Therefore, the quantity, quality and thermal maturation of source rocks are pivotal in petroleum exploration. This yields biomarkers from both aliphatic and aromatic fractions that could be utilized to deduce organic source input, paleoredox condition, maturity, and age determination as well as relating their provenance (Peters et al. Most geochemical analyses rely heavily on data obtained from bitumen extraction. The composition and long-term preservation of organic matter deposited in the marine domain throughout the Orange Basin is related to deposition system stacking and, as a result, the depositional systems tracts in which it was deposited (Adekola et al. A thorough geochemical analysis of source rocks can reveal information about the hydrocarbons they produce (Adekola et al. Organic geochemistry is an important tool for identifying source rocks and classifying crude oils into families both at the beginning and later stages in oil exploration (Peters et al. According to Jungslager ( 1999) and Van der Spuy ( 2003), the Orange Basin has primarily three source rock intervals. There have been some reports on the geochemical attributes of source rocks from the Orange Basin (Jungslager 1999 Van der Spuy 2003). The huge Ibhubesi gas reserve off South Africa as well as the Kudu gas field in South Namibia are the result of ongoing hydrocarbon prospecting (PASA 2003). As a result, the extrapolated crustal processes are directly analogous to the genesis and evolution of the Orange Basin, demonstrating Gondwana’s breaking up and the opening of the Atlantic Ocean Margin.ĭuring the last thirty years, the South African government has been motivated to explore the Orange Basin due to the discovery of valuable petroleum on the southern Atlantic margins (Jungslager 1999 Hartwig et al. Geochemical figures on tectonic setting discriminant function diagrams revealed a continental rift of passive margin settings. The investigated sediments are made up of intermediate igneous rocks that have undergone moderate chemical weathering. This is congruent with biomarker and isotope analyses that further indicate the presence of marine-derived source rocks with some terrestrial remains generating hydrocarbons. According to the V/Ni ratio, samples from the Orange Basin in South Africa are mainly anoxic, with only a few samples ranging from suboxic to anoxic. Based on various biomarker proxies and vitrinite reflectance data, some samples are thermally mature to produce petroleum, while others are not. The source rocks accumulated in a reduced, anoxic, saline water column. Molecular analyses of both aliphatic and aromatic compounds reveal an input dominantly from a marine source. Aptian to Campanian sediments from the Western offshore to Central Orange Basin were studied by integrating molecular geochemistry, inorganic and isotopic studies to recognize their geochemical characteristics via the reconstruction of the Orange basin’s paleoweathering, paleosalinity, paleovegetation, paleoclimate, and tectonic records.