Development of a passive transform margin: Côte d’Ivoire–Ghana transform margin – ODP Leg 159 preliminary results

Abstract

 The Côte d’Ivoire–Ghana transform margin is bounded to the south by a prominent marginal ridge. ODP Leg 159 shipboard analyses on sediments from four sites document three distinct transform margin sedimentary and tectonic stages of evolution: (1) an intracontinental stage of transform faulting recorded in deformed lacustrine to marine siliciclastic sequences; (2) a marginal ridge uplift stage, recorded by shallow water limestones, appears coeval with the passing of a hot, oceanic spreading center just south of the sediment wedge; and (3) cool ing subsidence of the transform margin recorded in bathyal to abyssal sediments emphasizes a passive margin stage. These results are consistent with previously published models of evolution.