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Continuous Resistivity Profiling (CRP): Sample Figures

Sample Inverted CRP Model

Inverted resistivity model from Lake Travis, Austin, Texas.  Cooler colors represent regions of lower resistivity, and warmer colors represent regions of higher resistivity.  The water-bottom begins in the blue-to-green resistivity zones.  Due to the motion of the boat, the effective spacing between electrodes is estimated to be 1 meter.  The inverted resistivity model is shown after 3 iterations, with a root-mean-square error of 3.7 percent.

Sample CRP Field Data and Inverted Models:
Effects of Constraints on Water Column in Inversion Process

Continuous resistivity profiles along the Thames River, Norwich, Connecticut. Effective electrode spacing is 1.0 meter. Cooler colors represent regions of lower resistivity, and warmer colors regions of higher resistivity. a) (top) measured apparent resistivity pseudosection; b) (middle) inverted resistivity model with no constraints on water depth or specific conductance after four iterations with a root-mean-square error of 11.6 percent; and c) inverted resistivity model with constraints on water depth and specific conductance after four iterations with a root-mean-square error of 17.1 percent.