The tectonic evolution of West Antarctica and its relationship to East Antarctica is the most fundamental tectonic problem of the Antarctic continent. It bears on global plate interaction, paleocirculation in the Southern Ocean, paleoenvironment, and paleobiogeography as well as being critical to the development of the continent itself. The joint United States-United Kingdom West Antarctic Tectonics Project (1983-88) has shed considerable light in the tectonic evolution of the Weddell Sea region. This award supports a new tripartite United States-New Zealand- United Kingdom program of the study in Marie Byrd Land for the years 1990-93 to complete our understanding of the tectonic evolution of the southern rim of the Pacific Ocean basin. It will involve field and laboratory investigations designed to elucidate the structure and evolution of Marie Byrd Land crustal block and its relationship to other West Antarctic crustal block, the East Antarctic craton, New Zealand and the Pacific Ocean basin. This study is the major U.S. contribution to the program and involves structural, paleomagnetic, petrologic, and geochronologic investigations bearing particularly on the pre-Cenozoic development of Marie Byrd Land.
