Feasibility analysis and Implementation of a Rapid Moment Tensor Algorithm (GRiD MT) for Earthquake Monitoring and Tsunami Warning at French Tsunami Warning Center
Abstract
The French Tsunami Warning Center has the mission to monitor 24/7 large earthquakes, and to warn the population of the danger of potential tsunamis, occurring in the Occidental Mediterranean region and in the North-East Atlantic Ocean. Among the operational goals of the warning center, one is dedicated to the diffusion of an alert message to the French authorities in the 15 minutes following a seismic event, as well as the diffusion of a note to other foreign national warning centers. In order to provide the best information as possible rapidly after an event, the primary features of the seismic sources must be well constrained (i.e., origin time, location, magnitude). Moreover, the focal mechanism of an event of interest is seeked to confirm the risk of a potential triggered tsunami, and to provide inputs for modeling tsunamis heights in different parts of the studied region.
A rapid moment tensor algorithm is under implementation at the French Tsunami Warning Center to respond to the main questions rising after an event: where is the earthquake located? What is its magnitude? Which fault(s) did slip? This algorithm based on the GRiD MT methodology (Kawakatsu 1998 and Guilhem et al., 2011) allows us to provide all the principal information regarding an event of interest within a few minutes after its occurrence. This approach is particularly interesting because it depends on a single processing that respond to all the questions. We present a feasibility study of the GRiD MT approach focusing on the seismicity of the Iberian-Maghreb region, which is a region prone to generate potentially large earthquakes and tsunamis. Prior to its operational implementation, an important work regarding the inversion parametrization (frequency band, station coverage, velocity model, grid dimension) is required. We present the performances of such system for M4.5+ earthquakes and we discuss the required steps and improvements to be made for its full implementation at the French Tsunami Warning Center.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.S53G0555G
- Keywords:
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- 4341 Early warning systems;
- NATURAL HAZARDS;
- 7212 Earthquake ground motions and engineering seismology;
- SEISMOLOGY;
- 7215 Earthquake source observations;
- SEISMOLOGY