Instruments and techniques to measure the electrical resistivity of unconsolidated marine sediments have been developed at Texas A&M University. Electrical logging can be performed in situ and upon extruded cores.

The in-situ device using several electrodes makes point resistivity measurements while stationary within the bottom sediments and is thus independent of ship's motion. A minimum number of cores is required to establish the stratigraphy and to calibrate the probe resistivity measurements. The shipboard or laboratory logging system can be used to take continuous readings along a core and also can be used to measure the resistivity of discrete sample units.

The comparison of electrical resistivities of sediments, in particular the formation resistivity factor, with the geotechnical properties of the sediments reveals correlations which indicate that some of these geotechnical properties may be predicted from future resistivity measurements. A series of rapid in-situ measurements then can be made, greatly reducing the number of cores necessary to complete the survey.

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