Local and Teleseismic Studies of Hawaiian Earthquakes

University Of Hawaii, Honolulu

Investigators

Abstract

Abstract for proposal EAR0106537 (PH #57x) Title: Local and teleseismic studies of Hawaiian earthquakes PI's: Cecily Wolfe, Univ Hawaii Earthquakes in Hawaii are abundant, and provide key information on the nature of magmatic and tectonic processes at this oceanic hotspot. There are shallow crustal earthquakes associated with magma intrusions and eruptions, earthquakes in the middle-to-upper lithospheric mantle suggested to reflect magma migration, earthquakes that relieve stresses due to volcano growth and volcano spreading. In addition, there are enigmatic crustal and mantle earthquakes that may be due to a variety of factors, including inherited zones of structural weakness, stresses due to volcano loading and lithospheric flexure, magma movement, and thermal cooling stresses. This project will conduct two studies: 1) waveform modeling of teleseismically-recorded earthquakes (Mw > 4.5) in order to constrain earthquake mechanisms and moments throughout Hawaii, including in many regions where the United States Geological Observatory Hawaii Volcano Observatory seismic network geometry is insufficient to provide a first-motion mechanism; and 2) the relocation of locally-recorded seismicity for specific targets using high-precision techniques. The combination of teleseismic waveform modeling to yield accurate mechanism solutions and high precision relocations to yield accurate hypocenters promise to improve our view of the seismotectonics of the Hawaiian Islands and will aid in the evaluation of earthquake hazards.