Cortes Basin offshore landslide interpretation: Implications for engineering projects

Sofia Tovar smiling at the camera wearing a black tshirt

Sofia Tovar Quintero
BS Candidate
Advisor: Dr. Jillian Maloney

Friday, May 4, 2023
10 am in CSL 422
watch Sofia’s talk

Abstract
History has taught us that collaboration between engineering and geology is not always a strong connection. Failure of dams, buildings, bridges, housing developments, and offshore structures serve as a lesson that construction sites need a more detailed geological investigation to achieve a larger threshold of failure. The analysis of offshore landslides can uncover a new perspective of geologic hazards impacting engineering projects and can lead to a better practice of coastal engineering projects. In offshore settings, sediment records are better preserved and not as modified by human development. Additionally, geophysical data allow investigation of larger areas compared to onshore sites. We collected high-resolution subbottom CHIRP data from the Cortes Basin offshore southern California in February 2023. These data were used to investigate faulting and landslides across the basin. Several landslides were identified throughout the data. Here, we show the mapped extent of a landslide interpreted to be ~125 thousand years old. This landslide is well-preserved and demonstrates how high-resolution seismic data can uncover the geometry and distribution of offshore landslides at a scale and resolution that is not often possible in onshore settings. Therefore, study of these offshore landslides can be used to improve assessment of coastal building parameters that may not commonly be included in typical building design.