Subsurface Fault and Colluvial Wedge Detection Using Resistivity, Refraction Tomography and Seismic Reflection

Electric resistivity tomography (ERT), seismic refraction tomography, and seismic reflection are widely used in shallow geological applications such as fault detection. In this work we use the three methods to find and trace a shallow subsurface fault. A low velocity-low resistivity anomaly is shown on the velocity tomogram and the ERT, respectively. This anomaly is interpreted as a colluvial wedge located at the downthrown side of the fault. Comparing the results from the three methods show a very good match in the fault location, colluvial wedge location, thickness and width, as well as the different subsurface geological units.