Real Time GNSS Network Operating Along Strongly Coupled Segment of Ecuador Subduction Interface

Session: Advances in Real-Time GNSS Data Analysis and Network Operations for Hazards Monitoring
Type: Oral
Date: 4/30/2020
Time: 02:00 PM
Room: 230 + 235
Description: 

The Esmeraldas-Nariño segment of the Ecuador-Colombia subduction zone is strongly coupled, as demonstrated by 10 years of CGPS measurements, and patches of this segment are perhaps primed for rupture. Large megathrust seismic events occurred recently in 2016 with an Mw=7.8 located on the segment´s southern end and to the north in 1958=Mw 7.7 and 1979=Mw 8.2. The entire segment ruptured in 1906=Mw 8.4, over a 500 km length.

In anticipation of registering real-time GNSS displacements of future large earthquakes at the subduction interface, the Instituto Geofísico of the Escuela Politécnica Nacional, Quito (IGEPN) is operating a 7 station real time GNSS network along a 200 km stretch of the coastal margin, from the Colombian border south to the town of Mompiche. Each station has a 40 km distance between them and all are located on the littoral, some 70 km inland from the trench. Data is sent via satellite, microwave or public IP to the IGEPN where an NTRIP castor is employed to send data streams to other stakeholders.

We aspire to employ peak ground displacements (PDG) and coseismic offsets from the RT data streams for determining earthquake magnitude within a few 10s of seconds. RT GNSS determinations will be incorporated into our seismic monitoring operations. Magnitude determination will also be applied to tsunami early warning systems. We believe that the Esmeraldas real time GNSS network is probably ideally located to record the next large subduction earthquake in NW South America, just as the Ridgecrest, California M= 7.1 earthquake was well registered by NOTA (Network of the Americas) permanent real time GNSS stations. This work is a collaboration between the IGEPN, ECU-911, World Bank, Central Washington University, UNAVCO, Inc. and the University of Chile.

Presenting Author: Patricia A. Mothes

Authors