Abstract: The disclosed invention provides a method for recovering hydrocarbons from a subterranean formation by injecting an emulsion, comprising oil and water, into the formation. More specifically, the emulsion is stabilized using undissolved solid particles, which are preferably at least partially oleophilic. The solids-stabilized emulsion may be used either as a drive fluid for displacing hydrocarbons from the formation or to produce a barrier for diverting flow of fluids in the formation. Such solid particles may be either formation solid particles (i.e., indigenous to the formation) or nonformation solid particles (i.e., obtained from outside the formation). Nonformation solid particles may either be naturally occurring or synthetic. Some preferred solids include clays, quartz, feldspar, gypsum, coal dust, asphaltenes, and polymers.

Abstract: Apparatus and method for determining the location of the source of seismic energy around a well are provided. Multiple seismic receivers, each receiver having orthogonal seismic sensors, are axially spaced on a tool which is capable of sending real-time seismic signals to the surface. A method for calculating the location with respect to the receivers is also provided.

Abstract: The disclosed invention is a solids-stabilized emulsion and method for making same for use in recovering hydrocarbons from a subterranean formation. More specifically, the emulsion comprises oil and water and is stabilized using undissolved solid particles, which are preferably at least partially oleophilic. Carbon dioxide or another gas is added to the emulsion to adjust the emulsion's viscosity to the desired level. The solids-stabilized emulsion may be used either as a drive fluid for displacing hydrocarbons from the formation or to produce a barrier for diverting flow of fluids in the formation. Such solid particles may be either formation solid particles (i.e., indigenous to the formation) or nonformation solid particles (i.e., obtained from outside the formation). Nonformation solid particles may either be naturally occurring or synthetic. Some preferred solids include clays, quartz, feldspar, gypsum, coal dust, asphaltenes, and polymers.

Abstract: A novel method of determining the probability that a planned drilling path will collide with an existing wellbore is disclosed. The method utilizes available uncertainty information to determine a probability for each of a plurality of segments of the planned drilling path that a projection of the segment onto a plane will intersect a projection of a corresponding segment of the existing wellbore onto the plane. The method of this invention then determines the net probability for each segment of the planned drilling path that the segment will intersect the corresponding segment of the existing wellbore by taking into account the effect of constraints imposed on each segment, by adjacent segments. The probability that the planned drilling path will intersect the existing wellbore is determined by adding together all of the net probabilities.

Abstract: A method for inhibiting the formation and/or agglomeration of clathrate hydrates in a petroleum fluid stream containing water is disclosed. The disclosed method uses predetermined inhibitors having a guest group, a polymer backbone, and an anchor group positioned between the guest group and the polymer backbone. The inhibitor predetermination method comprises selection of the polymer backbone, anchor group and guest group using several types of criteria. The polymer backbone should produce a substantially water soluble polymer in combination with the anchor group and the guest group. The anchor group should be a hydrophilic moiety with between one and four hydrogen bonding atoms. The guest group should be either a hydrophobic or amphiphilic moiety with a carbon atom to heteroatom ratio greater than or equal to about two to one and an average van der Waals diameter between about 3.8 angstroms and about 8.6 angstroms.

Abstract: A method for stimulating production from wells drilled into natural gas reservoirs characterized by lenticular deposits. The reservoir thickness through which the wells are drilled is divided into multi-stage zones that are further divided into single-stage zones. Each single-stage zone is perforated and then fractured. The fracturing is conducted in multiple stages to sequentially fracture each of the single-stage zones within a multi-stage zone; the fracturing stages being separated by ball sealers. Well spacing may also be controlled to match fracture drainage and size of the lenticular deposits.

Abstract: A method for quantitatively measuring lateral continuity at a specified subsurface location from seismic data. The seismic data trace nearest to the specified location is designated as the reference trace. Next, all data traces falling within a specified distance from the reference trace are extracted from the data, and one or more statistics which measure the similarity between each trace and the reference trace are calculated. Only the portions of the traces falling within the target formation are considered. Preferably, the statistics should permit comparison of both the temporal and atemporal behaviors of the traces. The results are compared to objective significance tests to determine whether each trace is the same as or different from the reference trace.

Abstract: Method and apparatus are provided for a new type of geophysical prospecting. The method applies an electric field to a fluid-containing porous subsurface formation to create a fluid pulse from changes in the polarization of pore fluid dipoles. The fluid pulse propagates in the subsurface as a seismic wave that may be detected by an appropriate array of seismic detectors. The apparatus is a pulsed DC or AC source for generating an applied electric field and a seismic detector.

Abstract: A method for inhibiting the formation of clathrate hydrates in a fluid having hydrate forming constituents is disclosed. More specifically, the method can be used in treating a petroleum fluid stream such as natural gas conveyed in a pipe to inhibit the formation of a hydrate restriction in the pipe. The hydrate inhibitor used for practicing the method is selected from the family of substantially water soluble copolymers formed from N-methyl-N-vinylacetamide (VIMA) and one of three comonomers, vinylpyrrolidone (VP), vinylpiperidone (VPip), or vinylcaprolactam (VCap). VIMA/VCap is the preferred copolymer. These copolymers may be used alone or in combination with each other or other hydrate inhibitors. Preferably, a solvent, such as water, brine, alcohol, or mixtures thereof, is used to produce an inhibitor solution or mixture to facilitate treatment of the petroleum fluid stream.

Abstract: The invention described here is a method for using produced fluid compositions to decide how to modify injection/production strategies in oil recovery processes that involve injection of non-aqueous recovery agents ("Injectant"). The procedure is based on the premise that once a given zone is swept by injectant, most subsequent hydrocarbon recovery from that zone will occur by vaporization or extraction into the injectant. Because only the most volatile hydrocarbon components can be extracted, hydrocarbons produced by displacement can be distinguished from those produced by extraction by examining the hydrocarbon composition. Heavy, non-volatile components are recovered only by displacement. The disclosed method determines quantities of displaced vs. extracted hydrocarbons by comparing the produced hydrocarbon composition to that of the original in-place oil. Such information may be used to modify operations in order to most effectively use injectant to recover hydrocarbons from the reservoir.

Abstract: Computer-implemented methods of processing seismic data for the purpose of suppression of multiple reflections, or multiples, are subjected to quantitative evaluation. The evaluation is done by a computerized testing procedure. A known earth model is formed. From this model, data composed of primary reflections only, and data containing multiple reflections only are generated. These are retained separately, but a third data set representing their sum is also formed to serve as an original data set for processing. The original data set or sum is then processed by the processing method being evaluated. The processed results are then decomposed by a time-varying, least squares technique into primaries-only and multiples-only components. The decomposed primaries-only and multiples-only components so formed are then compared against the values of the original sets from the known earth model.

Abstract: The disclosed invention provides a method for recovering hydrocarbons from a subterranean formation by injecting an emulsion, comprising oil and water, into the formation. More specifically, the emulsion is stabilized using undissolved solid particles, which are preferably at least partially oleophilic. The solids-stabilized emulsion may be used either as a drive fluid for displacing hydrocarbons from the formation or to produce a barrier for diverting flow of fluids in the formation. Such solid particles may be either formation solid particles (i.e., indigenous to the formation) or nonformation solid particles (i.e., obtained from outside the formation). Nonformation solid particles may either be naturally occurring or synthetic. Some preferred solids include clays, quartz, feldspar, gypsum, coal dust, asphaltenes, and polymers. Carbon dioxide or another gas may be added to the emulsion to adjust the emulsion's viscosity to the desired level.

Abstract: A method for analyzing seismic intervals and predicting subsurface petrophysical properties through the use of a new set of attributes known as Linear Shape Attributes (LSAs). The Linear Shapes form an orthogonal basis set derived directly from the seismic data traces for the interval in question. Collectively, the LSAs capture substantially all of the useful information contained in the input data set. The input data set may include all or a selected portion of the seismic data traces for the prospect. Petrophysical information obtained from well logs and/or pseudo-well logs may be used to calibrate the LSAs. The calibrated LSAs may then be used for a variety of purposes, such as predicting subsurface petrophysical properties at other locations or determining the location of a new well.

Abstract: This invention is directed toward a method for inhibiting the formation (nucleation, growth and agglomeration) of clathrate hydrates. The method comprises adding into a mixture comprising hydrate forming substituents and water, an effective amount of a hydrate inhibitor selected from the group consisting of anionic, cationic, non-ionic and zwitterionic hydrate inhibitors. The hydrate inhibitor has a polar head group and a nonpolar tail group not exceeding 12 carbon atoms in the longest carbon chain.

Abstract: Features of subsurface earth reservoirs of interest are made available for analysis and evaluation by forming three-dimensional, geologic block models based on field data. The field data include geological observations, such as lithofacies and porosity values obtained from well data and other sources, as well as geophysical data, usually from seismic surveys. The geologic models representative of subsurface reservoirs so obtained are optimized to match as closely as feasible geologic constraints known or derived from observed geologic data. The models also conform to geophysically based constraints indicated by seismic survey data. The modeled geologic lithofacies and porosity are converted into acoustic velocity and bulk density values, which are then formulated as a seismic response which is then compared with actual seismic data.

Abstract: Computer-implemented methods of processing and imaging seismic data by migration and DMO (dip moveout) are subjected to quantitative evaluation. The evaluation is done by a computerized testing procedure. An impulse data set is formed containing a single "live" trace and zero amplitudes for other traces. A selected velocity function is also generated. The impulse data set is then processed by the processing method being evaluated. Estimates of the vertical traveltime, amplitude and phase along each of the impulse-response events are then generated. The estimates so formed are compared against exact values obtained from a model using an integral equation which accurately describes migration or DMO. Users thus are provided with indications of how the processing techniques may be expected to perform on real data.

Abstract: A method of geophysical prospecting using seismic trace attribute analysis for formation characterization. More particularly, a method for selection of seismic traces which most accurately represent the subsurface formation in the area of a seismic survey is disclosed. In one embodiment, inflection-point interval analysis is used to account for effects of local surfaces.

Abstract: A method for attenuating source-generated surface wavetrains in a set of seismic data traces. According to the method, the seismic data traces are Fourier transformed with respect to time to determine the frequency components of the surface wavetrain. A phase matching operation is then performed using estimates of the wavenumbers for each of the frequency components to approximately align the surface wavetrain in the seismic data traces. Next, a spatial low-pass filter is used to remove the approximately aligned surface wavetrain. Finally, the phase matching is removed and an inverse Fourier transformation is performed to return the seismic data traces to the time domain.

Abstract: Apparatus and method for determining the location of the source of seismic energy around a well are provided. Multiple seismic receivers, each receiver having orthogonal seismic sensors, are axially spaced on a tool which is capable of sending real-time seismic signals to the surface over conventional wireline. A method for calculating the location with respect to the receivers is also provided, the method employing data from all the sensors and a performance function to minimize error in the determination of location, and a simplified method is provided for determining if a fracture has extended past a selected depth in a formation.

Abstract: A method for inhibiting the formation of clathrate hydrates in a fluid having hydrate forming constituents is disclosed. More specifically, the method can be used in treating a petroleum fluid stream such as natural gas conveyed in a pipe to inhibit the formation of a hydrate restriction in the pipe. The method uses a mixture comprising a first additive and a second additive. The mixture produces a synergistic hydrate inhibition effect. The first additive is selected from the class of substantially water soluble polymers. The second additive is selected from the class of ionic or non-ionic organic compounds which have a polar part and nonpolar part with the nonpolar part having an alkyl, alkenyl, or alkynyl group with 12 or fewer carbon atoms.