The objective of the study is to explore the long-term burial fluxes of North African dust and equatorial Atlantic biogenic opal at two Leg 108 ODP sites. Four causal factors will be focused on: insolation forcing, northern Hemisphere ice sheets, tectonic uplift and linkages between equatorial and Antarctic circulation. Stable isotopic stratigraphy will provide time resolution and define the fluxes of opal and dust at orbital band (20 to 100 K.yrs.) and facilitate comparison with other climatic proxies. Clay mineral analysis will provide record of African aridity. Uplift influence will be assessed through modeling using the General Circulation Model. The study is a continuation of the PI's extremely productive line of investigation. It extends his previous work further back in time as well as broadens the scope.