Abstract: Method for identifying, determining and correcting source-related phase errors in data from a controlled source electromagnetic survey by using data from ordinary survey receivers, i.e. without benefit of source monitoring data. Abrupt anomalies indicating source malfunctions are identified (71) in the time domain by plotting time intervals between neighboring zero crossings or by zero-lag cross correlation between consecutive bins of receiver data, and the amount of the time error (73) can be determined by performing cross correlation between two bins on either side of an anomaly. In the frequency domain, transmitter anomalies can be identified by looking for discontinuities in plots of phase vs. offset, and the corrective phase shift can be determined by matching the phase on one side of the anomaly to that on the other side. A global time/phase shift (76) can be determined by using phase frequency-scaling behavior at near offsets.

Abstract: Method for reducing the time needed to perform geophysical inversion by using simultaneous encoded sources in the simulation steps of the inversion process. The geophysical survey data are prepared by encoding (3) a group of source gathers (1), using for each gather a different encoding signature selected from a set (2) of non-equivalent encoding signatures. Then, the encoded gathers are summed (4) by summing all traces corresponding to the same receiver from each gather, resulting in a simultaneous encoded gather. (Alternatively, the geophysical data are acquired from simultaneously encoded sources.) The simulation steps needed for inversion are then calculated using a particular assumed velocity (or other physical property) model (5) and simultaneously activated encoded sources using the same encoding scheme used on the measured data. The result is an updated physical properties model (6) that may be further updated (7) by additional iterations.

Abstract: One or more techniques for determining time-varying stress and strain fields within a subsurface region include integrating a seismic model (110) of a reservoir within the subsurface region with a geomechanical model (140) of the subsurface region. An estimate of the time-varying stress and strain fields within the subsurface region during production of the reservoir are determined, wherein the estimate is based on the integration of the seismic model with the geomechanical model. The integration of the seismic model with the geomechanical model can be used to predict the feasibility of passive seismic monitoring for a reservoir within a subsurface region (170).

Abstract: Methods and systems for removing nitrogen from a natural gas feed stream. The systems and methods generally include a heat exchange unit, a separation unit, and a liquid methane pump unit, where the separation unit produces a liquid methane bottoms stream and a gaseous overhead stream enriched in nitrogen and the liquid methane pump unit compresses the liquid methane bottoms stream and then pumps the stream through the heat exchange unit to cool a natural gas feed stream. In some embodiments the liquid methane pump unit is a sleeve bearing type unit. Beneficially, the disclosed systems and methods incorporate high head pumps for liquid methane compression instead of vaporizing the liquid methane and compressing it in a gaseous compression units that are typically used for this purpose, saving space, materials, and power.

Abstract: A method is disclosed for simulating the formation of sedimentary deposits. In one embodiment, this method involves, (a) solving a two-dimensional time-dependent map view system of equations for at least flow momentum, flow height, suspended sediment concentration, and entrainment of overlying water, (b) calculating net sediment deposition at each map view location using the flow properties, (c) recording the time-variability of the net sediment deposition.

Abstract: A method of lowering the temperature of a subsurface formation, e.g., comprising oil shale, includes injecting a cooling fluid under pressure into a wellbore. The wellbore is completed at or below a depth of the subsurface formation, and the wellbore includes a bore formed through the subsurface formation defining a diameter. The cooling fluid comprises a slurry having particles of frozen material. The cooling fluid is circulated across the formation in order to lower the temperature of at least a portion of the formation to a point that is at or below the freezing point of water.

Abstract: An improved method of producing hydrocarbons from a subterranean formation in which a solids-stabilized emulsion (SSE) is formed, the SSE comprising oil as a first liquid, droplets of a second liquid suspended in the oil, and solid particles that are insoluble in both the oil and the second liquid at the conditions of the subterranean formation. The SSE with dissolved gas is injected into the subterranean formation as a drive fluid, and at least a portion of the SSE is placed into one or more area of the subterranean formation having an in situ pressure sufficiently lower than the selected partial pressure to permit evolution of at least a portion of the gas from the oil. Furthermore, a method of making the foamy SSE is also provided.

Abstract: A process for the separation of production fluids is provided. The production fluids comprise an oil/water emulsion stabilized with fine solids. The emulsion may further comprise asphaltenes and naphthenic acids and resins. The process includes subjecting the emulsion to a flocculating agent to flocculate solids within the emulsion, and separating water and solids from crude oil in a first separator. The process further includes subjecting the separated crude oil to a demulsifier after subjecting the emulsion to a flocculating agent, and further separating water from the crude oil in a second separator. A process for producing fluids from a hydrocarbon-bearing reservoir is also provided, using the separation processes herein.

Abstract: Techniques are disclosed for performing time-lapse monitor surveys with sparsely sampled monitor data sets (11). An accurate 3D representation (e.g., image) of a target area (e.g., a hydrocarbon bearing subsurface reservoir) is constructed using the sparsely sampled monitor data set (e.g., seismic data set). The sparsely sampled monitor data set may be so limited that it alone is insufficient to generate an accurate 3D representation of the target area, but accuracy is achieved through use of certain external information (14). The external information may include predetermined base survey data from a first time that is used (12) to interpolate data that is not recorded in the sparsely sampled monitor data set to derive a fully sampled monitor data set that can be processed (e.g., using conventional processing techniques) for determining an accurate representation of the target area at a second time.

Abstract: A method of demulsifying a water-in-oil emulsion is provided. The method includes treating a volume of fluids comprising oil and water by adding a salt of a polynuclear, aromatic sulfonic acid to the fluids so as to cause the oil and water to be at least partially demulsified. The method may further include separating water and oil in a separator. A method of producing hydrocarbons from a subsurface reservoir is also provided. The hydrocarbons include a water-in-oil emulsion. The method includes producing the hydrocarbons through a wellbore, and subjecting the water-in-oil emulsion to a salt of a polynuclear, aromatic sulfonic acid additive so as to cause the oil and water to be at least partially demulsified.

Abstract: A compressible object is described that may be utilized in drilling mud and with a drilling system to manage the density of the drilling mud. The compressible object includes a shell that encloses an interior region. Also, the compressible object has an internal pressure (i) greater than about 200 pounds per square inch at atmospheric pressure and (ii) selected for a predetermined external pressure, wherein external pressures that exceed the internal pressure reduce the volume of the compressible object and wherein the shell being designed to reduce localized strains of the compressible object during expansion and compression of the compressible object.

Abstract: A method for heating a subsurface formation using electrical resistance heating is provided. In one aspect, the method includes creating a passage in the subsurface formation between a first wellbore located at least partially within the subsurface formation, and a second wellbore also located at least partially within the subsurface formation. An electrically conductive granular material is placed into the passage so as to provide electrical communication between the first wellbore and the second wellbore. Electrically conductive members are provided in the first wellbore and second wellbore so as to form an electrically conductive flow path comprised of the electrically conductive members, the granular material, and a power source. An electrical current is established through the electrically conductive flow path, thereby resistively heating at least a portion of the conductive members which in turn heats the subsurface formation.

Abstract: A compressible object is described that may be utilized in drilling mud and with a drilling system to manage the density of the drilling mud. The compressible object includes a shell that encloses an interior region. The interior region of the shell is at least partially filled with a foam. The internal pressure of the compressible object may be greater than about 200 psi (pounds per square inch) at atmospheric pressure, greater than 500 psi at atmospheric pressure, greater than 1500 psi at atmospheric pressure or more preferably greater than 2000 psi at atmospheric pressure.

Abstract: The method for suppressing noise in the controlled seismic source electromagnetic survey data based on the frequency content of the noise (51) contained in the data. The invention recognizes that some data variations across bins cannot be attributed to resistivity variations within the earth. This variation across the bins constitutes a model of noise in such surveys, and the invention mitigates noise that obeys this model.

Abstract: A method for developing hydrocarbons from a subsurface formation. The subsurface formation may include oil shale. The method may include conductively heating portions of an organic-rich rock formation located in a development area, thereby pyrolyzing at least a portion of formation hydrocarbons located in a heated zone in the organic-rich rock formation into hydrocarbon fluids. The heat may be generated from one or more wellbores completed within the formation, such as by means of a resistive heating element. At least one unheated zone is preserved within the organic-rich rock formation. This leaves a portion of the development area substantially unpyrolyzed. The at least one unheated zone is sized or configured in order to substantially optimize that portion of the development area in which the organic-rich rock is pyrolyzed while controlling subsidence above the organic-rich rock formation.

Abstract: A method and apparatus for storing liquid within a storage tank such that a natural resonance of fluid motion of the stored fluid falls between natural resonance periods of a floating vessel that includes the storage tank. As a result, resonant energy of the floating vessel imparted to fluid stored in the storage tank may be controlled and sloshing loads may be reduced, thereby avoiding damage to the floating vessel.

Abstract: This invention relates generally to a method of simulating the signal of an electromagnetic source using one or more dipole sources. In the method a dipole source is located at an excitation location corresponding to a segment of the electromagnetic source to be simulated. The dipole source is activated, and an electromagnetic signal recorded at one or more receiver locations. This process is repeated for additional excitation locations corresponding to additional segments of the electromagnetic source. The data from the sequence of dipole source excitation locations is processed to determine the simulated signal of the electromagnetic source.

Abstract: A compressible object is described that may be utilized in drilling mud and with a drilling system to manage the density of the drilling mud. The compressible object includes a shell that encloses an interior region. The shell experiences less strain when the external pressure is about equal to the internal pressure than when the external pressure is above or below a predetermined compression interval of the compressible object includes a shell that encloses an interior region.

Abstract: Method is provided for simulating a physical process such as fluid flow in porous media by performing a fine-grid calculation of the process in a medium and re-using the fine grid solution in subsequent coarse-grid calculations. For fluid flow in subsurface formations, the method may be applied to optimize upscaled calculation grids formed from geologic models. The method decreases the cost of optimizing a grid to simulate a physical process that is mathematically described by the diffusion equation.

Abstract: A method is disclosed for combining seismic data sets. This method has application in merging data sets of different vintages, merging data sets collected using different acquisition technologies, and merging data sets acquired using different types of sensors, for example merging hydrophone and geophone measurements in ocean bottom seismic data.