MAPPING QUATERNARY FAULTS IN THE EL PASO-CIUDAD JUAREZ REGION USING DIGITAL GEOLOGY AND GRAVITY

The active Rio Grande Rift is an extensional system that runs through central New Mexico. It is the source of Quaternary deformation in the sedimentary basin between the Franklin Mountains (El Paso, Texas, USA) and the Sierra de Juarez (Juarez, Chihuahua, Mexico). There is suspected Quaternary activity associated with the East Boundary fault of the Franklin Mountains. This fault is cataloged as an active fault in the National Seismic Hazard Map with an estimated slip rate of 0.1 mm/yr. The Eastern Boundary fault is proposed to continue under El Paso–Ciudad Juarez, through urbanized areas, based on well data. Precise gravity modeling will be performed to show the location of the fault through downtown El Paso-Ciudad Juarez. Surveying offset of geomorphic features, mapping of potentially correlative geomorphic surfaces, and GIS analysis of prominent lineaments will be integrated with the gravity data. These datasets will aid in the location of the faults in the El Paso-Ciudad Juarez region, a key task in assessing seismic hazards.