Abstract: A method for selective placement, initiation and propagation of a hydraulically induced fracture in an open wellbore.

Abstract: Apparatus and methods for recovering and using geothermal energy. Such methods include at least partially vaporizing a working fluid by passing it through a flow loop that at least partially extends into a heated subterranean zone and employing the vaporized working fluid to power a turbine. At least a portion of the flow loop can comprise a depleted or partially depleted hydrocarbon well.

Abstract: Methods and systems are provided for favorably altering the chemomechanical properties of subterranean formations using treatment fluids comprising surfactants and halide salts. Methods for treating formations comprise the steps of introducing a chemomechanical treatment fluid into the formation and allowing the treatment fluid to interact with the formation to alter its petrochemical properties in various ways. Depending on the application, the chemomechanical treatment fluid may comprise a base fluid, a halide salt and an amphoteric or nonamphoteric surfactant where the surfactant is dissolved in the base fluid at a concentration below its critical micelle concentration. Applications of use involving the chemomechanical treatment fluids include treatment operations, secondary recovery operations, drilling operations, and any other operation that would benefit from the formation property modifications described herein.

Abstract: A method for selective placement, initiation and propagation of a hydraulically induced fracture in an open wellbore.

Abstract: Apparatus and methods for recovering and using geothermal energy. Such methods include at least partially vaporizing a working fluid by passing it through a flow loop that at least partially extends into a heated subterranean zone and employing the vaporized working fluid to power a turbine. At least a portion of the flow loop can comprise a depleted or partially depleted hydrocarbon well.

Abstract: A method for resistively heating a subterranean region to lower the viscosity of heavy oil by using production tubing coupled to at least two electrodes modified for three-phase flow and an electrically insulating body.

Abstract: A method for enhancing the productivity of a subterranean well comprising passing a solvent out of a string of production casing through perforations proximate an unfractured soluble formation, dissolving a region of the soluble formation to create a cavity therein, and increasing the size of the cavity until the subterranean formation proximate the cavity collapses.

Abstract: A method for enhancing the productivity of a subterranean well comprising passing a solvent out of a string of production casing through perforations proximate an unfractured soluble formation, dissolving a region of the soluble formation to create a cavity therein, and increasing the size of the cavity until the subterranean formation proximate the cavity collapses.

Abstract: A method for forming a fracture in a viscous oil subterranean formation wherein a data-fracturing operation is carried out to first determine the “leak-off” rate for the formation and then the formation is fractured with a slurry wherein the liquid from the slurry will leak into the formation at the predetermined leak-off rate to thereby provide fractures of a desired length necessary in sand control or the like. In accordance with the present invention, the formation is treated before both the data-fracturing operation and the subsequent fracturing operation with a treatment fluid (e.g. diesel) which will interact with the viscous oil to reduce its viscosity so that the fracturing fluid can readily leak into the formation.

Abstract: A gas hydrate formation is treated by horizontally fracturing the formation, placing electrically conductive proppant particles in the fracture, and passing an electric current through the proppant particles in the fracture to generate sufficient heat to release gas from the hydrate. The method has particular application in shallow gas-bearing formations underlying or within the permafrost.

Abstract: A method for fracturing a horizontal well at a plurality of locations along the length of the horizontal portion of the well by plugging previously fractured downstream fracture zones with a mixture of a proppant and a slump-inhibiting material.

Abstract: A method for stimulating a wellbore penetrating a solid carbonaceous subterranean formation by positioning a hydrajet in an uncased portion of the wellbore penetrating the formation; perforating the formation with the hydrajet; and producing carbonaceous fluids and particulates from the formation through the wellbore and, thereby, forming a cavity in the formation surrounding the wellbore.

Abstract: A method for fracturing a plurality of different subterranean production zones which are spaced along a wellbore wherein flow is established into a first or lower zone while a removable sleeve blocks flow into the other upper zones. The first zone is fractured and the sleeve is then notched, preforated, or repositioned to establish flow into a second zone while flow is now blocked into the lower, fractured zone. The second zone is fractured and this procedure is repeated until all of the desired zones have been fractured after the sleeve is retrieved to the surface.

Abstract: According to the present invention, the production of petroleum from a petroleum-bearing subterranean formation penetrated by a wellbore is accomplished by (a) fracturing the subterranean formation and injecting a conductive proppant into the fracture, the conductive proppant comprising particles which are at least partially coated with a heat hardenable, conductive resin to create a fluidly and electrically conductive fracture in the formation; (b) passing an electrical current into the formation through the wellbore to heat the formation and harden the conductive resin thereby at least partially aggregating the particles and retaining the particles in the fracture and heating the fracture and the subterranean formation in the vicinity of the fracture.

Abstract: A method for determining the minimum length for a fracture in a fluid-producing formation to control the production of sand therefrom wherein a plurality of critical drawdown pressures are calculated from known formation data which correspond to a plurality of different, estimated respective fracture lengths. Once the critical drawdown pressures for the reservoir are correlated with their corresponding fracture lengths, a critical drawdown curve for that particular reservoir is established. Additional sets of curves are generated from known data which when overlaid with the critical drawdown pressure curve allows a minimum length of fracture to be selected which will produce the formation at a given rate at a prescribed drawdown pressure without producing any substantial amounts of sand from the formation.

Abstract: An improved method for stimulating coal degasification wells comprising the injection of a foam into a coal seam which contains natural or induced fractures. Thereafter, high pressure gas is injected into the coal seam and suddenly released to cause disintegration of coal surrounding the borehole.

Abstract: A system and method for matrix stimulation field monitoring providing real time control, optimization and post job evaluation of matrix treatments is disclosed herein. Using calculated or measured bottom hole pressures or coil tubing reflective pressures, the system and method predicts pre-treatment damage or skin from a step rate test, then shows the evolution of skin removal versus treating fluid volume in real time. The method and system provides real time information about diverter use, treatment height, damage radius and other important well parameters.

Abstract: An improved method for stimulating coal degasification wells comprising the use of a coal comminuting solvent to weaken the cleat structure of a coal seam immediately prior to use of high pressure gas in a gas cavitation process. A solvent such as ammonia is injected into the coal seam and allowed to dissolve materials from the cleat structure for a period of time sufficient to weaken that structure. Thereafter, high pressure gas is injected into the coal seam and suddenly released to cause disintegration of coal surrounding the borehole.

Abstract: A cavity induced stimulation method for improving the initial production of fluids, e.g. methane, from a coal seam. A well is drilled and completed into the seam. A tubing string is run into the hole and liquid CO.sub.2 is pumped down tubing while a backpressure is maintained on the well annulus. Pumping is stopped and the pressure is allowed to build until it reaches a desired elevated pressure (e.g. 1500 to 2000 psia). The pressure is then quickly released. The sudden release of pressure plus other factors cause the coal to fail and fragment into particles. The particles are removed to form a cavity in the seam. The above steps may be repeated until the desired cavitation is achieved.

Abstract: Coal and other particulate can be transported on a conveyor belt exposed to winter weather conditions with reduced slippage of the particulate on the belt surface by periodically treating the belt surface with from about 0.001 to about 0.005 gallons per square foot of belt surface (0.04-0.4 liters/sq. meter) of a composition containing a small amount of a dimethyl polysiloxane with the balance consisting substantially of water soluble components comprising (A) a water soluble polyhydroxy compound or monoalkyl ether thereof, and (B) a water soluble organic nonvolatile compound having at least one hydrophilic group, (A) being different from (B).