Detection of active faults using geophysics, Houston, Texas

It was once, during the early 2000s, believed by geologists and engineers that  geophysical methods were not capable of detecting active faults in the Gulf Coast area. To test whether this was true or not, we (myself and Bob Van Nieuwenhuise) performed resistivity, conductivity (EM31), micro-gravity and magnetic surveys over the Willow Creek Fault, which is located in the NW part of Houston.   All methods provided pertinent information on the fault and we published the results in year 2006 in The Leading Edge. Since then we conducted number of studies over different faults  with the same satisfactory results and published them as well.

Note that the high gravity values are observed on the down-thrown side, not on the up-thrown side. This is a phenomena that we witnessed over other major active growth faults.