UC San Diego

This dissertation presents an optimal combination algorithm for strong motion seismograms and regional high rate GPS recordings. This seismogeodetic solution produces estimates of ground motion that recover the whole seismic spectrum, from the permanent deformation to the Nyquist frequency of the accelerometer. This algorithm will be demonstrated and evaluated through outdoor shake table tests and recordings of large earthquakes, notably the 2010 Mw 7.2 El Mayor-Cucapah earthquake and the 2011 Mw 9.0 Tohoku-oki events. This dissertations will also show that strong motion velocity and displacement data obtained from the seismogeodetic solution can be instrumental to quickly determine basic parameters of the earthquake source. We will show how GPS and seismogeodetic data can produce rapid estimates of centroid moment tensors, static slip inversions, and most importantly, kinematic slip inversions. Throughout the dissertation special emphasis will be placed on how to compute these source models with minimal interaction from a network operator. Finally we will show that the incorporation of off-shore data such as ocean-bottom pressure and RTK-GPS buoys can better- constrain the shallow slip of large subduction events. We will demonstrate through numerical simulations of tsunami propagation that the earthquake sources derived from the seismogeodetic and ocean-based sensors is detailed enough to provide a timely and accurate assessment of expected tsunami intensity immediately following a large earthquake