Cenozoic Deep Water History on Ceara Rise: An Integrated Geophysical and Sedimentological Survey

点击翻译按钮获取中文摘要

During the last few years, the Ocean Drilling Program has employed a sampling strategy in which bathymetric transects are drilled on aseismic ridges in order to reconstruct the Cenozoic history of carbonate production and dissolution, and deep water chemistry and circulation. This strategy has evolved from similar shallow coring programs examining late Quaternary oceanographic history. Carbonate accumulation in the shallowest sites of the depth transect approximates carbonate productivity in the overlying waters. If the sites are close together and only vary in depth, the accumulation rates will record carbonate dissolution which will be controlled by changes in bottom water chemistry. The objective of the present project is to acquire seismic data and core samples from the Ceara Rise in the western equatorial Atlantic. The Ceara Rise is capped by a thick section of Cenozoic sediments and should be an ideal site for a depth transect study. Additionally, the data to be acquired will form the basis for a detailed ODP drilling program which has been proposed for this area.