Initial Reports of the Deep Sea Drilling Project - Volume 71

This volume covers Leg 71 of the cruises of the Drilling Vessel Glomar Challenger. DSDP Leg 71 was the first of five legs designed to study late Mesozoic and Cenozoic paleoenvironments in the South Atlantic Ocean; the broad objectives of Leg 71 were to study the history of sedimentation at the eastern end of the Falkland Plateau, the effect of the plateau as a barrier between water masses during the early opening of the South Atlantic, and the evolution of the Antarctic Convergence. In particular, there were four specific objectives: 1) To expand upon the geologic history of the Falkland Plateau from sediment cores and to assess its influence upon oceanic circulation during the Cenozoic. 2) To study the history of bottom water flow through the region during Cenozoic time on the basis of its erosional, transportational, and depositional consequences, of calcium carbonate dissolution, and of the oxygen isotopic record. 3) To provide Cenozoic biostratigraphic sequences for the South Atlantic. 4) To provide, if coring was successful enough, the Mesozoic sedimentary sequences needed to define the paleoceanographic conditions existing during the early opening and development of the Atlantic Ocean. Five high-priority sites were proposed for Leg 71, but only 4 were drilled (Sites 511-514) between January and February of 1980. Leg 71 began in Valparaiso, Chile and ended in Santos, Brazil.