Provenance and paleoenvironment of organic matter within the Fika sediments in Chad (Bornu) Basin, northeastern Nigeria: An integrated organic geochemical and palynofacies approach

Biomarker distributions and palynofacies data provide evidence for a mixed aquatic algae and terrigenous organic matter input deposited in a marginally marine, moderate salinity, proximal setting with a strong influx of terrestrial plant under environmental conditions that were mostly suboxic. Compound specific isotopic analysis of n-alkanes fraction were also used for the paleoenvironmental inferences. The flat portion pattern of the n-alkane profile between n-C21 and n-C26 in Fika samples is an indication of marine environment and it shows that Fika sediments consist of both terrestrial and marine organic matter deposited in fluvial/deltaic to shallow marine settings.