This award will enable Prof. R. David Dallmeyer of the University of Georgia to collaborate with Dr. Akira Takasu of Shimane University, Japan, over a period of two years. They will investigate the geochronology of a particular geological formation on the Japanese islands of Shikoku and Honshu, using a radioactive argon isotope dating method to verify and calibrate time-pressure evolutionary histories of the area. The purpose of this research is to enhance our understanding of the thermal and high-pressure phenomena which led to the current status of the geological structure that is known as the Sambagawa terrane in the Japanese islands. Understanding the precise timing, regional distribution, and overprinting relationships of the metamorphic structural events that have contributed to the formation of this terrane would enable geologists to completely assess the thermal effects associated with the various Japanese orogenic cycles, with resulting increase in understanding not only of important Japanese geological events, but of such events anywhere. The U.S. researcher is an expert in the argon dating techniques to be employed, and his Japanese collaborator performed the original survey of the geological history of the Sambagawa terrane.