Rapid GPS-based determination of earthquake displacement field and magnitude for tsunami propagation modeling and warning

摘要

Reliable tsunami early warning requires a rapid assessment of the tsunamigenic potential of an earthquake as well as a prediction of the likely propagation pattern of the tsunami. Low-latency availability of the coseismic Earth's surface displacements can support the assessment of the tsunamigenic potential of an earthquake and improve predictions of the propagation pattern of the tsunami. We have developed a fingerprint methodology for the rapid determination of the surface displacement field from GNSS-determined displacements. The fingerprint methodology depends on a priori knowledge of the faults potentially involved in a rupture. The known faults are parametrized with standard elements and for each element so-called fingerprint functions are computed for unit strike and dip slips. After an event, the model space of all reasonable fault-element combinations is searched for the element-slip combination best fitting the observed displacements. This combination provides the best estimate of the displacement field and earthquake magnitude consistent with observations. Here we describe the fingerprint methodology and the main architectural elements of a prototype for the rapid determination of magnitude and displacement field.