Comparative study between Rock-Eval pyrolysis and biomarkers parameters: A case study of Horn Valley Siltstone source rock in central- Australia

In this study 44 Sedimentary rock samples from the Amadeus Basin, in southern portion of the Northern Territory, Australia, were analyzed by two well-proven organic geochemical Rock-Eval (RE) pyrolysis and gas chromatography–mass spectrometry (GC–MS) analysis. These techniques were used to obtain independent parameters on organic matter composition, its thermal maturity, and environment of deposition. This study reveals a close concordance between Rock-Eval pyrolysis data and polycyclic biomarkers parameters such as steranes.RE pyrolysis in conjunction with GC–MS analysis show that the Amadeus Basin sediments contain a variable but notable organic-rich facies in the Horn Valley siltstone and prove an unequivocal evidence for Type-II organic matter, which lies dominantly to the peak stage of the conventional oil window (end of diagenesis-middle of catagenesis). The case study from the Amadeus Basin shows that these methods remain undoubtedly suitable for a good assessment of the petroleum potential of source rocks and rapid geochemical characterization of sedimentary organic matter, and can be used in other similar basins.