High resistivity indicates hydrocarbon presence
Hydrocarbon saturated sediments display higher resistivity than water-filled sediments. This observation has been used since the 1920's by the borehole logging community to confirm oil in place.
What EMGS has achieved, where many others have previously failed, is to apply this principle to the remote indication of hydrocarbons - that is, to measure subsurface resistivity from the seabed.
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