Abstract: Methods are provided for tracking carbon dioxide (CO2) migration in a hydrocarbon-bearing reservoir located under a cap rock in a formation. In one embodiment, at least one seismic source and a plurality of receivers are located in spaced boreholes in the formation with the sources and receivers located near or at the reservoir so that direct paths from the sources to the receivers extend through the reservoir. CO2 is injected from the borehole containing the seismic sources into the reservoir, and the sources are activated multiple times over days and seismic signals are detected at the receivers. From the detected signals, time-lapse travel delay of direct arrivals of the signals are found and are used to track CO2 in the reservoir as a function of time. In another embodiment, the sources and receivers are located above the reservoir, and reflected waves are utilized to track the CO2.

Abstract: Embodiments include constructing a reservoir model of an earth formation. The method may also include selecting a predetermined set of fundamental parameters to describe the earth formation and assigning initial values for the predetermined set of fundamental parameters for each of the plurality of layers. The method may include using the initial values for each of the plurality of layers. The method may include computing physical-response-relevant properties as a function of space and time for each of the plurality of layers using the solutions and then computing tool responses using the physical-response-relevant properties. The method may include installing an electrode array between an insulation portion of a metal casing provided in a borehole and a physical formation and obtaining formation measurement information from the electrode array, comparing the formation measurement information to the computed tool response to obtain an error signal and modifying the initial values in an iterative process.

Abstract: Methods and apparatus are provided for the measurement of the compressibility of reservoir fluid. A piezoelectric material is coupled to a wall of a fluid chamber. Compressibility is derived from measured pressure changes to the fluid resulting from volumetric changes to the fluid chamber imposed by the mechanical strain of the piezoelectric material resulting from an applied electric field.

Abstract: Methods are provided for tracking carbon dioxide (CO2) migration in a hydrocarbon-bearing reservoir located under a cap rock in a formation. In one embodiment, at least one seismic source and a plurality of receivers are located in spaced boreholes in the formation with the sources and receivers located near or at the reservoir so that direct paths from the sources to the receivers extend through the reservoir. CO2 is injected from the borehole containing the seismic sources into the reservoir, and the sources are activated multiple times over days and seismic signals are detected at the receivers. From the detected signals, time-lapse travel delay of direct arrivals of the signals are found and are used to track CO2 in the reservoir as a function of time. In another embodiment, the sources and receivers are located above the reservoir, and reflected waves are utilized to track the CO2.

Abstract: Methods and apparatus are provided for the measurement of the compressibility of reservoir fluid. A piezoelectric material is coupled to a wall of a fluid chamber. Compressibility is derived from measured pressure changes to the fluid resulting from volumetric changes to the fluid chamber imposed by the mechanical strain of the piezoelectric material resulting from an applied electric field.

Abstract: A formation is characterized by generating a model of the formation that characterizes the formation in a manner consistent with all measurements, thereby permitting a computation or prediction of how the formation will respond to disturbances or stimuli such as fluid injection for production, carbon-dioxide injection for sequestration, current injection, etc. The formation is described with a fundamental set of microscopic parameters such that quantities relevant to petrophysical response at a continuum or macroscopic level can be derived from them. Values for various formation parameters are determined, as are values for various field variables.

Abstract: A method, apparatus, and program product utilize global sensitivity analysis (GSA) based on variance decomposition to calculate and apportion the contributions to a total variance of a measurement signal from uncertain input parameters of a subsurface model in connection with designing targeted surveys. Through the use of global sensitivity analysis in this manner, the geometry for a survey may be determined based on a desired target of the design, e.g., based on spatial properties (e.g., reservoir zone of interest) and/or physical properties (e.g., porosity, fluid density, rock physics properties) to select locations (e.g., source-receiver pairs) with greater uncertainty contributions from parameter group(s) of interest.

Abstract: A CO2 sequestration site is evaluated by incorporating a consistent petrophysical framework having uncertainties expressed in the form of probability density functions of wellbore measurements, by systematically propagating the uncertainties in generating probability density functions or cumulative distribution functions of the parameters used in a reservoir simulation, by using the reservoir simulation to transform the first set of parameters into output variables with uncertainties, and by using the output variables and uncertainties to generate an answer product from which uncertainty levels of performance metrics can be ascertained.

Abstract: Carbon dioxide is sequestered in a formation using dual or multiple completion and injection methods that reduce or eliminates upward leak rates of the sequestered carbon dioxide. The dual or multiple completion and injection method involves the injection of a benign fluid such as brine (water) into a permeable layer of the formation located above the sequestration layer and which is separated form the sequestration layer by a nearly impermeable layer. The water is injected at the same time the carbon dioxide is injected.

Abstract: Methods and apparatus for improving the determination of at least one multiphase flow parameter of an earth formation comprising propagating within the formation a first salinity front, determining a first value of the at least one multiphase flow parameter, propagating in the formation a second salinity front and improving the determination of the at least one multiphase flow parameter from the first value for the at least one multiphase flow parameter and a saturation profile associated with the first and second salinity fronts within the formation.

Abstract: A CO2 sequestration site is evaluated by incorporating a consistent petrophysical framework having uncertainties expressed in the form of probability density functions of wellbore measurements, by systematically propagating the uncertainties in generating probability density functions or cumulative distribution functions of the parameters used in a reservoir simulation, by using the reservoir simulation to transform the first set of parameters into output variables with uncertainties, and by using the output variables and uncertainties to generate an answer product from which uncertainty levels of performance metrics can be ascertained.

Abstract: Carbon dioxide is sequestered in a formation using a dual completion and injection method that reduces or eliminates upward leak rates of the sequestered carbon dioxide. The dual completion and injection method involves the injection of a benign fluid such as brine (water) into a permeable layer of the formation located above the sequestration layer and which is separated form the sequestration layer by a nearly impermeable layer. The water is preferably injected at the same time the carbon dioxide is injected.

Abstract: Carbon dioxide is sequestered in a formation using dual or multiple completion and injection methods that reduce or eliminates upward leak rates of the sequestered carbon dioxide. The dual or multiple completion and injection method involves the injection of a benign fluid such as brine (water) into a permeable layer of the formation located above the sequestration layer and which is separated form the sequestration layer by a nearly impermeable layer. The water is injected at the same time the carbon dioxide is injected.

Abstract: Carbon dioxide is sequestered in a formation using a dual completion and injection method that reduces or eliminates upward leak rates of the sequestered carbon dioxide. The dual completion and injection method involves the injection of a benign fluid such as brine (water) into a permeable layer of the formation located above the sequestration layer and which is separated form the sequestration layer by a nearly impermeable layer. The water is preferably injected at the same time the carbon dioxide is injected.

Abstract: Methods and apparatus for improving the determination of at least one multiphase flow parameter of an earth formation comprising propagating within the formation a first salinity front, determining a first value of the at least one multiphase flow parameter, propagating in the formation a second salinity front and improving the determination of the at least one multiphase flow parameter from the first value for the at least one multiphase flow parameter and a saturation profile associated with the first and second salinity fronts within the formation.