Abstract: A method of hydraulic fracturing geometry evaluation, comprising injecting a fracturing fluid comprising a magnetic material into a fracture, measuring a field affected by the fracturing fluid in the fracture, and modeling, based on the measuring, a geometry of the fracture.

Abstract: A method for estimating a displacement of a fluid-to-hydrocarbon interface in a reservoir in the earth includes: disposing an electrode in an injector borehole that is configured to inject a fluid into the reservoir; energizing the electrode with a voltage source to apply a voltage to the reservoir; disposing an electric field sensor in the injector borehole; disposing a gravity sensor in at least one of the injector borehole and a producer borehole that is offset a distance L from the injector borehole; injecting fluid into the reservoir; measuring a magnitude of a time-varying electric field due to the injecting using the electric field sensor to provide electric field measurements; measuring a magnitude of a time-varying gravitational field due to the injecting using the gravity sensor to provide gravitational field measurements; and estimating the displacement using the electric field measurements and the gravitational field measurements.

Abstract: A method of hydraulic fracturing geometry evaluation, comprising injecting a fracturing fluid comprising a magnetic material into a fracture, measuring a field affected by the fracturing fluid in the fracture, and modeling, based on the measuring, a geometry of the fracture.

Abstract: A method for estimating a displacement of a fluid-to-hydrocarbon interface in a reservoir in the earth includes: disposing an electrode in an injector borehole that is configured to inject a fluid into the reservoir; energizing the electrode with a voltage source to apply a voltage to the reservoir; disposing an electric field sensor in the injector borehole; disposing a gravity sensor in at least one of the injector borehole and a producer borehole that is offset a distance L from the injector borehole; injecting fluid into the reservoir; measuring a magnitude of a time-varying electric field due to the injecting using the electric field sensor to provide electric field measurements; measuring a magnitude of a time-varying gravitational field due to the injecting using the gravity sensor to provide gravitational field measurements; and estimating the displacement using the electric field measurements and the gravitational field measurements.

Abstract: An apparatus and method for estimating at least one parameter of interest for an earth formation by reducing an uncertainty in seismic parameters using density information. The density information may be acquired from borehole gravity information. The method may include inverting seismic parameters while using density information obtained from borehole gravity information. The method may also include joint inversion of seismic parameters with density information. The apparatus may include a gravimeter and a processor configured to estimate the parameter of interest using the seismic parameters and density information.