From Bombay Beach to Carrizo Plain: Highlights from the first CERI San Andreas Field Trip, July 25-29, 2022

Christodoulos Kyriakopoulos, Thomas H. Goebel, Roshan R. Bhattarai, Kiran Pandey, Roshan Koirala, & Luis I. Bazán Flores

Published September 11, 2022, SCEC Contribution #12269, 2022 SCEC Annual Meeting Poster #276 (PDF)

Here we are presenting a photographic diary of a five-day long (July 25-29, 2022) field trip along the Southern San Andreas Fault (SSAF) organized by the Center for Earthquake Research and Information (CERI) at the University of Memphis. We started our field trip with a stop at Bombay Beach, the commonly accepted southern end of the SAF. Next, the group had the opportunity to explore and make observations inside a geologic trench (Salt Creek) intersecting the SSAF. After the exploration of the eastern shore we moved to the geothermal area (southeast end of Salton Sea), visiting the Red Hill rhyolitic dome and observed an array of mud volcanoes at the intersection of Davis and Schrimpf roads. The final part of the day was dedicated to the exploration of the spectacular stratigraphy of the Mecca hills inside Box Canyon. In the second day we shifted our attention to the northern portion of the Coachella Valley and the complexities of the San Gorgonio Pass (SGP). At the end of the day the group “climbed” to the top of Mt San Jacinto using the Palm Springs aerial tramway. From here, the panoramic view of the Coachella Valley and SGP offered a new prospective on the topics discussed during the first part of the day. In the first part of the third day the group visited the Elsinore fault zone and its local geomorphic expressions. More specifically the students had the opportunity to make observations on both compressional and extensional features generated by the combination of strike slip motion and step-over regions. During the second part of the day the group returned to the SAF and followed the geomorphic expression of the fault across the Cajon Pass. The fourth day the group moved to the SSAF Mojave segment. We started along the Big Pine Hwy to locate and experience firsthand how plutonic and metamorphic rocks have been mechanically pulverized by highly energetic SSAF events. Subsequently, we hiked around the area of the Punchbowl fault geologic site. We closed our day with the exploration of the Pallet Creek paleo-seismological site. The fifth and last day of the field trip the group explored the SSAF along the Carrizo plain. We started our day at Wallace Creek, observing the impressive shift between the upstream and downstream part of a 3800-year-old channel. During the second part of the day, we moved southeast and climbed the ridges of the probably most iconic SAF geomorphic expression along the Elkhorn scarp pressure ridge.

Key Words
Field trip, San Andreas, CERI

Citation
Kyriakopoulos, C., Goebel, T. H., Bhattarai, R. R., Pandey, K., Koirala, R., & Bazán Flores, L. I. (2022, 09). From Bombay Beach to Carrizo Plain: Highlights from the first CERI San Andreas Field Trip, July 25-29, 2022. Poster Presentation at 2022 SCEC Annual Meeting.

Related Projects & Working Groups
Communication, Education, and Outreach (CEO)