This award supports an ongoing U.S.-Japan collaborative research project between John Beavan and Chris Scholz of Lamont-Doherty Geological Observatory, Columbia University, and Teruyuki Kato, Earthquake Research Institute, University of Tokyo. This project is part of a five-year collaboration to resolve several major problems related to the active tectonics of the Philippine Sea Plate and its boundaries through collection and analysis of Global Positioning System (GPS) measurements at sites strategically placed along the eastern, western, and northern boundaries of the Philippine Sea Plate in southeast Japan, the Ryukyus, Taiwan, and in the Bonins, Marianas, and Micronesia. During the two-year period of the grant, the following specific topics will be addressed: (1) determination of accurate Philippine - Eurasian Plate and Philippine Sea-Pacific poles and rotation rates; (2) the magnitude of plate driving forces at trench boundaries; (3) the mechanism of back-arc spreading; (4) the mechanism of strike-slip in the forearc; (5) the mechanics of arc-continent collision; and (6) the distribution of deformation and seismic hazard in southeast Japan and Taiwan. In addition to the principal investigators, others involved in the project are Dan Davis, SUNY Stony Brook; Steven Roecker, Rensselaer Polytechnic Institute; Kazuro Hirahara and T. Tanaka, Kyoto University; and I Murata, T. Kato, and S. Nakao, University of Tokyo. This grant complements a grant from the NSF Earth Sciences Program, which is funding the research in the United States.
