A Comparative Sedimentology of the Cross River and Qua-Iboe River Estuarine Systems, Southeast Coast of Nigeria

Abstract

Cross River and Qua-Iboe river estuaries occur on the eastern flank of the Niger Delta, which is globally recognized as one of the most prolific petroleum producing basins in the world. Despite their importance, there is sparse literature concerning their sedimentology and stratigraphy in the public domain. The goal of this present study is to provide a detailed sedimentological investigation of the Cross River and Qua-Iboe River estuaries. Surficial samples have been collected at 50 georeferenced sites throughout each of these estuaries using a Van-Veen grab sampler. Six core samples, representing the upper, middle and lower portions of each estuary have also been obtained using a gravity corer. Depth measurements were made using a single beam echo sounder from an outboard motor boat. Flow measurements are being carried out over spring, mean and neap tidal cycles. Laboratory analyses will include sieve size analysis, carbon-14 dating of core samples, geochemical assessment of heavy minerals, as well as aeromagnetic data analyses. Results obtained from sieve size analysis will aid in the characterization of the sediments into lithologic facies. Dated core samples will be used to estimate the rate of sedimentation within the estuaries. Geochemical assessment of heavy minerals will provide information on sediment provenance and transportation history. Analyzed aeromagnetic data will be used to evaluate the depth to basement within the studied channels. This will aid in the computation of sediment thickness, which, in conjunction with results of the sieve size analysis, is important in inferring the crude oil bearing potentials of the studied channels. Expected outcomes will include bathymetric maps, tidal current profiles of the estuaries for Spring, Mean and Neap tides as well as spatial and vertical distribution of grain size statistical parameters, bedforms, heavy mineral content and lithologic facies within the estuaries. Results obtained will provide useful indices for paleoenvironmental interpretations of their ancient analogues in the rock record.

AAPG Datapages/Search and Discovery Article #90351 © 2019 AAPG Foundation 2019 Grants-in-Aid Projects