driven into contact with formation at the borehole wall. The method includes expanding the volume of the cavity during a first period of time to establish fluid communication between tool fluid and formation fluid, by withdrawing a minimal amount of fluid from the formation. During a second period of time the tool pressure is allowed to equilibrate to formation pressure. When pressure equilibrium is established, formation fluid pressure is set equal to tool pressure. A
preferred embodiment includes terminating expanding the volume of the cavity on detecting a break in the mud cake seal. An associated formation pressure tester tool includes an elongated body; a probe defining a formation fluid inflow aperture, an electromechanical assembly defining a variable-volume cavity, a pretest flow line coupling the aperture to the cavity, a pressure sensor coupled to the cavity; and downhole electronic means for controlling the expansion of the volume of the cavity.
preferred embodiment includes terminating expanding the volume of the cavity on detecting a break in the mud cake seal. An associated formation pressure tester tool includes an elongated body; a probe defining a formation fluid inflow aperture, an electromechanical assembly defining a variable-volume cavity, a pretest flow line coupling the aperture to the cavity, a pressure sensor coupled to the cavity; and downhole electronic means for controlling the expansion of the volume of the cavity.
Claims (23)
1. A method for determining formation fluid pressure in earth formation surrounding a borehole, the borehole defining a borehole wall, the method comprising:
pressing a probe into contact with mud cake and formation at the borehole wall;
expanding the volume of a variable-volume pretest cavity that is in fluid communication with the probe during a draw-down period to break a mud cake seal at the probe;
terminating expanding the volume of the cavity on detecting a break in the mud cake seal;
allowing a build-up period to establish pressure equilibrium between tool fluid and formation fluid;
measuring tool pressure; and setting formation fluid pressure equal to tool pressure at pressure equilibrium.
pressing a probe into contact with mud cake and formation at the borehole wall;
expanding the volume of a variable-volume pretest cavity that is in fluid communication with the probe during a draw-down period to break a mud cake seal at the probe;
terminating expanding the volume of the cavity on detecting a break in the mud cake seal;
allowing a build-up period to establish pressure equilibrium between tool fluid and formation fluid;
measuring tool pressure; and setting formation fluid pressure equal to tool pressure at pressure equilibrium.
2. A method according to claim 1, wherein detecting a break in the mud cake seal includes measuring tool pressure and detecting an abrupt change associated with tool pressure.
A method according to claim 2, wherein detecting the abrupt change includes using a finite moving average (FMA) algorithm on a function of tool pressure.
4. A method according to claim 3, wherein the function of tool pressure includes tool pressure.
5. A method according to claim 3, wherein the function of tool pressure includes a first derivative of tool pressure.
6. A method according to claim 3, wherein the function of tool pressure includes a second derivative of tool pressure.
7. A method according to claim 1, wherein detecting a break in the mud cake seal includes detecting a difference between a measured tool pressure and a corresponding tool pressure from a reference tool pressure profile.
8. A method according to claim 7, wherein the reference tool pressure profile is measured in a previous drawdown with the cavity isolated from the formation.
9. A method according to claim 1, further comprising:
expanding the volume of the cavity during the draw-down period at a predetermined constant rate.
expanding the volume of the cavity during the draw-down period at a predetermined constant rate.
10. A method according to claim 9, wherein the predetermined constant rate is within the range of 3-160cc/minute.
11. A method according to claim 10, wherein the predetermined constant rate is approximately 5cc/minute.
12. A tool for determining formation fluid pressure in earth formation surrounding a borehole, the borehole defining a borehole wall, the tool comprising:
an elongated body adapted for downhole operation;
a probe, extendable from the elongated body, the probe defining an inflow aperture;
a pretest piston pump defining a variable-volume pretest cavity;
a pretest flow line coupling the inflow aperture to the cavity;
pressure measuring means, pressure-coupled to the cavity for measuring tool pressure; and electromechanical control means for controlling the volume of the cavity.
an elongated body adapted for downhole operation;
a probe, extendable from the elongated body, the probe defining an inflow aperture;
a pretest piston pump defining a variable-volume pretest cavity;
a pretest flow line coupling the inflow aperture to the cavity;
pressure measuring means, pressure-coupled to the cavity for measuring tool pressure; and electromechanical control means for controlling the volume of the cavity.
13. A tool according to claim 12, wherein the control means includes an electromechanically driven roller screw planetary system.
14. A tool according to claim 13, wherein the control means further includes an electrically driven gearbox coupled to drive the roller screw planetary system.
15. A tool according to claim 12, wherein the control means includes downhole programmable control electronics coupled to control the electromechanical control means.
16. A tool according to claim 12, wherein the tool includes a constant-volume flow line.
17. A tool according to claim 16, wherein the constant-volume flow line includes a dedicated probe.
18. A tool according to claim 16, wherein the constant-volume flow line includes a flexible conduit.
19. A tool according to claim 16, wherein the constant-volume flow line has a volume in the range 20 - 120cc.
20. A tool according to claim 12, wherein the probe is located between the pressure measuring means and the variable-volume pretest cavity.
21. A tool according to claim 12, further comprising a sample line coupled to the cavity, and an isolation valve located between the cavity and the sample line.
22. A tool according to claim 12, further comprising an isolation valve located between the cavity and the formation fluid inflow aperture.
23. A tool according to claim 12, wherein said electromechanical control means includes means for terminating expansion of the volume of the cavity on detecting a break in a mud cake seal.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US10/644,284 US7178392B2 (en) | 2003-08-20 | 2003-08-20 | Determining the pressure of formation fluid in earth formations surrounding a borehole |
| US10/644,284 | 2003-08-20 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2478136A1 true CA2478136A1 (en) | 2005-02-20 |
| CA2478136C CA2478136C (en) | 2012-07-10 |
Family
ID=34194049
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2478136A Expired - Fee Related CA2478136C (en) | 2003-08-20 | 2004-08-17 | Determining the pressure of formation fluid in earth formations surrounding a borehole |
Country Status (2)
| Country | Link |
|---|---|
| US (1) | US7178392B2 (en) |
| CA (1) | CA2478136C (en) |
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| US8899323B2 (en) | 2002-06-28 | 2014-12-02 | Schlumberger Technology Corporation | Modular pumpouts and flowline architecture |
| US7805247B2 (en) * | 2002-09-09 | 2010-09-28 | Schlumberger Technology Corporation | System and methods for well data compression |
| US7266983B2 (en) * | 2002-09-12 | 2007-09-11 | Baker Hughes Incorporated | Methods to detect formation pressure |
| US6923052B2 (en) * | 2002-09-12 | 2005-08-02 | Baker Hughes Incorporated | Methods to detect formation pressure |
| US20080087470A1 (en) | 2005-12-19 | 2008-04-17 | Schlumberger Technology Corporation | Formation Evaluation While Drilling |
| US7367394B2 (en) * | 2005-12-19 | 2008-05-06 | Schlumberger Technology Corporation | Formation evaluation while drilling |
| US7594541B2 (en) * | 2006-12-27 | 2009-09-29 | Schlumberger Technology Corporation | Pump control for formation testing |
| US7542853B2 (en) * | 2007-06-18 | 2009-06-02 | Conocophillips Company | Method and apparatus for geobaric analysis |
| US8136395B2 (en) * | 2007-12-31 | 2012-03-20 | Schlumberger Technology Corporation | Systems and methods for well data analysis |
| US7753117B2 (en) * | 2008-04-04 | 2010-07-13 | Schlumberger Technology Corporation | Tool and method for evaluating fluid dynamic properties of a cement annulus surrounding a casing |
| US7753118B2 (en) * | 2008-04-04 | 2010-07-13 | Schlumberger Technology Corporation | Method and tool for evaluating fluid dynamic properties of a cement annulus surrounding a casing |
| US20100014748A1 (en) * | 2008-07-21 | 2010-01-21 | International Business Machines Corporation | Method and apparatus for real time fault detection in high speed semiconductor processes |
| US8596384B2 (en) * | 2009-02-06 | 2013-12-03 | Schlumberger Technology Corporation | Reducing differential sticking during sampling |
| US8522611B2 (en) * | 2009-02-19 | 2013-09-03 | Baker Hughes Incorporated | Method and apparatus for measuring pore pressure beyond the casing |
| GB2492681B (en) * | 2010-02-20 | 2015-11-04 | Halliburton Energy Services Inc | Systems and methods of a sample bottle assembly |
| US20110214879A1 (en) * | 2010-03-03 | 2011-09-08 | Baker Hughes Incorporated | Tactile pressure sensing devices and methods for using same |
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| US9097106B2 (en) * | 2012-03-30 | 2015-08-04 | Schlumberger Technology Corporation | Apparatus, method and system for measuring formation pressure and mobility |
| US20140182836A1 (en) * | 2013-01-02 | 2014-07-03 | Cyrus Aspi Irani | Apparatus for Collecting a Representative Fluid Sample |
| ES2762510T3 (en) | 2013-03-15 | 2020-05-25 | Hayward Ind Inc | Modular pool / whirlpool control system |
| US20150176389A1 (en) * | 2013-12-20 | 2015-06-25 | Schlumberger Technology Corporation | Detection And Identification Of Fluid Pumping Anomalies |
| WO2017015340A1 (en) | 2015-07-20 | 2017-01-26 | Pietro Fiorentini Spa | Systems and methods for monitoring changes in a formation while dynamically flowing fluids |
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-
2003
- 2003-08-20 US US10/644,284 patent/US7178392B2/en not_active Expired - Lifetime
-
2004
- 2004-08-17 CA CA2478136A patent/CA2478136C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CA2478136C (en) | 2012-07-10 |
| US20050039527A1 (en) | 2005-02-24 |
| US7178392B2 (en) | 2007-02-20 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |
Effective date: 20200831 |