Regressive Shoreface Depositional System of the Cretaceous Yolde Formation of the Gongola Sub-Basin Northern Benue trough N. E. Nigeria

Abstract

<jats:p>The characterization of lithofacies of the Yolde Formation at Briyel town in the Gongola Sub-basin of the Northern Benue Trough indicated coarsening upwards cycles composed transitional succession of six lithofacies that comprises of trough cross-beds, planar cross-beds, massive beds, ripple laminations, parallel laminations and mudstone. This coarsening and thickening upward symmetry is defined by a densely bioturbated mud dominated lower part transitionally grading into heterolithic interval composed thinly bedded sandstone and mudstones both of which developed below fair-weather wave base. This is capped by a succession of moderately bioturbated trough-planar crossbedded sandstone with poly-directional paleocurrent system. These assemblages reflect shoreface deposits and devoid of hummocky cross-stratification therein may account for a moderate wave oceanographic system. Evolution of this setting in the Gongola Sub-basin is indicative of a scenario of a broaden coastline in the coastal palaeogeography of the Yolde Formation typically suppressing due to frictional damping.</jats:p>

Mineralogy and Geochemistry of Shale Deposits in the Lower Anambra Basin, Nigeria: Implication for Provenance, Tectonic Setting and Depositional Environment

“…Sedimentary geochemical data has been demonstrated to provide critical information for provenance studies through the analysis of major, trace, and rare earth elements (REEs) as well as their ratios in sedimentary rocks, which can simulate climatic, geographical, and tectonic conditions of the basins (Bhatia, 1983;Taylor and McLennan, 1985;Bhatia and Crook, 1986;McLennan, 1989;Feng and Kerrich, 1990;McLennan and Taylor, 1991;Cullers, 1994;Jahn and Condie, 1995;Girty et al, 1996;Etemad-Saeed et al, 2011;Verma and Armstrong-Altrin, 2013;Obaje et al, 2020;Waziri et al, 2020;Musa et al, 2022). Therefore, detailed studies of the geochemistry and mineralogy of fine-grained clastic sedimentary rocks is regarded as a valuable tool for determining provenance, tectonic setting, paleoweathering, and redox condition of a given source location (Ruffell et al, 2002;Ahlberg et al, 2003;Deconinck et al, 2005;Dera et al, 2009;Shettima et al, 2020a;Shettima et al, 2020b). Anambra Basin located in the southern part of Nigeria lies between the southern portion of the Benue Trough and the Niger Delta (Fig.…”