Exploring possible dynamic triggering of intermediate-depth earthquakes in Northern Chile following the 2010 M8.8 Maule, Chile earthquake

Large earthquakes are capable of triggering small to moderate-size shallow earthquakes, deep tectonic tremor and slow-slip events at long-range distances. A few recent studies have also documented that intermediate-depth earthquakes (IDEQs, i.e., those occurring at the depth range of 70 to 350 km) can also be dynamically triggered by large distant earthquakes (e.g., Price and Wiens, 2019). Such observations can help to better understand potential interactions between shallow megathrust earthquakes and IDEQs, and provide new insights on the physical mechanism of IDEQ, which is not well understood. Here we search for possible evidence of dynamic triggering of IDEQs in Northern Chile following the 2010 M8.8 Maule, Chile earthquake. The study region is well instrumented by the Integrated Plate Boundary Observatory Chile (IPOC) network and other permanent and temporary stations. A recent study has presented a high-resolution relocated catalog of more than 100k earthquakes (Sippl et al., 2018) in Northern Chile, which are separated into plate interfaces, upper plane, lower plane and intermediate-depth clusters. By examining high-frequency waveforms recorded by the IPOC network, Chao et al. (2019) also found possible evidence IDEQs occurring before, during and after the teleseismic waves of the 2010 Maule mainshock. Most of them were not listed in the high-resolution relocated catalog (Sippl et al., 2018). Our next step is to identify and locate these missing earthquakes using template matching or deep-learning techniques, and then examine their temporal behaviors before and after the Chile mainshock searching for significant seismic rate changes. Similar to triggered events at shallow depths, we hope to use dynamic triggering as a probe to reveal the distributions of failure stress at larger depth, and the physical mechanism driving IDEQs.