TITLE:
Diagenetic and Geochemical Study of Sediments from the Cretaceous Basin of Babouri-Figuil (North-Cameroon)
AUTHORS:
Augustin Désiré Balla Ondoa, Alexis Nyangono Abolo, Léopold Ekengele Nga, Appolinaire Tograne, Simon Ngos III, Elvine Paternie Edjengte Doumo, Armel Zacharie Ekoa Bessa
KEYWORDS:
Diagenesis, Geochemistry, Cretaceous Sediments, Babouri-Figuil Basin, Sedimentary Basin
JOURNAL NAME:
International Journal of Geosciences,
Vol.12 No.4,
April
29,
2021
ABSTRACT: The purpose of this work is to characterize the sediments of the
Babouri-Figuil Basin from a diagenetic point of view, the
protolith context and weathering conditions, using
major element geochemistry and mineralogy of the sedimentary rocks. Microscopic
observations of diagenetic phenomena (on and around detrital grains of the
basin), and the study of precipitation of the cement show that these sediments
have undergone phenomena of compaction, dissolution, recrystallization and
cementation. Cementation of quartz by silica is controlled by the rate of precipitation
of silica, which is closely related to temperature than pressure. Thus, the
sediments of the basin could be influenced by hydrothermalism during
diagenesis, which would have inhibited their reservoir quality by generalized
cementation phenomena. Geochemical features of the sediments show high contents
in SiO2 (47.49 wt% - 90.79
wt%), Al2O3 (2.92 wt% - 23.18 wt%), Fe2O3 (0.2 wt% - 6.22 wt%) and alkali and alkaline earth metals (>3%). The chemical
alteration index varies between 30.92% and 95.08%. This variation in the CIA
values reflects the variation in the proportion of feldspars and different clay
minerals in these sediments. However, the ICV calculation
and the ICV versus CIA show compositional immature to mature sediments, with low to intense weathering character of these
sediments. Petrographic and geochemical
characteristics of sediments of the basin are compatible with the composition of the granitic and gneissic surrounding bedrocks.