9505837 WYSS This research is to measure the direction of polarization of the S-waves from local earthquakes recorded by most of the 12 three- component seismograph station in the Alaska network. Emphasis will be placed on those stations where preferred mineral orientation is not likely to be responsible for the anisotropy. The derived stress directions will be compared to those estimated in previously funded NSF work based on inversion of fault-plane solutions. It is important to estimate stress directions from S-polarizations, where this can be done, because there is not enough information available concerning stress directions to understand the seismic hazard in central and southern Alaska. All stress direction estimates (from fault-plane solutions, volcanic dikes, hydrofracture and anisotropy) will be integrated to construct a seismotectonic model for central and southern Alaska. This research is a component of the National Earthquake Hazard Reduction Program. ***
