TITLE:
Provenance of Ypresian to Miocene Sediments of the Ader Doutchi in the Akoumoutt Area, Paleoenvironment and Tectonic Context (Ader Doutchi Sub-Basin, Niger)
AUTHORS:
Aminou Abdoulaye Maâzou, Zikpi Yawovi Amoudji, Moussa Konaté
KEYWORDS:
Niger, Tahoua, Iullemmeden Basin, Sedimentology, Geochemistry, Paleogene
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.14 No.1,
January
22,
2026
ABSTRACT: A multidisciplinary approach was used for studying the upper detrital series of the Iullemmeden Basin, which crop out in the central part of the Ader Doutchi Sub-Basin (Akoumoutt Sector). This approach includes sedimentological and geochemical analyses, involving XRF analysis of major and trace elements. The aims of this study consist to: 1) determine the provenance of the Ypresian to Miocene in age sediments of the Ader Doutchi sub-basin; 2) define their tectonic context; and 3) identify the paleoenvironment in which they were deposited. Preliminary facies analysis revealed the presence of clays, oolites, iron-rich sandstones, and in some cases, pyrite. Termitic tubing have occasionally been observed in these deposits. Geochemical analysis that specific Ader Doutchi (Ct1) formation deposits are derived from mafic to intermediate igneous rocks of the active continental margin. It is hypothesized that some of these rocks are felsic and constitute remnants of an island arc that underwent fragmentation. The sediments supply from this are derived from the terranes of the Tuareg Shield. The studied sediments exhibit higher aluminium oxide (Al2O3) and iron oxide (Fe2O3) concentration than the UCC and PASS, while silicon oxide (SiO2) levels are lower. The values obtained for different chemical indexes (CIA, PIA, CIW, and ICV) indicate that the sediments are mature and have undergone significant fractionation and weathering. The sediments were deposited in a variety of environments, including marine, marginal littoral, and continental settings. The environmental conditions alternated between oxidizing and anoxic states. The region’s climate exhibited significant variability, oscillating from hot to humid conditions to hot and arid conditions, with a marked tendency to aridification.