Investigation of Remotely Triggered Tremor and Earthquakes in Latin America

Abstract:

It has been shown that non-volcanic tremor (NVT) as well as small to moderate size earthquakes can be triggered by the seismic waves from distant earthquakes; however, little is understood about the triggering mechanisms. Investigating cases of remote triggering offers the opportunity to improve our knowledge about the physical mechanisms of earthquake interaction and nucleation. Furthermore, the similarities observed between remotely triggered NVT and those related to slow slip events, suggest that investigating triggered NVT may give us important insights into the mechanisms involved in slow slip events and their potential role in the earthquake cycle. In this work we present new results and the techniques we employ in identifying, locating and modeling cases of triggered earthquakes and NVT in Latin America and the Caribbean. In particular, we use global and regional seismic networks to perform an intensive search for triggered seismicity in Mexico, Cuba, Nicaragua, Costa Rica, Colombia, Ecuador, Peru, Bolivia, and Chile. Our results suggest that seismicity can be triggered in a broad variety of tectonic environments, depending strongly on the triggering dynamic stress amplitude and orientation. This investigation will help to define the regions where remote triggering occurs and their susceptibility to undergo an important increase in seismicity after the occurrence of a distant large earthquake.