Sedimentation in the Modern Delta of the River Niger, West Africa

Abstract

The chapter is based on observations made at more than 1,000 sample stations during a survey jointly organized and financed by Shell Internationale Research Maatschappij N.V. and The British Petroleum Company Limited. The cycle of deposits present in the modern Niger delta has been built up during a transgression of the sea (Late Glacial to earlier Holocene) and a subsequent regression (later Holocene). Quartz sands enriched with glauconite or shell debris were deposited at an advancing strand line during the transgression. The regression of the sea has been accompanied by the distribution, by wave and current action, of terrigenous sand, silt, clay, and plant debris among the following principal environments: floodplain, mangrove swamp, estuary, beach with beach-ridges, river mouth bar, delta platform, prodelta slope, open shelf, and continental slope. The lithofacies deposited in these environments overlie the earlier transgressive sands.