Using UAV-mounted LiDAR surveys to investigate potential slip rate sites along the northernmost San Jacinto fault zone near its junction with the San Andreas fault in the Cajon Pass area, California

Nate W. Onderdonk, Drake D. Kerr, & Paula M. Figueiredo

Submitted August 9, 2019, SCEC Contribution #9408, 2019 SCEC Annual Meeting Poster #TBD

Paleoseismic data, slip-rate data, and modeling suggest that slip transfer between the San Andreas and San Jacinto faults may occur during simultaneous rupture of the two faults in the Cajon Pass area. To test this idea, slip-rate measurements and paleoseismic data are needed from the major strands of the northernmost San Jacinto fault in the eastern San Gabriel Mountains. Because of the dense vegetation that covers much of the area, LiDAR is a valuable tool for mapping fault traces and identifying offset Quaternary landforms and deposits. We have begun using a LiDAR equipped UAV to investigate and help map potential slip-rate and paleoseismic sites along the northern San Jacinto fault. This UAV system can generate significantly denser LiDAR point clouds than are available from previous aircraft LiDAR surveys and we hope this will enable increased recognition of smaller offset features and better resolution data for measuring offset amounts. We present some results from potential slip-rate sites mapped using the UAV surveys and field investigations, and compare the utility of our UAV LiDAR datasets to two previous LiDAR datasets; the B4 San Andreas fault system dataset and a San Bernardino County dataset.

Key Words
San Jacinto fault, San Andreas fault, Earthquake Gate, Cajon Pass, earthquake geology

Citation
Onderdonk, N. W., Kerr, D. D., & Figueiredo, P. M. (2019, 08). Using UAV-mounted LiDAR surveys to investigate potential slip rate sites along the northernmost San Jacinto fault zone near its junction with the San Andreas fault in the Cajon Pass area, California. Poster Presentation at 2019 SCEC Annual Meeting.


Related Projects & Working Groups
San Andreas Fault System (SAFS)