The Amazon Deep-Sea Fan is a typical large modern deep-sea fan. Past studies have shown the structure and surface morphology of the fan, including the location and character of the most recently active channel. Cores collected in the vicinity of this channel sample the sediments deposited by channelized flows before activity cease following post-glacial sea level rise. We need to determine dates on, and to correlate between, cores on the fan to relate sediment sequence to sea level and to each other. We propose here (1) to develop a stratigraphy which will allow us to determine the age of sedimentary activity of the fan, (2) to use morphological and sedimentological data to determine the likely characteristics of latest Pleistocene channelized turbidity currents and (3) to integrate the age and sediment facies data with the morphologic and seismic data available on the fan. The stratigraphy will be based on delta 0-18 curves supplemented with C-14 dates. Delta 0-18 can be measured on samples containing few foraminifera, an advantage in cores with high sedimentation rates. C-14 dates on planktonic foraminifera and occasional wood fragments (using AMS techniques) and pollen analysis will constrain the chronostratigraphy. Benchmark stratigraphies, developed in areas where downslope flows are minimal, will be carefully brought to areas where downslope flows are more common, and zones of downslope transport will be identified based on structure and grain size characteristics. The high- resolution 0-18 stratigraphy will also help us to assess the role of the Amazon River, the North Brazil Coastal Current and the Equatorial Countercurrent in determining late glacial/early interglacial paleoclimate.
