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 fundamental to the development of the continent itself. The joint United States-United Kingdom West Antarctic Tectonics Project (1983-88) has shed considerable light on the tectonic evolution of the Weddell Sea region. A tripartite United States -New Zealand-United Kingdom program of study in Marie Byrd Land is planned 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 the 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 involves structural, paleomagnetic and geochronologic investigations bearing particularly on the pre-Cenozoic development and Marie Byrd Land.
