WO2023063995A1

WO2023063995A1 - Sequestration chamber and method of construction

Info

Publication number: WO2023063995A1
Application number: PCT/US2022/025233
Authority: WO
Inventors: Andrew A. MCCREA
Original assignee: Aera Energy LLC
Current assignee: Aera Energy LLC
Priority date: 2021-10-14
Filing date: 2022-04-18
Publication date: 2023-04-20
Anticipated expiration: 2024-04-14

Abstract

A subsurface sequestration chamber is constructed having a plurality of subsurface grout partitions which define respective sidewalls to collectively function as the perimeter of an underground containment chamber located in a fluid-containing stratum positioned beneath a first non-permeable stratum and above a second non-permeable stratum. The sequestration chamber can be used as underground storage of disposal fluids such as CO2.

Description

SEQUESTRATION CHAMBER AND METHOD OF CONSTRUCTION

FIELD OF THE INVENTION

[0001] The present invention relates to the field of drilling operations and more specifically to a method of construction of a subsurface sequestration chamber using multiple grout partitions.

BACKGROUND OF THE INVENTION

[0002] Government agencies have become concerned about climate change and in particular, the excess production of carbon dioxide (CO2) and the associated detrimental global effects. Besides exploring CO2 reduction, CO2 disposal efforts are being strongly considered.

[0003] Hydraulic fracturing is a well-known procedure that is particularly used as a stimulation treatment in oilfield operations. More recently, horizontal drilling and completion operations have been developed to produce oil from shale formations. A well is drilled to depth into an oil-bearing stratum and thereafter drilling orientation is changed to a horizontal lateral wellbore within the stratum. This allows for a single well to have a greater portion of the wellbore in contact with the oil-bearing stratum and thus more hydrocarbon production per well than is possible with vertical production wells.

[0004] Hydraulic fracturing has also been used in other industries, namely for protection of coal deposits to be mined and for enhancement of geothermal wells.

[0005] US Pat. Publication No. US2019/0128068 Al discloses a hydraulic fracture use for a geothermal well. This reference discloses propped fractures and grouted fractures on a single or multiple wellbores to allow for additional and more effective heat exchange capabilities within Engineered Geothermal Process. The presence of the grout is meant to increase fluid recirculation timing and therefore increase heat exchange.

[0006] China reference CN110761814A discloses the use of a horizontal well used to control water intrusion regarding coal mining operations. Water intrusion is reduced by creating an undefined fracture network to block off the roof aquifer from the solids removal efforts below the roofline.

[0007] China reference CN108222882A discloses the deployment of a wellbore style to reduce application time of multi-layer grout application within the coal mining industry. This wellbore style does not aid the coupling of grouting application with traditional fracturing techniques such as multi-planar grout application across lateral distances.

[0008] China reference CN110566118A discloses bi-directional drilling to create a fishbone wellbore that allows for multiple penetrations into several aquifers impeding water flow. The fishbone is grouted but does not use planar grout fractures to impede water flow.

[0009] The Chinese references regard coal mining operations occurring in shallower geologic structures in which horizontal fracturing is the desired outcome.

SUMMARY OF THE INVENTION

[00010] Using horizontal drilling technology, a plurality of subsurface grout partitions are created which define respective sidewalls to collectively function as the perimeter of an underground containment chamber located in a fluid-containing stratum positioned beneath a first non-permeable stratum and above a second non-permeable stratum. The available pore space within the chamber can be used for disposal of fluids, such as CO2. Underground disposal of CO2 would reduce the overall amount vented to the atmosphere. [00011] The following terms will be used in the specification.

[00012] The terms “sequestration chamber”, “containment chamber” or “chamber” is a volume of fluid-containing stratum located underneath a non-permeable stratum and having a perimeter defined by sidewalls. Each sidewall substantially inhibits fluid flow and can either be a geologic structure such as an impermeable anticline or more preferably, artificially created grout partitions as will be discussed below.

[00013] The term “panel” refers to the concretion of a grout slurry within a fissure. A panel is created by using a pathway such as a treatment sleeve or perforations as described below, used to create one or more fissures by hydro fracture and pumping a pre-determined volume of a grout slurry through the pathway and into the fissure.

[00014] The term “hydro fracture” refers to the technique of using a liquid or slurry pumped down a casing string at a sufficient pressure to create a fissure in the stratum adjacent to a pathway.

[00015] The term “partition” refers collectively to the plurality of panels created along the lateral portion of a well.

[00016] The term “lateral portion” refers to the near horizontal inclination of casing that has been set in a hole created by horizontal drilling.

[00017] The term “grout” refers to a low permeable composition. Cement is a type of grout.

[00018] The term “treatment fluid" refers to any mix of water with polymers or chemical additives that are commonly used to initiate or propagate a hydraulic fracture preceding the pumping of the fracture-filling grout slurry. [00019] The term “treatment sleeve” refers to a mechanically or hydraulically actuated port that is part of the lateral portion of the casing string.

[00020] The chamber isolates the available pore space within from the surface and surrounding strata. Depending on the subsurface geologic structure and desired size of the sequestration chamber and adjacent geology, it may be necessary to drill more than one horizontal well, each well having one or more lateral portions in series to form one sidewall of the chamber.

[00021] The chamber is designed to be used within subsurface strata having the desirable porosity and permeability to receive a fluid via at least one injection well. Depending on the overall volume of the sequestration chamber, multiple injection wells can be utilized. Preferably, the chamber is designed for storage of a fluid such as CO2, which has a similar density as water. In the case of CO2, the sequestration chamber requires a minimum true vertical depth of at least 792 meters (2,600 ft) so injected CO2 will remain in supercritical state under normal pressure conditions.

[00022] One preferred location for a sequestration chamber would be a portion of an existing oilfield having had hydrocarbon and water extraction. FIG. 1 (prior art) is a representation of an oilfield OF having a plurality of producing wells 18. The chamber 100 can be constructed to be in the general shape of a three-sided (triangular prism), or a four-sided (square prism) as generally depicted in FIG. 2, or having any other number of sides. In order to create such a chamber, the following steps would be taken: 1) selecting the size of the perimeter for the chamber as well as identifying its intended location; 2) unless a non- permeable geologic stratum is used as a portion of the perimeter, each side of the perimeter would be formed by: a) drilling a well having a lateral portion; b) running casing within the lateral portion having a series of treatment sleeves spaced along the length of the lateral portion; c) opening the deepest treatment sleeve and conducting hydraulic fracturing; d) pumping within the created fracture a volume of non-permeable grout slurry; and e) closing the treatment sleeve. Steps c-e would be repeated for each treatment sleeve.

[00023] The sidewalls of the chamber extend substantially up to the first non-permeable stratum and down to the second non-permeable stratum. Thereafter, a sufficient volume of fluid must first be extracted to create the desired pore space for disposal of fluid injection. The non-abandoned wells located within the chamber perimeter are considered a plurality of wellbores in communication with the surface for the extraction of fluid as well as a portion of these can also be used for the transmission of disposal fluid from the surface into the available pore space.

[00024] In another embodiment, the chamber can be located on property nearby a production facility which generates a disposable gas such as CO2. Once the chamber has been formed, a sufficient volume of fluid must first be extracted to create the desired pore space for disposal of fluid injection. This reduces the reservoir pressure within the chamber relative to the reservoir pressure outside. Therefore, one or more wells must be drilled to extract a portion of the fluid originally residing in the chamber before CO2 injection is commenced.

[00025] The wells used for construction of the partition sidewalls may thereafter be abandoned as those wells are incapable of fluid extraction or injection.

[00026] In the case of a CO2 sequestration chamber, the chamber could be created near the source of the generated CO2 and used to dispose of CO2 quickly and efficiently by well injection. Thus, CO2 can be sequestered at or near the source of emission. An added benefit is that this method of sequestration reduces costs associated with transportation and storage. Additionally, chambers may provide future offsets or reductions to any carbon tax scheme implemented by regulatory agencies. [00027] While it is well known to use proppants in combination with hydraulic fracturing to maintain a fracture and increase permeability, the method described herein is a hydro fracture grouting technique wherein a series of grout-filled panels, are formed in fissures created by hydro fracture pressure. The plurality of panels collectively define a vertical subsurface partition that inhibits movement of water from outside of the chamber to inside.

[00028] Panels are thus formed using horizontal drilling technology to first drill a well and set a casing string in the wellbore. The casing string has a lateral portion positioned in the desired fluid-containing stratum. The lateral portion of the casing string further comprises a plurality of pathways from the casing to the adjacent stratum, which are used to propagate vertical fissures and thereafter pump a sufficient volume of grout slurry into respective fissures created. A sufficient volume of grout slurry is a volume that would be necessary to create panels that would support a pressure drop across the panel and vertically extend to both the upper first non-permeable stratum as well as down to the lower second non-permeable stratum. A preferred volume range of grout slurry to be pumped into each fissure is between about 1,600-63,600 liters (10-400 barrels).

[00029] If the fluid-containing stratum is of such a depth that a single set of lateral portions is incapable of creating a partition which extends to both the first and second non- permeable stratums, then two or more sets of lateral portions at different true vertical depths could be utilized to ensure the sidewalls extend to both impermeable stratums.

[00030] Orientation of each hydraulically induced fissure or fracture is controlled by in- situ stress fields in the stratum adjacent to each pathway. Accordingly, because the depth of a sequestration chamber is at least 792 meters (2,600 ft), there is no present means to control the direction of each vertical fissure.

[00031] The grout partitions disclosed herein will inhibit water flow into the chamber or similarly impede CO2 from escaping the chamber.

[00032] In one preferred embodiment, the lateral portion of each side of the chamber is located at a depth which, upon hydraulic fracture, will propagate a vertical fracture up to the first non-permeable stratum as well as down to the second non-permeable stratum. A plurality of treatment sleeves are spaced apart in series at pre-determined intervals along the lateral. A panel is created by opening one sleeve and pumping a sufficient volume of a treatment fluid and grout slurry through the opened sleeve. After the grout slurry is pumped through the opened sleeve, the treatment sleeve is closed. This process is repeated until a grout slurry has been pumped through each of the treatment sleeves to be used to form respective grout panels.

[00033] Wells can also be used to drill lateral portions in different strata so that more than one chamber can be created, essentially one above the other, and separated by non- permeable strata.

[00034] Each panel of the grout partition for each respective sidewall of the chamber introduces a localized flow impediment that disrupts normal aquifer flow into the chamber. Aquifer water must travel a more tortuous path between the partition panels, thus inducing a flow restriction.

[00035] A less preferred alternative to treatment sleeves is the use of perforated holes in the casing for creating panels. Once the casing string has been run and cemented in place, the casing would be perforated at desired locations along the lateral portion, and thereafter, the treatment fluids and grout slurry would be pumped through the perforations for creating one or multiple panels. Once the treatment fluids and grout slurry have been pumped to create one or more panels, additional perforations are created up the casing string and the pumping process is repeated. While this alternative can create panels, it is not as consistent or predictable as the use of treatment sleeves. Holes can also be used to perforate the casing in combination with the use of treatment sleeves, for example, in the event of a malfunction of a treatment sleeve.

[00036] In one embodiment, a sequestration chamber would comprise: a) a plurality of subsurface partitions that define a perimeter around a predetermined volume of a fluidcontaining stratum and positioned between an upper non-permeable stratum and a lower non- permeable stratum. Within this volume would be available pore space that either exists, as in the case of a mature oil field; or, must first be extracted as would be the case for a stratum in its original state. One example would be a triangular prism in which three subsurface lateral portions are positioned to create respective partitions which collectively form substantially a triangular prism having non-permeable stratum as the ceiling face and a non-permeable stratum as the floor. Another example would be a square prism, having four subsurface lateral portions and respective non-permeable strata used as the ceiling and floor.

[00037] The sequestration chamber thus described can be part of a system for the underground storage of CO2. The system can comprise one or more chambers positioned either in the same fluid-containing stratum or comprise chambers at least partially vertically aligned within respective fluid containing stratum.

[00038] Subsurface partition technology can also extend the reach of existing hydrologic technology to control fluid flow or prevent the migration of contaminant plumes in the subsurface.

DESCRIPTION OF THE DRAWINGS

[00039] FIG. 1 is a prior art representation of a top view of an oilfiled.

[00040] FIG. 2 is a top view representation of the sequestration chamber area located within the oilfield represented in FIG. 1. [00041] FIG. 3 is a representation of downhole fluid extraction from the sequestration chamber.

[00042] FIG. 4 is a representation of disposal fluid injected into the sequestration chamber.

[00043] FIG. 5 illustrates a first alternative embodiment in which one sidewall of the sequestration chamber has two lateral portions with different true vertical depths to extend the sidewall to both a non-permeable roof stratum and a non-permeable stratum bottom.

[00044] FIG. 6 illustrates a second alternative embodiment in which sidewalls for two sequestration chambers, one above the other, are created from the same well.

[00045] FIG. 7 is a view of a plurality of wells 18 extending into chamber 100 between lateral portions 9 IL and 93L of FIG. 2.

[00046] FIG. 8 is a view of a lateral portion of a well 9 IL extending through a fluidcontaining stratum X having a plurality of treatment sleeves 54.

[00047] FIG. 9 is a view of the lateral portion of the well depicted in FIG. 8 having a panel 60 formed.

[00048] FIG. 10 is a view of the lateral portion of the well depicted in FIG. 8 having a plurality of panels 60 formed comprising a partition 10.

[00049] FIG. 11 is a representation of disposal fluid being injected into the sequestration chambers located in different fluid-containing stratum.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[00050] The figures presented herein are for illustrative purposes and are not necessarily shown in actual alignment, proportion or scale.

[00051] FIG. 2 represents an area of an oilfield selected with the perimeter of sequestration chamber 100 defined by lateral portions 91L-94L. FIGs 3-4 illustrate a completely artificially bounded sequestration chamber 100 having wells 18 from surface 12 extending through various strata 13 and the upper non-permeable stratum SI into the chamber.

[00052] A sequestration chamber 100 in the substantial shape of a square prism can be constructed beneath a pre-determined parcel of land under which lies a zone of connected pore space within a fluid-containing stratum X between first non-permeable stratum SI and a lower second non-permeable stratum S2. The minimum depth of stratum X is 792 meters (2,600 ft) true vertical depth. This depth is known to be the minimum depth for CO2 sequestration under most regulatory jurisdictions because it is the minimum depth at which the CO2 will remain in supercritical state under normal pressure conditions.

[00053] Besides the top and bottom defined by non-permeable stratums SI and S2, chamber 100 comprises sidewalls constructed from grout partitions 10 respectively formed from lateral portions 9 IL, 92L, 93L, and 94L of respective wells 91, 92, 93 and 94.

[00054] Multiple wells each having a lateral portion at a different depth can also constructed. FIG. 5 illustrates an embodiment in which well 91 is drilled having two lateral portions 9 IL and 9 IL’ in the same fluid-containing stratum X. A similar pair of lateral portions can be used for wells 92-94 for construction of a chamber 100 of square prism configuration which requires more than one lateral portion to create a sidewall from a pair of grout partitions 10 to extend up to SI and down to S2. This would depend upon the vertical height of the chamber and whether the panels 60 of each respective partition 10 would provide sufficient height to contact both the first non-permeable stratum S 1 and the lower second non-permeable stratum S2. [00055] FIG. 6 illustrates a scenario in which two sequestration chambers could be vertically positioned one above the other and separated by one or more non-permeable strata. Well 91 is drilled into two fluid containing strata X in which laterals 9 IL and 9 IL’ are positioned. The same configuration can be used for wells 92-94 for construction of a chamber 100 and a lower chamber 100’ as illustrated in FIG. 11. Chamber 100 being between non- permeable stratum SI and S2 and lower chamber 100’ being between non-permeable stratum S2 and S3.

[00056] FIG. 7 illustrates a plurality of wells 18 in which a portion of each wellbore is positioned within chamber 100 and is in communication with the surface for transmission of disposal fluid DF from the surface into the available pore space within the chamber.

[00057] The following describes the procedure for creation of a partition 10.

[00058] FIG. 8 illustrates a lateral portion 9 IL for well 91 which has been cemented using standard practice. Lateral portion 9 IL includes a plurality of spaced treatment sleeves 54 in the closed position. A surface array of tiltmeters (not shown) could be positioned to map the orientation and propagation for each panel created by the respective hydro fracture grouting treatments.

[00059] FIG. 9 illustrates the formation of a panel 60 from the end treatment sleeve. The sleeve is opened, and the adjacent stratum is hydraulically fractured.

[00060] The hydro fracture grouting treatment could comprise pumping fluids in the following quantity and order:

100 barrels Linear Gel;

100 barrels DFS-BGL; 50 barrels spacer fluid;

200 barrels, 13 pound per gallon (PPG) Class G & Type III cement; and, a sufficient volume of lease water to flush the casing string.

[00061] A 20 BPM pumping rate for all fluids could be implemented with a surface pressure sufficient to create a fissure in the fluid-containing stratum adjacent to the opened treatment sleeve 54.

[00062] FIG. 10 illustrates panels 60 formed from treatment sleeves 54 which collectively represent a grout partition 10 that is one sidewall for chamber 100.

[00063] Treatment sleeve spacing on each lateral portion would be based on the specific geologic properties. Because CO2 is to be sequestered within a chamber, government regulations may require dense spacing of panels 60. An additional consideration is that for each lateral portion, each panel created should have relatively the same orientation and size if the same volume of treatment fluid and grout slurry is used at a consistent downhole pumping pressure. This means the orientation of panels for one pair of partitions on opposing sides should be substantially perpendicular to their lateral portions while the other pair of opposing partitions will be substantially longitudinal. Thus, fewer panels may be required for one pair of opposing sides compared to the other pair.

[00064] Once all partitions 10 have been created, perimeter wells 91-94 can be abandoned with wells 18 converted for CO2 injection.

[00065] Fluid extraction is necessary prior to disposal operations. As illustrated in FIG. 3, a plurality of wells 18 would be drilled within sequestration chamber 100 being formed by wells 91-94. While only two wells 18 are shown, this is only for purposes of illustration and more wells can be utilized for purposes of extraction and injection. Wells 18 can be drilled to various depths as depicted in FIG. 7 within opposing panels 9 IL and 93L. After a sufficient volume of fluid F has been extracted as determined by the responsible government regulatory agency, wells 18 can be converted for injection of the CO2 disposal fluid DF as shown in FIG. 4.

[00066] Following a positive assessment of the integrity of partitions 10 making up the sidewalls of chamber 100, the amount of fluid F to be pumped from the chamber as shown in FIG. 3, would typically be determined by government regulation. Once a sufficient volume of fluid F has been removed from the pore space, typically demonstrated with pressure data from wells 18, the chamber will be determined to be isolated from the subsurface strata surrounding chamber 100. Injection of CO2 can then commence and continue until the chamber reaches a pre-determined maximum pressure at which point the sequestration chamber would be considered full and the wells 18 depicted in FIG. 4, would be capped and operations ended. During the injection phase, new wells could also be drilled to increase the injection rate of DF into chamber 100.

[00067] FIG. 11 illustrates a system in which CO2 sequestration chambers 100 and 100’ are formed in separate fluid-containing stratum X. Wells 18’ extend through chamber 100 and down into chamber 100’ such that injection of disposal fluid DF into wells 18’ will be discharged into chamber 100’.

[00068] Preferred embodiments of one aspect of the present invention will now be described by way of reference to the following clauses. l.A subsurface sequestration chamber comprising: a fluid-containing stratum having available pore space located within the perimeter established by the lateral portion of at least three wells, where the fluid-containing stratum is located beneath a first non-permeable stratum having a true vertical depth of at least 792 meters (2,600 ft) and above a second non-permeable stratum; and, a plurality of panels extending vertically from each lateral portion to the first non- permeable stratum and the second non-permeable stratum, each respective plurality of panels defining a sidewall.

2. The subsurface sequestration chamber of clause 1 further comprising a plurality of wellbores in communication with the surface for transmission of disposal fluid from the surface into the available pore space.

3. The subsurface sequestration chamber of clause 2 in which the disposal fluid is CO2.

4. A subsurface sequestration chamber comprising: a fluid-containing stratum having available pore space located within the perimeter established by an impermeable anticline and more than one lateral portion, where the fluidcontaining stratum is located beneath a first non-permeable stratum having a true vertical depth of at least 792 meters (2,600 ft) and above a second non-permeable stratum; and, a plurality of panels extending vertically from each lateral portion to the first non- permeable stratum and second non-permeable stratum, each respective plurality of panels defining a sidewall.

5. The subsurface sequestration chamber of clause 4 further comprising a plurality of wellbores in communication with the surface for transmission of disposal fluid from the surface into the available pore space.

6. In an oilfield having a plurality of wells that have extracted fluid from a fluid-containing stratum located beneath a first non-permeable stratum and above a second non-permeable stratum, the method for construction of a subsurface sequestration chamber comprising the steps of: identifying the location within a fluid-containing stratum for construction of the sequestration chamber; drilling a plurality of wells, each well having a lateral portion within the fluid containing stratum and where the lateral portions establish the perimeter of the chamber; and, forming a plurality of panels which extend vertically from each lateral portion to the first non-permeable stratum and the second non-permeable stratum, each respective plurality of panels defining a sidewall.

7. The method of clause 6 where the first non-permeable stratum has a true vertical depth of at least 792 meters (2,600 ft).

8. The method for construction of a subsurface sequestration chamber comprising the steps of: identifying the location within a fluid-containing stratum for construction of the sequestration chamber where the fluid-containing stratum is located beneath a first non- permeable stratum having a true vertical depth of at least 792 meters (2,600 ft) and above a second non-permeable stratum; drilling a plurality of wells, each well having a lateral portion within the fluid containing stratum and where the lateral portions establish the perimeter of the chamber; forming a plurality of panels which extend vertically from each lateral portion to the first non-permeable stratum and the second non-permeable stratum, each respective plurality of panels defining a sidewall; drilling a second plurality of wells, each well having sufficient depth for a portion of its wellbore to be located within the perimeter of the chamber; extracting fluid from the fluid-containing stratum using the second plurality of wells; determining when a sufficient volume of fluid has been extracted; and, converting at least a portion of the second plurality of wells for injection of a disposal fluid.

9. The method of clause 8 further comprising drilling at least one additional well having sufficient depth for a portion of its wellbore to be located within the perimeter of the chamber for injection of a disposal fluid.

10. The method of clause 8 further comprising the steps of: identifying a location within a second fluid-containing stratum for construction of a second sequestration chamber where the second fluid-containing stratum is located beneath the second non-permeable stratum and above a lower non-permeable stratum; and where the drilling a plurality of wells further comprises each well having a second lateral portion within the second fluid-containing stratum and where the second lateral portions establish the perimeter of the second sequestration chamber; forming a plurality of panels which extend vertically from each second lateral portion to the second non-permeable stratum and the lower non-permeable stratum, each respective plurality of panels defining a sidewall; and where at least a portion of the second plurality of wells have sufficient depth for a portion of its wellbore to be located within the perimeter of the second sequestration chamber.

1 l.The method of any of clauses 8, 9 and 10 where the disposal fluid is CO2.

12. A subsurface sequestration chamber 100 comprising: a fluid-containing stratum X having available pore space located within the perimeter established by grout partitions 10, where the fluid-containing stratum is located beneath a first non-permeable stratum SI having a true vertical depth of at least 792 meters (2,600 ft) and above a second non-permeable stratum S2; and where each of the sidewalls contact both the first non-permeable stratum and the second non-permeable stratum.

13. The subsurface sequestration chamber of clause 12 further comprising a plurality of wellbores 18 in communication with the surface 12 for transmission of disposal fluid DF from the surface into the available pore space.

14. A system for underground storage of CO2, the system comprising at least one sequestration chamber comprising: a fluid-containing stratum X having available pore space located within the perimeter established by sidewalls formed from grout partitions 10, where the fluid-containing stratum is located beneath a first non-permeable stratum having a true vertical depth of at least 792 meters (2,600 ft) and above a second non-permeable stratum; and where each of the sidewalls contact both the first non-permeable stratum and the second non-permeable stratum; and, a plurality of wells 18, each well having sufficient depth for a portion of its wellbore to be located within the perimeter of the chamber 100 in communication with the surface 12 for transmission of disposal fluid DF from the surface into the chamber.

[00069] The above embodiments are merely examples and are not intended to limit the disclosure, application, or use of the present invention.

Claims

1. A subsurface sequestration chamber comprising: a fluid-containing stratum having available pore space located within the perimeter established by the lateral portion of at least three wells, where the fluid-containing stratum is located beneath a first non-permeable stratum having a true vertical depth of at least 792 meters (2,600 ft) and above a second non-permeable stratum; and, a plurality of panels extending vertically from each lateral portion to the first non- permeable stratum and the second non-permeable stratum, each respective plurality of panels defining a sidewall.

2. The subsurface sequestration chamber of claim 1 further comprising a plurality of wellbores in communication with the surface for transmission of disposal fluid from the surface into the available pore space.

3. The subsurface sequestration chamber of claim 2 in which the disposal fluid is CO2.

5. The subsurface sequestration chamber of claim 4 further comprising a plurality of wellbores in communication with the surface for transmission of disposal fluid from the surface into the available pore space.

6. In an oilfield having a plurality of wells that have extracted fluid from a fluid-containing stratum located beneath a first non-permeable stratum and above a second non-permeable stratum, the method for construction of a subsurface sequestration chamber comprising the steps of identifying the location within a fluid-containing stratum for construction of the sequestration chamber; drilling a plurality of wells, each well having a lateral portion within the fluid containing stratum and where the lateral portions establish the perimeter of the chamber; and, forming a plurality of panels which extend vertically from each lateral portion to the first non-permeable stratum and the second non-permeable stratum, each respective plurality of panels defining a sidewall.

7. The method of claim 6 where the first non-permeable stratum has a true vertical depth of at least 792 meters (2,600 ft).

8. The method for construction of a subsurface sequestration chamber comprising the steps of identifying the location within a fluid-containing stratum for construction of the sequestration chamber where the fluid-containing stratum is located beneath a first non- permeable stratum having a true vertical depth of at least 792 meters (2,600 ft) and above a second non-permeable stratum; drilling a plurality of wells, each well having a lateral portion within the fluid containing stratum and where the lateral portions establish the perimeter of the chamber; forming a plurality of panels which extend vertically from each lateral portion to the first non-permeable stratum and the second non-permeable stratum, each respective plurality of panels defining a sidewall; drilling a second plurality of wells, each well having sufficient depth for a portion of its wellbore to be located within the perimeter of the chamber; extracting fluid from the fluid-containing stratum using the second plurality of wells; determining when a sufficient volume of fluid has been extracted; and, converting at least a portion of the second plurality of wells for injection of a disposal fluid.

9. The method of claim 8 further comprising drilling at least one additional well having sufficient depth for a portion of its wellbore to be located within the perimeter of the chamber for injection of a disposal fluid.

10. The method of claim 8 further comprising the steps of: identifying a location within a second fluid-containing stratum for construction of a second sequestration chamber where the second fluid-containing stratum is located beneath the second non-permeable stratum and above a lower non-permeable stratum; and where the drilling a plurality of wells further comprises each well having a second lateral portion within the second fluid-containing stratum and where the second lateral portions establish the perimeter of the second sequestration chamber; forming a plurality of panels which extend vertically from each second lateral portion to the second non-permeable stratum and the lower non-permeable stratum, each respective plurality of panels defining a sidewall; and where at least a portion of the second plurality of wells have sufficient depth for a portion of its wellbore to be located within the perimeter of the second sequestration chamber.

11. The method of any one of claims 8, 9 and 10 where the disposal fluid is CO2.

13. The subsurface sequestration chamber of claim 12 further comprising a plurality of wellbores 18 in communication with the surface 12 for transmission of disposal fluid DF from the surface into the available pore space.