Defining the architecture and recurrence interval for faults in the Sacramento-San Joaquin Delta: Assessing potential geohazards

R/SF-81
Start/End: March, 2017 to February, 2019

The faults that run through the Delta are poorly understood and are designated as “blind faults,” which makes them difficult to study on land. Potential active faults pose a risk to the levee systems that—if they were to collapse—could inundate agricultural land and contaminate the freshwater source. Continuous and detailed maps are critical for developing seismic risk assessments, better preparing for future disasters, and protecting built infrastructure and the environment.

This project will characterize faults in the Sacramento-San Joaquin Delta. Specifically, researchers will:

  1. Generate detailed fault maps to analyze the geometry and continuity of the fault zones by performing a seismic reflection survey.
  2. Radiocarbon date materials collected from two different types of sediment cores to determine estimates for most recent earthquake events.

This research will be used by the California Department of Water Resources and U.S. Geological Survey to advance the understanding of seismic activity within the Delta and develop an overall geologic framework that can be used in models and risk assessments.