The principal investigators document the origin of Mesozoic arc development across the Tujunga terrane boundary in southern California. They will utilize field, petrologic, chemical, isotopic, and mineralogic information. An important result will be an evaluation of the magmatic processes operative in the middle and upper crustal portions of continental margin magmatic arcs that overlie or contain a sizeable proportion of Proterozoic basement. In general this information will help geologists under-stand the geologic development of the Earth's crust.
