Sedimentary geochemistry is concerned with chemical investigation of geological processes and materials in low temperature and pressure environments at or relatively close to the Earth’s surface. Eight core sediment samples from offshore exploratory well within part of the Niger Delta, southern Nigeria were investigated for major and trace elements abundances using Proton-Induced X-ray Emission (PIXE) spectroscopy analytical method as well as the determination of the organic matter types. The aims were to investigate the down-hole variation in depositional environment and organic matter type within the studied depth. Most major elements concentration showed high variations in the shale facies. Silicon (SiO2) concentration varied from 20.05 to 40.01%. High Si content (~32-40%) were observed in the sandstones ((litharenite, arkose and wacke) while the low concentration was found in the shales. The elemental contents of Aluminium (Al203) (9.01 to 11.82%) and Iron (Fe203) (0.01 to 4.53%) showed similar trend in the samples, as high Al and Fe content are observed in the shales. The low Sr content observed in all the samples showed diagenetic alteration due to meteoric water rock interaction. The result of the kerogen analysis indicated that the organic matters in the samples were essentially Type III and with few Type II/III organic matters. These are capable of generating mainly gas and waxy crude oil. The slight down-hole variations of the organic matter in the samples probably reflected slight differences in the depositional environments and the degree of organic matter preservation.
Keywords: Kerogen, organic matter, major elements, trace elements, Niger Delta.
PAPER TITLE :DOWN-HOLE GEOCHEMISTRY OF THE CORE SEDIMENTS FROM PART OF THE NIGER DELTA BASIN, SOUTHERN NIGERIA.
FUTA JOURNAL OF RESEARCH IN SCIENCE | VOLUME 14 NUMBER 1 2018
- Author(s) : Akinsanpe, O. T. and Benjamin, U. K.