Tectonic tremor in San Andreas Fault near Cholame captured by a mini seismic array

Kuntal Chaudhuri, & Abhijit Ghosh

Submitted August 15, 2017, SCEC Contribution #7757, 2017 SCEC Annual Meeting Poster #071

The San Andreas Fault, a right lateral strike slip fault, is one of the most well-studied faults on the planet earth. However, our understanding of slow earthquakes, tremor and its relationship with regular earthquakes remains poor. Many studies have reported tremors in the San Andreas Fault near Cholame, our study area, but their spatial and/or temporal resolution are limited. We have installed a mini seismic array in 2013, designed and located specifically to image tremor and other seismic activity near Cholame. It is still operating in continuous mode. Using a Beam Back Projection technique [Ghosh et al., 2009; 2012], we detect about 5 times more duration of tremor activity in this area relative to an envelope cross-correlation method [Nadeau and Dolenc, 2005]. In addition, we locate tremor using this array method assuming that the tremor is located on the San Andreas Fault plane. Their locations are tested and calibrate using cataloged regular micro-earthquakes obtained from ANSS catalog. We are going to present preliminary tremor locations and the its dynamic behavior using this array technique. Higher sensitivity and resolution of our mini array are providing new insights to the underlying physics governing slow earthquakes, its broad spectrum and its potential connection to the regular earthquakes.

Citation
Chaudhuri, K., & Ghosh, A. (2017, 08). Tectonic tremor in San Andreas Fault near Cholame captured by a mini seismic array. Poster Presentation at 2017 SCEC Annual Meeting.


Related Projects & Working Groups
Seismology