A GEOPHYSICAL DELINEATION OF A LISTRIC FAULT WITHIN THE GULF COASTAL PLAIN, MONTGOMERY COUNTY, TEXAS

The Gulf Coast of Texas has been a known hydrocarbon basin for many years because of its various structural trapping mechanisms such as faults and salt domes. While salt domes have been extensively studied in the Gulf Coastal Plain, many faults have been mapped but not significantly studied. This research study employs an integrated geophysical approach to mapping the Big Barn fault located in Montgomery County, Texas. This fault is found on the Gulf Coastal Plain and is approximately 20 miles north of Houston, Texas. Significant normal faults found in the Gulf Coastal Plain generally formed during the Jurassic opening of the Gulf of Mexico basin. The Gulf of Mexico formed due to the breakup of Pangea and the rifting of North and South America. The Big Barn fault formed during the Jurassic but there is evidence that the fault plane has been recently reactivated. Within the past 20 years extensive deformation and fractures have formed on Interstate 45 and have caused damages to nearby businesses and residences. Gravity and electrical resistivity studies were completed to investigate the cause of deformation. The area was also geologically mapped to determine the extent of faulting. Two-dimensional inverted resistivity models were made to determine the structures and stratigraphy of the area.