|Número de publicación||US3500913 A|
|Tipo de publicación||Concesión|
|Fecha de publicación||17 Mar 1970|
|Fecha de presentación||30 Oct 1968|
|Fecha de prioridad||30 Oct 1968|
|Número de publicación||US 3500913 A, US 3500913A, US-A-3500913, US3500913 A, US3500913A|
|Inventores||Closmann Philip J, Nordgren Ronald P|
|Cesionario original||Shell Oil Co|
|Exportar cita||BiBTeX, EndNote, RefMan|
|Citas de patentes (4), Citada por (69), Clasificaciones (10)|
|Enlaces externos: USPTO, Cesión de USPTO, Espacenet|
Marsh 17,, 1970 NQFZDGREN EI'AL 3,5@Q,913 METHOD OF REGOVERING LIQUEFIABLE COMPONENTS FROM A SUBTERRANEAN EARTH FORMATION Filed 0G1.- 50, 1968 ULTIMATE COMMUNICATION l6 GAS Q AlR SEPARATOR 4 OIL um HEAT EXCHANGER INVENTORSI R. P. NORDGREN P. J. CLOSMANN THEIR ATTORNEY United States Patent U.S. Cl. 166-259 8 Claims ABSTRACT OF THE DISCLOSURE A method of recovering liquefiable components from a normally impermeable subterranean earth formation by extending at least a pair of well boreholes into the formation and forming generally vertical fractures extending along generally parallel paths from each of the boreholes. Hot fluid is injected through at least one of the well boreholes until flow into at least one of the fractures therein is thermally closed by the swelling-shut of the walls of the fracture. Fluid in at least one borehole in which fractures have been thermally closed is pressurized until at least one new fracture is formed and the steps of injecting hot fluid and pressurizing fluid are repeated at successively higher temperatures and pressures until the resultant fractures form a channel interconnecting the well boreholes through which channel fluid can flow from one well borehole to another. Finally, hot fluid is circulated, by injection into one of the boreholes opening into the fracture channel, with fluid being produced from another of the boreholes opening into the fracture channel, at a temperature below that at which the last fracture was opened in the well borehole into which the circulating fluid is injected but above that at which the last fracture was thermally closed within the well borehole into which the circulating fluid is injected, so that most of the injected fluid is conveyed through fractures interconnecting the boreholes.
BACKGROUND OF THE INVENTION Field of the invention This invention relates to a method for recovering liquefiable components from a relatively impermeable subterranean earth formation, normally subjected to vertical fracturing.
Description of the prior art It is known that it is extremely difficult to recover liquefiable components from depths of various subterranean impermeable formations such as oil shale, coral, bed deposits of cinnabar, etc., under conditions in which the deposits are normally present in these formations. Various proposals have been made, such as described in a U.S. Patent No. 3,284,281, to recover oil from oil shale. Therein oil shale is produced from an oil shale formation through fractures. However, under the conditions described therein, the fractures tend to close as their walls become heated and thermally expanded and oil recovery is stopped. Under conditions described, it is generally necessary to resort to a repeating sequence of fracturing, heating and expanding and refracturing operations until flow patterns are finally formed that will remain open while the desired components are being liquefied.
In certain situations, particularly at relatively shallow depths, a heating procedure can be utilized to cause the swelling tendencies of the earth formations to create horizontal stresses that exceed the vertical stresses. By such procedure, pairs of wells can be interconnected by means of a horizontal fracture that can be kept open by hydrau- 3,500,913 Patented Mar. 17, 1970 lically lifting or compressing the overlying earth formations. Such a procedure, in which the heating is accomplished by injecting a liquid while maintaining a specified rate of fluid flow and temperature increase, is described in a copending application to Matthews et al., Ser. No. 578,533 filed Sept. 12, 1966, now Patent No. 3,455,391.
However, in many situations, horizontal fractures cannot feasibly be formed by thermally increasing the horizontal stresses. Generally, the heating of oil shale formations causes the vertical stresses to increase at a rate comparable to that at which the horizontal stresses are increased, and this prevents the formation of a horizontal fracture. Although communication between wells might be established by repetitively heating and fracturing at successively higher pressures and temperatures, as proposed in the aforementioned U.S. patent, this would result in excessively high operating costs and the production and maintenance of higher pressures and temperatures than are actually required.
When the regional tectonics are such that vertical fractures form and propagate along generally parallel paths when fluid is injected into adjacent wells at about the nor mal subsurface temperature at pressures and rates suflicient to form and extend the fractures, the use of successively higher pressures and temperatures is apt to form a succession of numerous differently-oriented vertical fractures at pressures which do not become high enough to produce a horizontal fracture. The pressure necessary to form a horizontal fracture is generally about equal to or slightly less than one p.s.i. per foot of depth. When, for example, a vertical fracture opening into a first well has been extended for a significant distance and at least one vertical fracture has been opened and then thermally closed in a second well, the formation and extension of a subsequent fracture from the second well is apt to cause the fractures to intersect so that fluid can flow from one well to the other. However, if the fluid pumped through such intersecting fractures is heated at or above the temperature at which the last fracture was formed, the walls of the fracture will swell and the flow path will close.
SUMMARY OF THE INVENTION It is an object of this invention to provide a method of recovering liquefiable components from a normally impermeable subterranean earth formation by extending generally vertical fractures between wells extending into the formation.
It is a further object of this invention to provide a method of interconnecting wells extending into normally impermeable subterranean earth formations by forming generally vertical fractures between such wells.
It is a still further object of this invention to interconnect wells extending into subterranean earth formations by means of generally vertical fractures which remain open so that fluid flow remains unrestricted between such wells.
These objects are preferably attained by forming generally vertical fractures extending along generally parallel paths from at least a pair of well boreholes extending into a relatively impermeable subterranean earth formation by injecting a hot fluid through at least one of the Well boreholes until flow into at least one of the fractures therein is thermally closed by the swelling-shut of the walls of the fracture. The fluid in at least one borehole in which fractures have been thermally closed is pressurized until at least one new fracture is formed and the steps of injecting hot fluid and pressurizing fluid are repeated at successively higher temperatures and pressures until the resultant fractures form a channel interconnecting the well boreholes, through which channel fluid can flow from one borehole to another. Finally, hot fluid is cirulated, by injecting into one of the boreholes opening no the fracture channel, with fluid being produced from nother of the boreholes opening intothe fracture chane1, at a temperature below that at which the last fracure was opened into the well borehole into which the irculating fluid is injected but above that which the last racture was thermally closed Within the well borehole 1to which the circulating fluid is injected so that most f the injected fluid is conveyed through fractures interonnecting the boreholes.
When such a flow path is opened between a pair of vells, the path may be kept open by lowering the tem- Ierature of the fluid pumped through the path to a temuerature that is less than that at which the last fracture /as formed but greater than that at which the next preeding fracture was thermally closed. In addition, if the ffective permeability of the flow path between the well oreholes is then increased by circulating through it a luid that removes solid components from the walls of he fractures, the flow path is converted to one through vhich the flow of fluid from one well borehole to the other emains eflicient at whatever temperature is subsequently rnparted to the fluid.
The attainment of a significant increase in the effective Iermeability of such a flow path may be detected by an ncrease in the rate of flow in response to the injection ressure that was initially required to displace fluid from -ne well borehole to another. If the temperature of the ;irculating fluid is too high relative to the rate at which )ermeability is being increased, this may be detected by a 'eduction in the flow rate. If the temperature is too low elative to the rate at which the permeability is being ncreased, this may be detected by a decrease in the rate )f outflow from the production well borehole without a :orresponding decrease in rate of inflow into the injection vell borehole. Where the temperature is too high, the heremal closing of the last-opened fracture throttles the low and where the temperature is too low, a thermal )pening of previously closed fractures divert the flow )f the injected fluid.
BRIEF DESCRIPTION OF THE DRAWING FIGURE 1 is a top plan view of a preferred arrangenent of well boreholes extending into a subterranean :arth formation; and
FIGURE 2 is a vertical sectional view of the well oreholes of FIGURE 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing, FIGURE 1 shows a air of well boreholes 11 and 12 extending into an earth Formation 13 overlying a normally impermeable suberranean earth formation such as an oil shale formation Knot shown). Generally vertical fractures are first formed :xtending along generally parallel paths from each of vell boreholes 11 and 12 which open into the subterranean :arth formation. Such fractures may be formed by any .echnique for applying a fluid pressure above the breaklown pressure of earth formation 13 but below the over- Jurden pressure of earth formation 13. Of course, tlthough two such well boreholes 11 and 12 are illustrated n FIGURE 1, obviously a plurality of such well bore- 1oles may be opened into the selected earth formation 1nd treated simultaneously or sequentially, in any order.
In a preferred procedure for interconnecting well boreioles 11 and 12, a vertical fracture 14 is extended from vell borehole 11 for a significant distance along a natural )13116 of weakness with the subterranean formation. Conentional subterranean stress analyses techniques and/or techniques for measuring the orientation of fractures may )e utilized to determine the direction along which the fracture 14 is extended. This fracture 14 is preferably propped by procedures well known in the the art. Well borehole 12, preferably having been drilled after the formation of fracture 14, is preferably completed near an intersection of a preselected well borehole-to-well borehole spacing distance and the fracture 14 opening into well borehole 11. Of course, if suflicient communication between well borehole 11 and 12 results from drilling well borehole 12 with the intention of intersecting fracture 14, further fracturing is not necessary. However, in most cases, an initial fracture 15 must be then produced in Well borehole 12 and left unpropped and thermally closed, by the method discussed in a copending application to Matthews et al. Ser No. 578,533, filed Sept. 12, 1966, wherein a liquid is pumped into a fracture within a subsurface earth formation while heating the inflowing liquid as preferably a surface location and maintaining a flow rate that is adequate for transporting heat from the heating location to the fracture. The flow rate and the rate at which the inflowing liquid is heated to temperatures preferably increasingly greater than the earth formation temperature are correlated so that the liquid remains hotter than the fracture walls until the liquid has moved a significant distance away from the well. The pressure at which the liquid is injected is increased as required in order to maintain an adequate rate of flow. The heating and pumping of the liquid are continued until the pressure at which the liquid is injected exceeds the overburden pressure and produces a horizontal fracture within the subsurface earth formation.
Thus, hot fluid may be injected into well borehole 12 until the flow into at least one of the generally vertical fractures, such as fracture 15, is thermally closed by the swelling shut of the fracture walls. Fluid in well borehole 11 in which fracture 15 has been thermally closed is then pressurized until at least one new fracture, such as fracture 17, extending from well borehole 12, is formed;
The injection of a hot fluid, such as hot water, into fracture 15 results in a gradual closing of the fractures and loss of injectivity. Continued injection of hot water, however, at suflicient pressure may cause additional vertical fractures, such as fractures 16 and/or 18 extending from well borehole 12, to form, since heating generally results in a horizontal stress comparable to or less than the vertical stress developed. Additional injection of hot water may cause fractures such as fractures 16 or 18 extending from well borehole 12, to be developed. These fractures are formed radially extending from their respective well boreholes, but, at great distances from their respective well boreholes, they generally follow some preferential alignment in the oil field. It is likely, however, that two or more of these fractures from the two well boreholes 11 and 12, for example, intersect and provide fluid communication between well boreholes 11 and 12, if injection pressure is suflicient. The use of slant well boreholes may improve chances of intercommunication.
Thus, as illustrated in FIGURE 1, these steps are repeated at successively higher temperatures and pressures to the extent required to form the interconnecting fractures, such as fractures 16, 18, and 14, through which fluid may flow from well borehole 11 to well borehole 12. Such fractures, as for example fracture 18, may be on a plane at a generally right angle to fracture 15 and thus may be extended by means well known in the art to a position intersecting fracture 14. When a subsequent fracture from well borehole 12 intersects with one from well borehole 11, as for example fracture 18 in FIGURE 1, it is propped, with the propping agent being injected while circulating fluid at a controlled temperature. This is accomplished by circulating fluid, by injection into injection well borehole 11, for example, and producing it from production well borehole 12, again for example, which opens into an interconnecting fracture, such as fractures 14 and 16. The fluid is preferably circulated at a temperature below that at which the last fracture was open into the injection well borehole 11 but above that at which the last fracture was thermally closed within the injection well borehole 11 so that most of the injected fluid is conveyed through the interconnecting fractures.
In injecting hot fluid through well borehole 12 until flow into at least one of the generally vertical fractures, such as fracture 15, is thermally closed by the swelling shut of the fracture walls, the hot fluid may be any gas and/or liquid that is heated at the surface of the earth formation 13, in the well borehole and/or in situ, e.g., by underground combustion, in the subterranean earth formation. The heated fluid may be the same as or different from the fracturing fluid and the heating may be initiated before or after the fracturing.
In circulating fluid into injection well borehole 11 and producing it from production well borehole 12, the circulation of such fluid may be continuous or intermittent and the circulated fluid may be any liquid or gas that is injected into or produced from either of any pair of well boreholes. Where one well borehole of a pair of well boreholes is fractured only once, as for example well borehole 11 of FIGURE 1, and the circulating fluid is injected through it, the temperature of the circulating fluid may be as low as desired.
Preferably, the temperature of the hot fluid being injected to form and extend a subsequent fracture in a well borehole in which a preceding fracture was thermally closed, is adjusted and a propping agent is mixed with the inflowing fluid. Once inter-well communication has been established, hot fracturing fluid injection may be discontinued and a reacting fluid may be flowed therethrough.
The composition of the reaction fluid is preferably adjusted to the extent required to circulate fluid that removes solid materials from the walls of the interconnecting fractures without a significant reduction in the average rate of flow between well boreholes 11 and 12, so that the effective permeability of the interconnecting fractures, as for example fractures 14 and 16, is increased relative to fluid flowing between well boreholes 11 and 12. Solid-materialremoving components may be incorporated into the react ing fluid being circulated through the interconnecting fractures without interrupting the flow to an extent that permits the fractures to close and reseal. In treating a subterranean oil shale formation, such components may comprise hot benzene, steam, or other solvent, or nitric acid, of a lower temperature than the hot fracturing fluid. Nitric acid has the advantage of reacting with the organic matter as well as the carbonate present in the subterranean earth formation. The injection of such a reacting fluid leaches out part of the kerogen adjoining the faces of the interconnecting fractures. The injection at a lower temperature and at substantially the same injection pressure permits the fractures to open slightly for better passage of the fluids. The temperature of the solid-material-removing fluid may be increased as the permeability of the interconnecting fractures, fractures 14 and 16, for example, is increased until the circulating fluid becomes hot enough to liquefy the liquefiable components of the subterranean earth formatron.
Following or during the hot solvent injection as discussed hereinabove, acid may be injected to react with part of the rock matrix along the fracture walls. This acid injection renders the channels even more permeable.
After all the steps discussed hereinabove are carried out, an underground combustion process, as is well known in the art, which develops considerably higher temperatures, may be undertaken. The steps of leaching out part of the kerogen and the rock generally make closure of the fracture paths during combustion very unlikely. In this manner, it is possible to treat a substantial part of the formation by underground combustion.
Thus, as illustrated in FIGURE 1, uniform temperature zones 21 and 22 may be seen surrounding well boreholes 11 and 12, respectively. Also, advancing combustion fronts 23 and 24, initiated and alternatingly advanced, for example, by means well known in the art, may be formed about well boreholes 11 and 12, respectively.
FIGURE 2 shows permeable channel 25 formed in the subterranean earth formation of FIGURE 1 by the foregoing method of this invention. Injection well borehole 11 is preferably equipped with casing 23 cemented therein and sealed with cement. A tubing string 29 is disposed in well borehole 11 and packed off at packer 34. Conventional heating, pumping, heat exchanging and separating equipment are associated with well boreholes l1 and 12 for injecting fluid from well borehole 11 through perforations 31 in well borehole 11, through the permeable channel 25 created by intersecting fractures, such as 14 and 16, into well borehole 12 through perforations 33 therein. Well borehole 12 preferably is cased with casing 34 surrounded by cement 24. Since certain subterranean earth formations, such as oil and shale deposits in Colorado, Utah, and Wyoming, are practically impermeable except for certain natural vertical fractures, the method of this invention improves injectivity and fluid communication between two or more wells from a succession of vertical fractures.
We claim as our invention:
1. In a method of recovering liquefiable components from a normally impermeable subterranean earth formation comprising the steps of:
extending at least a pair of well boreholes into said earth formations;
forming generally vertical fractures extending along generally parallel paths from each of said pair of well boreholes;
injecting hot fluid through at least one of the well boreholes until flow into at least one of the fractures therein is thermally closed by the swelling-shut of the walls of said fracture;
pressurizing fluid in at least one well borehole in which at least one fracture has been thermally closed until at least one new fracture is formed; repeating the steps of injecting hot fluid and pressurizing fluid at successively higher temperatures and pressures until the resultant fractures form a channel interconnecting said well boreholes through which fluid flows from one well borehole to another; and
circulating hot fluid, by injection into one of said well boreholes opening into said fracture channel and production from another of said well boreholes opening into said fracture channel, at a temperature below that at which the last fracture was opened into the well borehole into which said hot fluid is injected but above that at which the last fracture was thermally closed within the well borehole into which said hot fluid is injected, so that most of the injected fluid is conveyed through said fracture channel from one well borehole to another.
2. The method of claim 1 including the step of adjusting the composition of said circulating hot fluid to the extent required to circulate fluid that removes solid materials from the walls of fractures interconnecting said well boreholes without a significant reduction in the'average rate of flow between the well boreholes so that the effective permeability of the fractures interconnecting said well boreholes is increased relative to that of other fractures.
3. The method of claim 2 including the step of increasing the temperature of the circulating fluid as the permeability of the interconnected fractures is increased, with the temperature being increased to the extent required to circulate fluid capable of liquefying the liquefiable components of the solid materials removed from the walls of the interconnecting fractures.
4. The method of claim 3 including the step of recovering hydrocarbons from the liquefiable components of the circulating fluid.
5. The method of claim 3 including the step of increasing the permeability of the interconnected fractures by injecting acid therethrough adapted to react with at least 1 portion of the rock matrix forming the walls of said fractures.
6. The method of claim 3 including the step of initiating an underground combustion Within said subterranean earth formation so as to effect recovery of petroleum materials.
7. The method of claim 2 wherein the step of adjusting the composition of said circulating fluid includes the step of incorporating acidic solid-material-removing components into said circulating fluid.
8. The method of claim 7 wherein the step of incorcirculating fields includes the step of incorporating nitric acid.
References Cited UNITED STATES PATENTS 2,813,583 11/1957 Marx et a1. 166-271 3,284,281 11/1966 Thomas 166-271 X 3,346,044 10/1967 Slusser 166259 X 3,379,250 4/1968 Matthews et a1 166-271 10 CHARLES E. OCONNELL, Primary Examiner I. A. CALVERT, Assistant Examiner US. Cl. X.R.
porating solid-material-removing components into said 15 166271, 272
|Patente citada||Fecha de presentación||Fecha de publicación||Solicitante||Título|
|US2813583 *||6 Dic 1954||19 Nov 1957||Phillips Petroleum Co||Process for recovery of petroleum from sands and shale|
|US3284281 *||31 Ago 1964||8 Nov 1966||Phillips Petroleum Co||Production of oil from oil shale through fractures|
|US3346044 *||8 Sep 1965||10 Oct 1967||Mobil Oil Corp||Method and structure for retorting oil shale in situ by cycling fluid flows|
|US3379250 *||9 Sep 1966||23 Abr 1968||Shell Oil Co||Thermally controlling fracturing|
|Patente citante||Fecha de presentación||Fecha de publicación||Solicitante||Título|
|US3565173 *||17 Sep 1969||23 Feb 1971||Mobil Oil Corp||Methods of selectively improving the fluid communication of earth formations|
|US3613785 *||16 Feb 1970||19 Oct 1971||Shell Oil Co||Process for horizontally fracturing subsurface earth formations|
|US3682246 *||19 Ene 1971||8 Ago 1972||Shell Oil Co||Fracturing to interconnect wells|
|US3706341 *||8 Oct 1970||19 Dic 1972||Canadian Fina Oil Ltd||Process for developing interwell communication in a tar sand|
|US3810510 *||15 Mar 1973||14 May 1974||Mobil Oil Corp||Method of viscous oil recovery through hydraulically fractured wells|
|US3863709 *||20 Dic 1973||4 Feb 1975||Mobil Oil Corp||Method of recovering geothermal energy|
|US3978925 *||21 Jun 1974||7 Sep 1976||Texaco Exploration Canada Ltd.||Method for recovery of bitumens from tar sands|
|US4006778 *||21 Jun 1974||8 Feb 1977||Texaco Exploration Canada Ltd.||Thermal recovery of hydrocarbon from tar sands|
|US4438976 *||6 Ago 1982||27 Mar 1984||Occidental Research Corporation||Method of repair of short circuits for in situ leaching|
|US7441603||30 Jul 2004||28 Oct 2008||Exxonmobil Upstream Research Company||Hydrocarbon recovery from impermeable oil shales|
|US7563750 *||21 Jul 2009||Halliburton Energy Services, Inc.||Methods and compositions for the diversion of aqueous injection fluids in injection operations|
|US7631691||15 Dic 2009||Exxonmobil Upstream Research Company||Methods of treating a subterranean formation to convert organic matter into producible hydrocarbons|
|US7669657||2 Mar 2010||Exxonmobil Upstream Research Company||Enhanced shale oil production by in situ heating using hydraulically fractured producing wells|
|US7857056||15 Oct 2008||28 Dic 2010||Exxonmobil Upstream Research Company||Hydrocarbon recovery from impermeable oil shales using sets of fluid-heated fractures|
|US8082995||27 Dic 2011||Exxonmobil Upstream Research Company||Optimization of untreated oil shale geometry to control subsidence|
|US8087460||3 Ene 2012||Exxonmobil Upstream Research Company||Granular electrical connections for in situ formation heating|
|US8104537||31 Ene 2012||Exxonmobil Upstream Research Company||Method of developing subsurface freeze zone|
|US8122955||18 Abr 2008||28 Feb 2012||Exxonmobil Upstream Research Company||Downhole burners for in situ conversion of organic-rich rock formations|
|US8146664||21 May 2008||3 Abr 2012||Exxonmobil Upstream Research Company||Utilization of low BTU gas generated during in situ heating of organic-rich rock|
|US8151877||18 Abr 2008||10 Abr 2012||Exxonmobil Upstream Research Company||Downhole burner wells for in situ conversion of organic-rich rock formations|
|US8151884||10 Oct 2007||10 Abr 2012||Exxonmobil Upstream Research Company||Combined development of oil shale by in situ heating with a deeper hydrocarbon resource|
|US8230929||31 Jul 2012||Exxonmobil Upstream Research Company||Methods of producing hydrocarbons for substantially constant composition gas generation|
|US8540020||21 Abr 2010||24 Sep 2013||Exxonmobil Upstream Research Company||Converting organic matter from a subterranean formation into producible hydrocarbons by controlling production operations based on availability of one or more production resources|
|US8596355||10 Dic 2010||3 Dic 2013||Exxonmobil Upstream Research Company||Optimized well spacing for in situ shale oil development|
|US8616279||7 Ene 2010||31 Dic 2013||Exxonmobil Upstream Research Company||Water treatment following shale oil production by in situ heating|
|US8616280||17 Jun 2011||31 Dic 2013||Exxonmobil Upstream Research Company||Wellbore mechanical integrity for in situ pyrolysis|
|US8622127||17 Jun 2011||7 Ene 2014||Exxonmobil Upstream Research Company||Olefin reduction for in situ pyrolysis oil generation|
|US8622133||7 Mar 2008||7 Ene 2014||Exxonmobil Upstream Research Company||Resistive heater for in situ formation heating|
|US8641150||11 Dic 2009||4 Feb 2014||Exxonmobil Upstream Research Company||In situ co-development of oil shale with mineral recovery|
|US8701788||22 Dic 2011||22 Abr 2014||Chevron U.S.A. Inc.||Preconditioning a subsurface shale formation by removing extractible organics|
|US8770284||19 Abr 2013||8 Jul 2014||Exxonmobil Upstream Research Company||Systems and methods of detecting an intersection between a wellbore and a subterranean structure that includes a marker material|
|US8839860||22 Dic 2011||23 Sep 2014||Chevron U.S.A. Inc.||In-situ Kerogen conversion and product isolation|
|US8851177||22 Dic 2011||7 Oct 2014||Chevron U.S.A. Inc.||In-situ kerogen conversion and oxidant regeneration|
|US8863839||15 Nov 2010||21 Oct 2014||Exxonmobil Upstream Research Company||Enhanced convection for in situ pyrolysis of organic-rich rock formations|
|US8875789||8 Ago 2011||4 Nov 2014||Exxonmobil Upstream Research Company||Process for producing hydrocarbon fluids combining in situ heating, a power plant and a gas plant|
|US8936089||22 Dic 2011||20 Ene 2015||Chevron U.S.A. Inc.||In-situ kerogen conversion and recovery|
|US8992771||25 May 2012||31 Mar 2015||Chevron U.S.A. Inc.||Isolating lubricating oils from subsurface shale formations|
|US8997869||22 Dic 2011||7 Abr 2015||Chevron U.S.A. Inc.||In-situ kerogen conversion and product upgrading|
|US9033033||22 Dic 2011||19 May 2015||Chevron U.S.A. Inc.||Electrokinetic enhanced hydrocarbon recovery from oil shale|
|US9080441||26 Oct 2012||14 Jul 2015||Exxonmobil Upstream Research Company||Multiple electrical connections to optimize heating for in situ pyrolysis|
|US9133398||22 Dic 2011||15 Sep 2015||Chevron U.S.A. Inc.||In-situ kerogen conversion and recycling|
|US9140109 *||29 Sep 2010||22 Sep 2015||Schlumberger Technology Corporation||Method for increasing fracture area|
|US9181467||22 Dic 2011||10 Nov 2015||Uchicago Argonne, Llc||Preparation and use of nano-catalysts for in-situ reaction with kerogen|
|US9347302||12 Nov 2013||24 May 2016||Exxonmobil Upstream Research Company||Resistive heater for in situ formation heating|
|US9394772||17 Sep 2014||19 Jul 2016||Exxonmobil Upstream Research Company||Systems and methods for in situ resistive heating of organic matter in a subterranean formation|
|US20050164894 *||24 Ene 2004||28 Jul 2005||Eoff Larry S.||Methods and compositions for the diversion of aqueous injection fluids in injection operations|
|US20070023186 *||30 Jul 2004||1 Feb 2007||Kaminsky Robert D||Hydrocarbon recovery from impermeable oil shales|
|US20080087427 *||10 Oct 2007||17 Abr 2008||Kaminsky Robert D||Combined development of oil shale by in situ heating with a deeper hydrocarbon resource|
|US20080173443 *||25 Ene 2008||24 Jul 2008||Symington William A||Methods of treating a subterranean formation to convert organic matter into producible hydrocarbons|
|US20080283241 *||18 Abr 2008||20 Nov 2008||Kaminsky Robert D||Downhole burner wells for in situ conversion of organic-rich rock formations|
|US20080289819 *||21 May 2008||27 Nov 2008||Kaminsky Robert D||Utilization of low BTU gas generated during in situ heating of organic-rich rock|
|US20090038795 *||15 Oct 2008||12 Feb 2009||Kaminsky Robert D||Hydrocarbon Recovery From Impermeable Oil Shales Using Sets of Fluid-Heated Fractures|
|US20090050319 *||18 Abr 2008||26 Feb 2009||Kaminsky Robert D||Downhole burners for in situ conversion of organic-rich rock formations|
|US20090145598 *||14 Nov 2008||11 Jun 2009||Symington William A||Optimization of untreated oil shale geometry to control subsidence|
|US20100078169 *||1 Abr 2010||Symington William A||Methods of Treating Suberranean Formation To Convert Organic Matter Into Producible Hydrocarbons|
|US20100089575 *||11 Dic 2009||15 Abr 2010||Kaminsky Robert D||In Situ Co-Development of Oil Shale With Mineral Recovery|
|US20100089585 *||15 Dic 2009||15 Abr 2010||Kaminsky Robert D||Method of Developing Subsurface Freeze Zone|
|US20100101793 *||28 Ago 2009||29 Abr 2010||Symington William A||Electrically Conductive Methods For Heating A Subsurface Formation To Convert Organic Matter Into Hydrocarbon Fluids|
|US20100218946 *||2 Sep 2010||Symington William A||Water Treatment Following Shale Oil Production By In Situ Heating|
|US20100282460 *||11 Nov 2010||Stone Matthew T||Converting Organic Matter From A Subterranean Formation Into Producible Hydrocarbons By Controlling Production Operations Based On Availability Of One Or More Production Resources|
|US20100319909 *||25 Feb 2010||23 Dic 2010||Symington William A||Enhanced Shale Oil Production By In Situ Heating Using Hydraulically Fractured Producing Wells|
|US20110132600 *||9 Jun 2011||Robert D Kaminsky||Optimized Well Spacing For In Situ Shale Oil Development|
|US20110146982 *||23 Jun 2011||Kaminsky Robert D||Enhanced Convection For In Situ Pyrolysis of Organic-Rich Rock Formations|
|US20130140020 *||29 Sep 2010||6 Jun 2013||Schlumberger Technology Corporation||Method for increasing fracture area|
|CN1875168B||30 Jul 2004||17 Oct 2012||艾克森美孚上游研究公司||Hydrocarbon recovery from impermeable oil shales|
|CN101558216B||10 Oct 2007||7 Ago 2013||埃克森美孚上游研究公司||Enhanced shale oil production by in situ heating using hydraulically fractured producing wells|
|EP1689973A1 *||30 Jul 2004||16 Ago 2006||ExxonMobil Upstream Research Company||Hydrocarbon recovery from impermeable oil shales|
|WO2005045192A1 *||30 Jul 2004||19 May 2005||Exxonmobil Upstream Research Company||Hydrocarbon recovery from impermeable oil shales|
|WO2008048455A2 *||10 Oct 2007||24 Abr 2008||Exxonmobil Upstream Research Company||Enhanced shale oil production by in situ heating using hydraulically fractured producing wells|
|Clasificación de EE.UU.||166/259, 166/272.2, 166/271|
|Clasificación internacional||E21B43/17, E21B43/16, E21B43/24|
|Clasificación cooperativa||E21B43/24, E21B43/17|
|Clasificación europea||E21B43/24, E21B43/17|