Reconstructing the late Permian-early Triassic environment of a coal-bearing succession in the Maniamba Basin, Mozambique (Central Gondwana): A multiproxy palynological and geochemical approach

IF 5.6 2区工程技术 Q2 ENERGY & FUELS

International Journal of Coal Geology Pub Date : 2025-03-28 DOI:10.1016/j.coal.2025.104755

N. Nhamutole , M.K. Bamford , P.A. Souza , C.M. Felix , E. Pereira , L. Bastos , L. Mendes , O. Deus , M. Nopeia , D.A. Carmo

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引用次数: 0

Abstract

The Maniamba Basin is an intracratonic, Karoo-aged basin located in northern Mozambique. Recent studies have reported the occurrence of organic-rich units in the Maniamba Basin, based on Rock Eval data. However, detailed characterization of the palaeoenvironments in the basin is still lacking. In this study, detailed palynological, palynofaciological, XRD and organic geochemical techniques (TOC, total sulphur, and biomarkers) were performed in order to understand past environments that prevailed in the basin. The palynological data reveal the dominance of gymnosperm taxa (striate and non-striate bisaccate, and praecolpate pollen grains) followed by lycopsids, sphenopsids and ferns suggesting hypautochthonous sedimentation characterized by warm and humid palaeoclimate. The palynological results indicate a Permian and Triassic age for the strata. The organic-rich units unveiled a dominance of phytoclasts and palynomorphs, and to a lesser extent by terrestrial and bacterially derived organic matter with no fluorescence, indicating high maturity. Swamp, river and lake dominated environments with oxic-suboxic-anoxic conditions, reflecting shifting of depositional conditions overtime, are inferred in the Maniamba Basin. The deposition and accumulation of organic-rich units were mainly controlled by palaeoredox conditions linked to basin infill during different rifting episodes. The biomarkers mainly consist of saturated compounds that suggest terrestrial organic matter with freshwater algal contribution.

Overall, the integration of mineralogical composition with palynofacies, biomarkers and palynology indicate the presence of potential source rocks that were thermally influenced. Additionally, the petroleum fluids known from younger strata in the Rovuma and Mozambique basins did not show any link with the source rock reported previously.

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来源期刊

International Journal of Coal Geology 工程技术-地球科学综合

CiteScore

11.00

自引率

14.30%

发文量

145

审稿时长

38 days

期刊介绍： The International Journal of Coal Geology deals with fundamental and applied aspects of the geology and petrology of coal, oil/gas source rocks and shale gas resources. The journal aims to advance the exploration, exploitation and utilization of these resources, and to stimulate environmental awareness as well as advancement of engineering for effective resource management.