INVESTIGATING RECENTLY ACTIVE FAULTS USING GEOMORPHIC ANALYSES OF EPHEMERAL CHANNELS IN THE GUADALUPE MOUNTAINS, WEST TEXAS AND NEW MEXICO

Earthquakes can strike at any given time without warning; understanding fault activity is important when it comes to potential geohazards. The Guadalupe Mountains, located in western Texas and southeastern New Mexico, consist of several normal faults that run throughout the entire range. Our goal is to find how active these faults are by analyzing the geomorphology of stream channels that intersect these faults lines. This methodology can be useful to detect activity without having to use expensive seismic equipment when studying large-scale terrains such as the Guadalupe Mountains. The geomorphologic analysis of the landscape also sheds light on the recent extensional processes, additional uplift, and mantle upwelling that might be occurring in the area. Using Google Earth and ArcGIS, we focused on 5 groups of faults positioned from east to west in the Guadalupe Mountain Range. We classified and graphed the stream segments in those groups that had crossed faults using the Shreve stream order classification method. We then uploaded the data into ArcGIS and quantified the lengths using Excel. We identified areas that were the most recently active through correlation between fault locations and stream features in the range. We also performed a physical experiment to better understand the interactions between active and inactive faults. The results of our research suggest that the stream patterns are directly influenced by the faults that lie underneath them and can impact erosional and sedimentation processes in the Guadalupe Mountains. Furthermore, the seismic activity from active faults and extensional stresses can fracture nearby rock units that are near other inactive faults. Overall, this will affect the geomorphology and behavior of the stream channels in the surrounding areas. In conclusion, stream channel geomorphology can tell us much about the ongoing processes and make us aware of the most tectonically active areas within the Guadalupe Mountain Range.