9521929 Nabelek The recent establishment of a braodband seismograph network along the cost of the Pacific northwest and the availability of data from the Navy's offshore hydrophone arrays (SOSUS) provide a framework for long-term monitoring of the seismicity associated with the Juan de Fuca plate and the surrounding ridge-transform system. This project will use the onshore seismograph network to determine magnitudes, depths, source mechanisms, and time histories of earthquakes with magnitudes of 4.0 or greater and will incorporate epicentral locations from the SOSUS arrays determined by NOAA. ***