Mineralogical characterization and preliminary assessment of the hydrocarbon potential of sedimentary rock from the western part of the Central Kongo


  • Rajae Bouamoud Laboratory of Materials, Nanotechnologies and Environment (LMNE), Center of Materials, Mohammed V University, Faculty of Sciences
  • Adnane El Hamidi Laboratory of Materials, Nanotechnologies and Environment (LMNE), Center of Materials, Mohammed V University, Faculty of Sciences
  • Mohammed Halim Laboratory of Materials, Nanotechnologies and Environment (LMNE), Center of Materials, Mohammed V University, Faculty of Sciences
  • Raphael Mulongo Masamba Laboratory of Materials, Nanotechnologies and Environment (LMNE), Center of Materials, Mohammed V University, Faculty of Sciences
  • Roger Antoine Kobo Nlandu Center for Geological and Mining Research (CGMR), Department of Geochemistry, Kinshasa
  • Said Arsalane Laboratory of Materials, Nanotechnologies and Environment (LMNE), Center of Materials, Mohammed V University, Faculty of Sciences




In this work, the mineralogical characteristics and the assessment of the petroleum potential of organic carbon-rich sedimentary rock (CK sample) originating from the western part of the Central Kongo were the subject of a preliminary analysis and the results were compared with those of Moroccan oil shales. The mineralogical characterization was carried out using X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), Fourier Transform Infra-Red (FTIR) spectroscopy, Thermal Gravimetry/Differential Thermal Analysis (TG/DTA) and Scanning Electronic Microscopy (SEM-EDX). The results show that the examined sedimentary rock contain a significant part of minerals, about 80%, consisting of quartz, clays and pyrite, similar to those frequently found in oil shales. The pyrolysis also indicates the presence of volatile matter between 250 and 580°C, attributed to the Organic Matter (OM) disseminated within the sedimentary rock as was shown in several carbon-rich materials. The detection of pyrite in the CK sample reveals the existence of a reducing environment during the preservation period of OM in the source rock. The assessment of the petroleum potential using the basic Rock-Eval method associated with the elemental analysis and 13C Cross Polarization/Magic Angle Spinning Nuclear Magnetic Resonance (13C CP/MAS NMR) spectroscopy indicated a very good organic richness (TOC=10.77%), very good petroleum potential (S2=80.4 mgHC/g rock) with the sapropelic OM described as type I kerogen (H/C molar ratio of 1.71) characterized by high hydrogen index (HI=746 mgHC/g TOC) and low oxygen index (OI=13 mgCO2/g TOC) values. The Rock-Eval results were confirmed by 13C CP/MAS NMR spectroscopy which shows the exclusive presence of aliphatics. The mineralogical and petroleum characteristics of CK sample show a great resemblance with those of known oil shales such as Moroccan oil shales and its kerogen is probably related to a marine or lacustrine environment which formed in anoxic sedimentary rocks and with a thermal evolution that has just reached the early stage of the oil window

Author Biographies

Rajae Bouamoud, Laboratory of Materials, Nanotechnologies and Environment (LMNE), Center of Materials, Mohammed V University, Faculty of Sciences

Department of chemistry, PhD student

Adnane El Hamidi, Laboratory of Materials, Nanotechnologies and Environment (LMNE), Center of Materials, Mohammed V University, Faculty of Sciences

Professor, Department of chemistry

Mohammed Halim, Laboratory of Materials, Nanotechnologies and Environment (LMNE), Center of Materials, Mohammed V University, Faculty of Sciences

Professor, Department of chemistry

Raphael Mulongo Masamba, Laboratory of Materials, Nanotechnologies and Environment (LMNE), Center of Materials, Mohammed V University, Faculty of Sciences

PhD Student, Department of chemistry

Said Arsalane, Laboratory of Materials, Nanotechnologies and Environment (LMNE), Center of Materials, Mohammed V University, Faculty of Sciences

Professor, Department of Chemistry


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Petroleum Chemistry