Use of LiDAR Data for Neotectonic Evaluation of Superstition Hills and Superstition Mountain, Salton Trough, California

Abstract

Analysis and interpretation of LiDAR data acquired at Naval Air Facility El Centro in the western Salton Trough, California, provides new information on the location and style of active deformation at Superstition Mountain and in the Superstition Hills that is potentially relevant for geothermal exploration. Faulting along the northeastern piedmont of Superstition Mountain occurs within a strike-slip duplex, wherein dextral slip is systematically transferred in left-restraining steps among fault strands. The valley floor between Superstition Mountain and Superstition Hills is gently folded and warped about broad, east-trending axes. These observations are consistent with stress inversions of earthquake focal mechanisms in this region, which indicate transpressional tectonics between the Superstition Mountain and Superstition Hills faults. In contrast, a crustal block in the Superstition Hills that is bounded on the west by the sinistral Elmore Ranch fault and on the south by the dextral Superstition Hills fault is accommodating internal extension. The intersection of these two faults is an example of a dilational fault intersection per Faulds et al. (2011); Navy property within this extending block may be a preferred target for further exploration. Other localized areas of extension, some associated with youthful carbonate cementation, occur in releasing stepovers among sinistral fault strands in the Superstition Hills and also may be targets for additional study.