Abstract: A method of seismic modeling using an elastic model, the elastic model including a grid having a grid spacing sized such that, when synthetic seismic data is generated using the elastic model, synthetic shear wave data exhibits numerical dispersion, the method including: generating generated synthetic seismic data using the elastic model, wherein the generated synthetic seismic data includes synthetic compression wave data and synthetic shear wave data, and modifying the generated synthetic seismic data to produce modified synthetic seismic data by attenuating at least some of the synthetic shear wave data in order to attenuate at least some of the numerically dispersive data.

Abstract: A method of solving a geophysical inverse problem for estimating a physical parameter, the method comprising providing a model vector representing the physical parameter, transforming the model vector by a first operator to provide a first transformed model vector, solve the inverse problem for the first transformed model vector to provide a first solution, transforming the model vector by a second operator to produce a second transformed model vector, solve the inverse problem for the second transformed model vector to provide a second solution, calculating a weighted sum of the first solution and the second solution.

Abstract: A method of seismic modeling using an elastic model, the elastic model including a grid having a grid spacing sized such that, when synthetic seismic data is generated using the elastic model, synthetic shear wave data exhibits numerical dispersion, the method including: generating generated synthetic seismic data using the elastic model, wherein the generated synthetic seismic data includes synthetic compression wave data and synthetic shear wave data, and modifying the generated synthetic seismic data to produce modified synthetic seismic data by attenuating at least some of the synthetic shear wave data in order to attenuate at least some of the numerically dispersive data.

Abstract: A method of solving a geophysical inverse problem for estimating a physical parameter, the method comprising providing a model vector representing the physical parameter, transforming the model vector by a first operator to provide a first transformed model vector, solve the inverse problem for the first transformed model vector to provide a first solution, transforming the model vector by a second operator to produce a second transformed model vector, solve the inverse problem for the second transformed model vector to provide a second solution, calculating a weighted sum of the first solution and the second solution.

Abstract: A method for measuring an enhanced electromagnetic field response, especially in a submarine environment, for the purposes of subsurface data acquisition and processing. An electromagnetic field is applied to subterranean strata at two or more different frequencies, a response at each frequency is detected, and the responses at different frequencies are resolved. The differences in the phase and/or amplitude of the responses are analyzed and the nature of the strata is determined. The same method can be used to determine the hydrocarbon content of a reservoir via the use of a borehole.

Abstract: A method for measuring an enhanced electromagnetic field response, especially in a submarine environment, for the purposes of subsurface data acquisition and processing. An electromagnetic field is applied to subterranean strata at two or more different frequencies, a response at each frequency is detected, and the responses at different frequencies are resolved. The differences in the phase and/or amplitude of the responses are analyzed and the nature of the strata is determined. The same method can be used to determine the hydrocarbon content of a reservoir via the use of a borehole.