The continental terminal in West Africa

Land clearance and hydrological change in the Sahel: SW Niger

“…The Continental Terminal outcrops over a surface area of 150 000 km 2 in Niger and extends further in West Africa (Lang et al, 1990). The landscape reflects the succession of former wetter and drier climatic conditions.…”

Contribution of magnetic resonance sounding to aquifer characterization and recharge estimate in semiarid Niger

“…The study area is located in the south-western Niger, between the Niger River and the large dry valley of the Dallol Bosso Tertiary sedimentary rocks which outcrop over a large surface area consist of loosely cemented clays, silts and sands of continental origin (Lang et al, 1990). These are locally overlaid by Quaternary aeolian sand deposits up to few metres thick.…”

Paleogeographic and structural evolution of northwestern Africa and its Atlantic margins since the early Mesozoic

“…The preservation of bauxites over the Nigerian shield and the Bida rift (Valeton, 1991) precludes the connection between the equatorial Atlantic Ocean and the Tethys (Chardon et al, 2016). Because continental chemical weathering is favored, correlative carbonates and phosphates are found in all West African basins, and clastic fluxes through the river systems are subdued (e.g., Lang et al, 1990;Valeton, 1991;Johnson et al, 2000). The size of the erosional domain did not evolve significantly and a continuous marginal upwarp was re-installed.…”

“…Marine sedimentation is recorded repeatedly until the Late Paleo ceneEarly Eocene, particularly in the Iullemmeden and Chad basins (e.g., Radier, 1959;Greigert, 1966;Kogbe, 1980;Reyment, 1980;Moody and Sutcliffe, 1991). Those series are overlain by fluvial sediments of the Late Eocene-Early Oligocene "Continental Terminal" (Lang et al, 1986(Lang et al, , 1990Chardon et al, 2016;Fig. 2).…”