9404962 Ward This research is to analyze the regularity of recurrence of large earthquakes (M greater than 7) from major plate boundaries around the world. Regularity of earthquake recurrence is a critical input into many seismic hazard studies. Many of the previous studies of earthquake recurrence have concentrated on "characteristic", segment-breaking events. However, both the definition of segments and the selection of "characteristic" events are not unambiguous. By analyzing a large number of recurrence series and establishing a set of objective selection criteria, the study will quantify systematically the regularity of large earthquakes. This research is a component of the National Earthquake Hazard Reduction Program. ***
