Abstract: A method for storing CO2 includes identifying a depleted or partially depleted gas, gas condensate or oil reservoir having a plurality of injection wells and a plurality of production wells. The reservoir is then depleted. Once the reservoir is depleted or partially depleted, enhanced oil recovery and/or enhanced gas recovery is then performed on the reservoir where a first quantity of carbon dioxide is injected into the plurality of injection wells to displace the remaining oil and gas. Heat mining is then performed on the reservoir, where the second quantity of carbon dioxide is injected into the reservoir and the first and second quantities of carbon dioxide are subsequently produced to the surface for capture and conversion of geothermal heat of the first and second quantities of carbon dioxide into electricity. A third quantity of carbon dioxide is then injected and stored in the reservoir permanently.

Abstract: A CO2 sequestration system sequesters carbon dioxide as carbon dioxide hydrate in offshore saline aquifers. The system includes an offshore aquifer in a tropical region. A plurality of wellbores are positioned inside or around a perimeter of the aquifer. The CO2 may be injected into the aquifer via separate injectors located in the wellbores connected to the aquifer while aquifer water or brine is produced from one or more of the other wellbores and provided to the aquifer. Injection of the CO2 into and production of water from the offshore aquifer at separately timed intervals may maintain the reservoir pressure below the reservoir fracture pressure and the hydrate formation pressure so that the CO2 may be stored as carbon dioxide hydrate within the aquifer. Depending on the specific output desired, the aquifer may be positioned either straddling or within a hydrate stability zone. A method for sequestering CO2 uses the aforementioned system to carry out CO2 sequestration.

Abstract: A CO2 sequestration system sequesters carbon dioxide as carbon dioxide hydrate in offshore saline aquifers. The system includes an offshore aquifer in a tropical region. A plurality of wellbores are positioned inside or around a perimeter of the aquifer. The CO2 may be injected into the aquifer via separate injectors located in the wellbores connected to the aquifer while aquifer water or brine is produced from one or more of the other wellbores and provided to the aquifer. Injection of the CO2 into and production of water from the offshore aquifer at separately timed intervals may maintain the reservoir pressure below the reservoir fracture pressure and the hydrate formation pressure so that the CO2 may be stored as carbon dioxide hydrate within the aquifer. Depending on the specific output desired, the aquifer may be positioned either straddling or within a hydrate stability zone. A method for sequestering CO2 uses the aforementioned system to carry out CO2 sequestration.

Abstract: An offshore oil production system, comprising a structure in a body of water, having a portion extending above a surface of the body of water; a wellhead located at a boom of the body of water; a riser extending from the wellhead to the portion extending above the surface; a primary wellbore extending into a subsea formation beneath the body of water; and at least two secondary wellbores extending further into the subsea formation beneath the body of water and beneath the primary wellbore.

Abstract: An offshore oil production system, comprising a structure in a body of water, having a portion extending above a surface of the body of water; a first surface wellhead located at a top of the body of water; a second surface wellhead located at a top of the body of water; a first wellhead located at a bottom of the body of water; a second wellhead located at a bottom of the body of water; a first riser extending from the first wellhead to the first surface wellhead; and a second riser extending from the second wellhead to the second surface wellhead; wherein the first surface wellhead is a distance of less than about 12 feet from the second surface wellhead.

Abstract: An offshore oil production system, comprising a structure in a body of water, having a portion extending above a surface of the body of water; a wellhead located at a boom of the body of water; a riser extending from the wellhead to the portion extending above the surface; a primary wellbore extending into a subsea formation beneath the body of water; and at least two secondary wellbores extending further into the subsea formation beneath the body of water and beneath the primary wellbore.

Abstract: An offshore oil production system, comprising a structure in a body of water, having a portion extending above a surface of the body of water; a surface wellhead located at a top of the body of water; a first wellhead located at a bottom of the body of water; a second wellhead located at a bottom of the body of water; a first riser extending from the first wellhead to the surface wellhead; and a second riser extending from the second wellhead to the surface wellhead.

Abstract: Polymers used to prevent fluid loss from boreholes may be eliminated after a predetermined time by including with the polymer composition halogen-substituted organic acids or their salt derivatives. These components hydrolyze, releasing hydrogen-halogen acids which break down the polymers within the wellbore or formation.

Abstract: Improved gas foam flooding surfactants and gas foam-forming mixtures wherein the surfactants are enriched in olefin disulfonate. The surfactants may be used in either a gas drive or a gas soak process. Use of the disulfonate-enriched gas foam surfactants and mixtures in a gas flooding operation is also described.

Abstract: An improved process for recovering oil by injecting a mixture of noncondensible gas and gas foam surfactant into an oil-containing subterranean reservoir, the improvement provided by using a surfactant enriched in olefin disulfonate. The sulfactant may be used in either a gas drive or a gas soak process. Disulfonate-enriched gas foam surfactants and mixtures are also described.

Abstract: Oil is produced from an ion-exchanging reservoir by a dual gradient-establishing injection of a relatively short and concentrated slug of hot aqueous fluid containing surfactant and monovalent salt, followed by a steam-foaming mixture in which stem is mixed with much less of each of the surfactant and salt.

Abstract: Zinc oxide and zirconium oxide are used as weighting materials for water and oil based drilling fluids for horizontal wells.