The Seismo-Lineament Analysis Method (SLAM) applied to the South Napa Earthquake and antecedent events.
Earthquake data from the M 6.0 South Napa Earthquake of 24 August 2014 and other local seismic events were utilized in the Seismo-Lineament Analysis Method (SLAM) to locate seismogenic faults in the Napa Valley. Focal mechanism solutions and corresponding uncertainties were used to generate seismo-lineaments. Geomorphic analysis and field work located surficial fault-related damage, which was analyzed for trends with previously mapped surface ruptures. GPS strain was calculated in the area to determine regional stress before, during, and after the South Napa earthquake. The seismo-lineament produced for the South Napa earthquake included the areas of known surface rupture after the M 6.0 event. Results also suggest that data from previous earthquakes, especially the M 4.9 Yountville earthquake of 2000, could have been used to identify the western portion of the West Napa fault zone as seismogenic before the South Napa earthquake.