The Pacific-North America plate boundary evolved from a continent-ocean convergent margin to a transform-dominated rift margin to a transform-dominated rift margin with the passing of the Rivera triple junction in late Miocene time. Baja California, Mexico is one of the areas where the differing roles of extension and strike slip faulting can be documented throughout the evolution of a successful continental rift. This project includes mapping, structural studies, stratigraphic and geochemical studies and Ar/Ar geochronology of Miocene and younger rocks in the southern Sierra Juarez, Baja California. Results will provide insights into the role of continental extension during the transfer of continental crust to an oceanic plate during the transition from a convergent to transform-dominated rift plate boundary.
