Analysis of the Mw 6.7 Coquimbo-La Serena Earthquake of June 14th, 2019: Preliminary Results Determined with a High Density Local Seismic Network

By the end of December 2018, 88 short period (4.5 Hz) there components, continuous recording seismic stations were deployed in northern Chile through a joint KIT-AMTC (U. de Chile) project. The seismic network spanned between Chañaral (26.3°S) and Ovalle (30.8°S), covering from coast to the Chilean-Argentinian political boundary. On January 20^th, 2019 the area located at the southern edge of this network (close to Coquimbo-La Serena) experienced an Mw6.7 normal fault intraplate earthquake. This earthquake triggered a high level of seismicity around that area, including an Mw6.4 off-shore interplate earthquake on June 14^th, 2019 and tens earthquakes with magnitude larger than 5. All of this seismic activity was recorded by the temporary seismic network, and the aim of this work is to present the preliminary results associated to this sequence, that coincides with the northern edge of the Mw8.4 2015 Illapel earthquake, and the southern edge of the rupture zone of the Mw8.5 1922 Copiapo earthquake. The dataset recorded between December 2018 and July 2019, will be used to determine a 3D body wave velocity model through a seismic tomography, what will allow us to define the main Vp, Vs, and Vp/Vs anomalies, and a robust hypocentral determination of the whole sequence.