Lidar mapping of faults in Houston, Texas, USA

Over 300 active faults intersect the Earth's surface in the Houston metropolitan area on the northern edge of the Gulf of Mexico basin. These surface faults have caused damage to roads, pipelines, and buildings. We used light detection and ranging (lidar) data to more accurately map faults in the Houston area. We developed a grid-refi nement algorithm for processing the raw data to generate a 1.5-m-resolution digital elevation model (DEM). The refi ned grids allowed for better spatial resolution of the scarps and in some cases revealed features that were not noticed on the original DEM. Hillshading proved the best method for identifying faults that were then examined in the fi eld. Most of these faults are part of a larger, regional, down-to-the-basin fault system along the northern Gulf of Mexico; this work complements studies of Houston and Gulf Coast neotectonics.