Slow slip and potential earthquake triggering near Guerrero, Mexico from geodetic remote sensing

Slow slip events (SSEs) are known to occur episodically along subduction zones, in areas known as "seismic gaps" that seldom produce large earthquakes. The Guerrero seismic gap in Mexico has seen several SSEs, the most recent having been observed in 2017. These events can change the local stress field and could be responsible for triggering large earthquakes, and they provide an opportunity for studying mechanical conditions on subduction zone faults near areas of fast earthquake nucleation. The Sentinel-1 Interferometric Synthetic Aperture Radar (InSAR) mission provides geodetic deformation measurements with unprecedented coverage, having data acquisitions every 6-12 days and high spatial resolution, which allow for constraining the spatio-temporal evolution of slow events. We use data from the Sentinel-1 mission and regional Global Navigation Satellite System (GNSS) stations to constrain the full 3-dimensional deformation due to the 2017 Guerrero SSE, by combining GNSS time series with InSAR time series from two different look geometries. We estimate cumulative slip and investigate the spatial temporal aspects of how deformation and slip evolve during the event. Finally, we investigate the impact of the SSE on the local stress field and discuss possible triggering relationships between SSEs and large earthquakes on this part of the Mexico subduction zone.