Organic geochemical characteristics and depositional models of Upper Cretaceous marine source rocks in the Termit Basin, Niger

Upper Cretaceous marine mudstones are widely known as the most important source rocks in the Western African rift basins. However, geochemical studies on their occurrence and formation mechanism are scarce. In this study, a detailed geochemical investigation within a sequence stratigraphic framework...

Full description

Saved in:
Bibliographic Details
Published in:Palaeogeography, palaeoclimatology, palaeoecology palaeoclimatology, palaeoecology, 2018-04, Vol.495, p.292-308
Main Authors: Lai, Hongfei, Li, Meijun, Liu, Jiguo, Mao, Fengjun, Xiao, Hong, He, Wenxiang, Yang, Lu
Format: Article
Language:English
Subjects:
Biomarker
Organic matter
Palaeoenvironment
Sea level
Sequence stratigraphy
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Upper Cretaceous marine mudstones are widely known as the most important source rocks in the Western African rift basins. However, geochemical studies on their occurrence and formation mechanism are scarce. In this study, a detailed geochemical investigation within a sequence stratigraphic framework was carried out to reconstruct the palaeoenvironmental conditions and to establish models on the depositional history of Upper Cretaceous marine mudstones in the Termit Basin (Niger), western African. A total of six third-order sequences (DSQ1, DSQ2, YSQ1, YSQ2, YSQ3 and MSQ1, from bottom to top) were identified in the Upper Cretaceous. The distribution of biomarkers from 33 mudstone samples in different sequences indicate that mudstones from YSQ3 were mainly deposited in a suboxic to oxic environment, with significant contributions from mixed terrigenous higher plants and lower aquatic organisms in fresh-brackish water column. In contrast, the other sequences (YSQ2, YSQ1, DSQ2 and DSQ1) mainly represent a suboxic to anoxic marine environment with a stratified water column (0.59 
ISSN:0031-0182
1872-616X
DOI:10.1016/j.palaeo.2018.01.024