3D Resistivity Tomography Sinkhole Mapping

Three dimensional resistivity services can map complex terrain to accurately represent subsurface features needed for engineering design. Sinkhole mapping of karst terrain is a perfect example of an application that greatly benefits from 3D resistivity tomography. The three dimensional resistivity survey covered approximately 35 acres with over 1800 electrodes. The results are presented as a slice through the model at a depth of 65 feet. The resistive sinkhole features are shown to have large diameters, in some cases extending over 375 feet across. Borehole data and standard penetrometer testing (locations of each test are presented as squares within the contoured model) validated the three dimensional resistivity survey by confirming the presence (and absence) of competent rock and areas prone to raveling on the edge of sinkholes.