This proposal seeks funding to deploy 7 temporary broadbandseismograph stations in a north.south profile at a longitude ofabout 123.oW in western Washington for the purpose of recordingteleseismic body waveforms. We intend to undertake a receiverfunction analysis of the recorded P.waves in order to delineatevariations in the amplitude and timing of Ps conversions from theoceanic Moho of the subducted Juan de Fuca plate that areindicative of variations in the geometry of the subducted slabalong its strike. Specifically, we will attempt to confirm andrefine a working hypothesis recently proposed that suggests thatthe Juan de Fuca plate may be deformed in a broad arch centered inthe vicinity of Puget sound. This model explains certain aspectsof the seismicity beneath this region as well as a number of othergeological and geophysical observations.
