Organic facies and palynofacies: Nomenclature, classification and applicability for petroleum source rock evaluation

Abstract

Abstract The basic aim of the investigation presented in this paper was to determine all relevant petrographical and geochemical characteristics of organic facies and their correlation with the lithological composition, sedimentation conditions and paleoenvironments. Application of geological and geochemical methods gives new insight into problems concerning determination of the potential and efficiency of petroleum source rocks. In making the qualitative and quantitative analyses of organic matter in this study various analytical methods were used (whole rock samples, kerogen concentrates; transmitted and reflected normal and fluorescent light). The type of organic facies was used as a criterion for the identification, accumulation and transformation of the organic matter. Paleobotanical studies of organic facies and palynofacies were used to identify types of vegetation and draw conclusions concerning the sedimentary environment. Various types of organic facies and palynofacies were classified in relation to the origin of the organic matter. All sedimentary organic constituents of continental (huminite/vitrinite, inertinite, cuticle, wood fragments, tracheids, spores and pollen) and marine (mostly autochthonous-dinocysts, algae, foraminifera test linings, acritarchs and amorphous organic matter) origin have been grouped according to different classification systems. A summary of these classifications is proposed, with remarks on approximate corresponding coal macerals and selected kerogen types.