METHOD FOR ENHANCED SUBSURFACE ELECTROMAGNETIC SENSITIVITY

摘要

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 analysed 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.