IAG-IASPEI 2017

Presentation information

Poster

IASPEI Symposia » S03. Imaging of heterogeneities in the Earth with seismic scattered waves and ambient noise

[S03-P] Poster

Wed. Aug 2, 2017 3:30 PM - 4:30 PM Shinsho Hall (The KOBE Chamber of Commerce and Industry, 3F)

3:30 PM - 4:30 PM

[S03-P-11] Study of repeating events in the Jalisco subduction zone, Mexico

Guillermo Gonzalez1, Allen Husker1, William Frank2, Leticia Avila1 (1.Universidad Nacional Autonoma de Mexico, 2.Massachusetts Institute of Technology)

Low Frequency earthquakes (LFEs) as well as repeating low amplitude regular earthquakes are both observed in the Jalisco subduction zone, Mexico. We use the “Mapping the Rivera Subduction Zone" (MARS) seismic array, which is a large array of 51 stations located in Jalisco, Colima and part of Michoacan, to detect and locate them. This is done in both cases with a matched filter search (Frank et al., 2014). The templates for the repeating earthquakes are found by stepping through 10s windows and cross-correlating those with the rest of the data stream on a single station. High correlation coefficients that match in time with other stations are found to be events/templates. These templates are then used in the matched filter over the array spanning at least eight months. The LFEs are much smaller than the regular earthquakes. In order to find them, specific move-outs are used by grid searching in zones where tectonic tremor (TT) has previously been found. Nonetheless, the detection of LFE's has been difficult and do not match TT activity in the zone so far. The main reason for this is that few LFE templates above the TT background signal have been observed.