New Findings in Applied Geology

New Findings in Applied Geology

Organic petrography and geochemistry of the Upper Devonian black shales in north of Kerman (south of the Central-East Iranian Microcontinent) and evaluation of their hydrocarbon generation potential

Author
Amir Hossein Rahiminejad
Assist. Prof., Dept., of Ecology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran
10.22084/nfag.2025.30510.1657
Abstract
Generally, few studies have been carried out on the organic petrographic and organic geochemical aspects of Devonian black shales in Iran. This paper is focused on the organic petrography, organic geochemistry and hydrocarbon generation potential of six intervals (with a total thickness of 44.5m) of black shales in an Upper Devonian stratigraphic succession of the Bahram Formation in the north of the city of Kerman. Stratigraphically, the Bahram Formation in the studied area contains one the thickest interval of Upper Devonian black shales in the central Iran. Based on detailed organic petrographic analysis, the organic materials in the studied black shale intervals derived from the land and inertinite is the only maceral identified in the intervals. The inertinite reflectance in the shale intervals ranges from 1.56 to 3.37 and the TAI ranges between+4 and- 4. Additionally, the total organic carbon (TOC) in the black shale intervals ranges from 0.76 (wt %) to 2.79 (wt %). The organic petrographic evidence and the organic geochemical diagrams show that the studied organic materials are highly mature and they display kerogen type IV. This research proposes that the investigated black shale intervals in the Bahram Formation have low hydrocarbon generation potential. However, the black shale inetrvals have limited gas generation potential and tend to the dry-gas prone area.
Keywords
Bahram Formation
Upper Devonian
Black shale
Sedimentology
Stratigraphy
Adeyilola, A., Zakharova, N., Liu, K., Gentzis, T., Carvajal-Ortiz, H., Ocubalidet, S., Harrison III, W. B. (2022) Hydrocarbon potential and organofacies of the Devonian antrim shale, Michigan basin. International Journal of Coal Geology, 249: 103905. https://doi.org/10.1016/j.coal.2021.103905.
Baioumy, H., Ulfa, Y., Nawawi, M., Padmanabhan, E., Anuar, M. N. A. (2016) Mineralogy and geochemistry of Palaeozoic black shales from Peninsular Malaysia: Implications for their origin and maturation. International Journal of Coal Geology, 165: 90–105.
Behar, F., Beaumont, V., Penteado, H. D. B. (2001) Rock-Eval 6 technology: performances and developments. Oil & Gas Science and Technology. 56 (2): 111–134.
Boyer, D. L., Droser, M. L. (2009) Palaeoecological patterns within the dysaerobic biofacies: Examples from Devonian black shales of New York state. Palaeogeography, Palaeoclimatology, Palaeoecology, 276 (1–4): 206–216.
Carvalho, M. A., Mendoca Filho, J. G., Menezes, T. R. (2002) Palynofacies analysis of the upper Aptian-Albian succession of Sergipe Basin, Brazil. In Boletim 6_ simposio sobre o Cretaceo do Brasil, Sao Pedro-SP, p. 209–214.
Fathy, D., Baniasad, A., Littke, R., Sami, M. (2024) Tracing the geochemical imprints of Maastrichtian black shales in southern Tethys, Egypt: Assessing hydrocarbon source potential and environmental signatures. International Journal of Coal Geology, 283: ­104457. https://doi.org/10.1016/j.coal.2024.104457.
Flügel, E. (2010) Microfacies of carbonate rocks, analysis interpretation and application, Springer, Berlin, 984p. https://doi.org/10.1007/978-3-642-03796-2.
Gholamalian, H. (2006) Biostratigraphy of Late Devonian Sequence in Hutk section (North of Kerman) Based on Conodonts. Geosciences Scientific Quarterly Journal (Ulum-I Zamin), 15 (59): 94–101. (in Persian).
Hashmie, A., Rostamnejad, A., Nikbakht, F., Ghorbanie, M., Rezaie, P., Gholamalian, H (2016) Depositional environments and sequence stratigraphy of the Bahram Formation (middle–late Devonian) in north of Kerman, south-central Iran. Geoscience Frontiers, 7(5): 821–834.
Hunt, J. M. )1996( Petroleum geochemistry and geology, W. H. Freeman, New York, 743p.
Ju, Y., Wang, G., Bu, H., Li, Q., Yan, Z. (2014) China organic-rich shale geologic features and special shale gas production issues. Journal of Rock Mechanics and Geotechnical Engineering, 6(3): 196–207. https://doi.org/10.1016/j.jrmge.2014.03.002.
Klemme, H. D., Ulmishek, G. F. (1991) Effective petroleum source rocks of the world: stratigraphic distribution and controlling depositional factors. AAPG Bulletin, 75(12): 1809–1851.
Li, Y., Fan, T., Zhang, J., Wei, X., Zhang, J. (2015) Impact of paleoenvironment, organic paleoproductivity, and clastic dilution on the formation of organic-rich shales: a case study about the Ordovician-Silurian black shales, southeastern Chongqing, South China. Arabian Journal of Geosciences, 8(12): 10225–10239. https://doi.org/10.1007/s12517-015-1944-y.
Mahmudy Gharaie, M. H., Matsumoto, R., Racki, G., Kakuwa, Y. (2007) Chemostratigraphy of Frasnian-Famennian transition: Possibility of methane hydrate dissociation leading to mass extinction, in Monechi, S., Coccioni, R., and Rampino, M., eds., Large Ecosystem Perturbations: Causes and Consequences. Geological Society of America Special Papers, 424: 109–125.
Melendez, R. B. (2001) The characterisation and combustion of South American coals. PhD Thesis, University of Nottingham.
Mendonça Filho, J. G., Menezes, T. R., Mendonça, J. D. O. (2011) Organic composition (palynofacies analysis). ICCP Training Course on Dispersed Organic Matter, 5: 33–81.
Menezes, T. R., Mendonça Filho, J. G., Araujo, C. V., de Souza, I. V. A. F., de Oliveira Mendonça, J. (2008) Fácies orgânica: conceitos, métodos e estudos de casos na indústria do petróleo. Brazilian Journal of Geology, 38(2): 86–96.

Mirshahani, M., Khani, B., Khajehzadeh, A (2017) Applied Organic Petrography: Principals and Techniques . Research Institute of Petroleum Industry (RIPI), Tehran, 328p. (in Persian).

Nichols, G (2009) Sedimentology and Stratigraphy. Wiley– Blackwell, Chichester, 432 p.
Pang, Q., Song, H., Xu, Z., Xu, S., Hu, G., Liu, Y., Zhang, J. (2024) Uranium mobility and enrichment during hydrocarbon generation and accumulation processes: A review. Ore and Energy Resource Geology: 100063. https://doi.org/10.1016/j.oreoa.2024.100063.
Pearson, D. L. (1990) Pollen/spore color “standard,” version 2. Phillips Petroleum eology Branch, Bartlesville, Oklahoma, 3p.
Peters, K. E. (1986) Guidelines for evaluating petroleum source rock using programmed pyrolysis. AAPG bulletin, 70(3): 318–329.
Potter, P. E., Maynard, J. B., Depetris, P. J. (2005) Mud and Mudstone: Introduction and overview. Springer-Verlag, Berlin, 297pp. https://doi.org/10.1007/b138571.
Qiuying, Z. (2000) Uraniferous Black Shale and Related Uranium Mineralization Features in South China. Acta Geologica Sinica, 74 (3): 602–604.
Rahiminejad, A. H., Zand-Moghadam, H., Mirshahani, M., Khajehzadeh, A. (2022) Famennian inertinite-bearing marine shale facies as indicator of wildfire event in north of Gondwana. Historical Biology, 34(9): 1752–1768.
Reading, H. G. (Ed) (1996) Sedimentary Environments: Processes, Facies and Stratigraphy. Wiley-Blackwell, Oxford, 704p.
Staplin, F. L. (1969) Sedimentary organic matter, organic metamorphism, and oil and gas occurrence. Bulletin of Canadian Petroleum Geology, 17 (1): 47–66. https://doi.org/10.35767/gscpgbull.17.1.047.
Stocklin, J. (1974) Possible ancient continental margins in Iran. In: Burk, C.A., & Drake, C.L. (Eds). The geology of Continental margins. Springer-Verlag, Berlin and Heidelberg, pp. 873–887.
Takin, M. )1972( Iranian geology and continental drift in the Middle East. Nature, 235(5334): 147–150. https://doi.org/10.1038/235147a0.
Taylor, G. H., Teichmüller, M., Davis, A. C. F. K., Diessel, C. F. K., Littke, R., Robert, P. (1998) Organic petrology. Gebrüder Borntraeger, Berlin, 704 p.
Trabucho-Alexandre, J., Hay, W. W., De Boer, P. L. (2012) Phanerozoic environments of black shale deposition and the Wilson Cycle. Solid Earth, 3(1): 29–42. https://doi.org/10.5194/se-3-29-2012, 2012.
Tyson, R. V. (1993) Palynofacies analysis. In Applied micropalaeontology, Springer, Dordrecht, p. 153-191. Netherlands. https://doi.org/10.1007/978-94-017-0763-3_5.
Tyson, R. V. (1995) Abundance of organic matter in sediments: TOC, hydrodynamic equivalence, dilution and flux effects. In: Sedimentary organic matter:­ Organic facies and palynofacies. Springer, Dordrecht, (pp. 81-118). https://doi.org/10.1007/978-94-011-0739-6_5.
Vahdati-Daneshmand, F., Mosavvari, F., Mahmudi Gharai, M. H., Ghasemi, A (1995) Geological map of Zarand, Geology Survey of Iran, Tehran, scale: 1:100,000 series, sheet 7351.
Wang, E., Guo, T., Li, M., Xiong, L., Dong, X., Wang, T., Ouyang, J. (2023) Reservoir characteristics and oil properties of a lacustrine shale system: Early Jurassic black shale from the Sichuan Basin, SW China. Journal of Asian Earth Sciences, 242: 105491.https://doi.org/10.1016/j.jseaes.2022.105491.
Wendt, J., Kaufmann, B., Bełka, Z., Farsan, N., Bavandpur, A. K. (2002) Devonian/lower carboniferous stratigraphy, facies patterns and palaeogeography of Iran. Part I. Southeastern Iran. Acta Geologica Polonica, 52(2): 129–168.
Wilmsen, M., Fürsich, F. T., Seyed-Emami, K., Majidifard, M. R. (2009) An overview of the stratigraphy and facies development of the Jurassic System on the Tabas Block, east-central Iran. In: Brunet, M.F., Wilmsen, M., & Granath, J.W. (Eds), South Caspian to central Iran basins. Geological Society, London, Special Publications, 312 (1): 323–343. https://doi.org/10.1144/SP312.15.

  • Receive Date 07 February 2025
  • Revise Date 10 April 2025
  • Accept Date 13 April 2025