S047-0003
Exploring the Interplate Seismic Rate of the Guerrero Gap from a Novel Amphibious Array
Exploring the Interplate Seismic Rate of the Guerrero Gap from a Novel Amphibious Array
Monday, 14 December 2020
Poster
Abstract:
The Guerrero seismic Gap in Mexico is an enigmatic subduction segment that hosts the largest
slow slip events recorded in the world, but no large megathrust earthquake has occurred in at
least one hundred years. Several mechanisms have been proposed to favor or hindrance the
occurrence of large earthquake. Nonetheless, no nearfield observations had been obtained until
now. We examine the seismic records from a submarine network consisting of seven ocean
bottom seismometers (OBS) that recorded seismic data from 2017-2019 in an effort to detect
unreported seismicity near the trench (Cruz-Atienza et al., 2018). OBS stations were installed
offshore along the western segment of the Guerrero gap, the network is complemented by 15
onshore broadband stations, 33 GPS stations, 7 ocean-bottom pressure gauges and 2 GPS-
Acoustic arrays. With the availability of continuous recordings from OBS, we applied a Match
Filter technique to identify near the trench events that are commonly not recorded by inland
stations. Subsequently, we search for characteristic repeating events that may occurred within
each of the one-year recording periods, a preliminary analysis found 9 candidate repeating
events. Comparison among the spatio-temporal activity of repeating earthquakes , (a)seismic slip
processes in the plate interface and the recent detection of near the trench tremor, allow us to
better elucidate what are the main mechanisms that control the stress release along the Guerrero
gap and what are the implications for the seismic and tsunamic hazard along this segment of the
trench.
slow slip events recorded in the world, but no large megathrust earthquake has occurred in at
least one hundred years. Several mechanisms have been proposed to favor or hindrance the
occurrence of large earthquake. Nonetheless, no nearfield observations had been obtained until
now. We examine the seismic records from a submarine network consisting of seven ocean
bottom seismometers (OBS) that recorded seismic data from 2017-2019 in an effort to detect
unreported seismicity near the trench (Cruz-Atienza et al., 2018). OBS stations were installed
offshore along the western segment of the Guerrero gap, the network is complemented by 15
onshore broadband stations, 33 GPS stations, 7 ocean-bottom pressure gauges and 2 GPS-
Acoustic arrays. With the availability of continuous recordings from OBS, we applied a Match
Filter technique to identify near the trench events that are commonly not recorded by inland
stations. Subsequently, we search for characteristic repeating events that may occurred within
each of the one-year recording periods, a preliminary analysis found 9 candidate repeating
events. Comparison among the spatio-temporal activity of repeating earthquakes , (a)seismic slip
processes in the plate interface and the recent detection of near the trench tremor, allow us to
better elucidate what are the main mechanisms that control the stress release along the Guerrero
gap and what are the implications for the seismic and tsunamic hazard along this segment of the
trench.