IFSAR AND LIDAR STUDIES TO ESTIMATE THE RATE OF DISPLACEMENT FOR ACTIVE FAULTS IN HOUSTON, TEXAS, USA

Due to many active surface faults, public structures in the greater Houston area have suffered damage, resulting in costly reconstruction and condemnation. This work evaluates LiDAR and IFSAR's utility for mapping faults and to estimate the rate of displacement for these faults in order to predict further damage on existing structures, determine how to mitigate potential hazards, and prevent future construction across the faults. DEM data from 5 year increments over the last 15 years (LiDAR data from 1996 and 2001, and IFSAR data from 2006), specifically over the Eureka Heights fault, have been compared and analyzed with GIS ArcMap software. The original LiDAR data from 1996 is in text file format and was processed using Microsoft Access prior to use with ArcMap where it was formatted into shapefiles in order to perform spatial analysis and to create hillshading, slope and aspect maps. Drawing a polygon along each side of the Eureka Heights fault to use as a mask in surface analyst allowed us to use the statistics of each polygon to derive the average throw. Comparing the LiDAR data of 1996 and 2001 has shown slight changes in the faults. However, the IFSAR data has not displayed the faults clearly due to hindrance from surrounding buildings. This study may additionally result in improving techniques for mapping active faults in urban areas.