Hydrocarbon Potential of the Middle–Late Jurassic Series of Northwestern Iraq: A Case Study in the Shaikhan Oil Field

  • Swar J. Al-Atroshi Department of Geology, College of Science, Salahaddin University Erbil, Erbil, Kurdistan Region- F. R. Iraq
  • Govand Husain Sherwani Department of Civil Engineering, College of Engineering, Cihan University-Erbil, Erbil, Kurdistan Region- F. R. Iraq http://orcid.org/0000-0001-5986-7061
  • Srood F. Al-Naqshbandi Department of Geology, College of Science, Salahaddin University Erbil, Erbil, Kurdistan Region- F. R. Iraq
Keywords: Middle-Late Jurassic, Rock-Eval, Biomarker, Burial history, Shaikhan oilfield

Abstract

The Middle–Late Jurassic Sargelu, Naokelekan, and Barsarin formations of northwestern Iraq have been investigated in the Shaikhan oilfield (well Shaikhan-8) to assess their potential for hydrocarbon generation.The results of total organic carbon analysis and rock-eval pyrolysis revealed a good-to-excellent hydrocarbon content and suggest that the depositional conditions were suitable for the production and preservation of organic matter. The thermal maturity proxy indicates that the studied formations were at the start of the hydrocarbon generation period. Most of the samples from the Sargelu and Barsarin formations belong to kerogen type II, whereas those of the Naokelekan Formation belong to kerogen type II/III. The Pr/Ph, Pr/n-C17, and Ph/n-C18 ratios of the extracted bitumen indicated that the organic matter originated from marine sources under reducing conditions. The stable carbon isotope composition of the saturated and aromatic hydrocarbon fractions ranged from –28.3 to –27.7 ‰ and –28.0 to –27.7 ‰, respectively. The biomarker results show a high contribution of marine organic matter that was preserved under relatively anoxic conditions. The profiles of the burial and thermal maturity history show that the simulated generation zones, based on the calculated vitrinite reflectance, indicate immature (0.44%–0.6%)-to-early oil generating (0.6%–0.75%) source rock. The low thermal maturity of the studied formations relative to the depth may be attributed to the low geothermal gradient and heat flow.

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Author Biographies

Swar J. Al-Atroshi, Department of Geology, College of Science, Salahaddin University Erbil, Erbil, Kurdistan Region- F. R. Iraq

Dr. Swar was born in 1964 in Sulaimani- Iraq, and awarded his PhD. in Petroleum Geology in 2019, from Salahaddin University- Erbil, M.Sc. in Petroleum Geology (1999) from Baghdad University-Iraq and B.Sc. in Geology (1987), from Salahaddin University-Erbil. His major research interests are: Stratigraphy and Petroleum Geology. He was assigned to various administrative and academic posts during over 20 years of experience in Salahaddin University- Erbil. Currently, he works as a Lecturer at Department of Geology, Salahaddin University- Erbil, Iraq.

Govand Husain Sherwani, Department of Civil Engineering, College of Engineering, Cihan University-Erbil, Erbil, Kurdistan Region- F. R. Iraq

Dr. Sherwani was born in 1958 in Kirkuk- Iraq and was awarded his PhD. in Petroleum Geology in 1998, M.Sc. in Geology (1983), and B.Sc. in Geology (1980), all from Baghdad University- Iraq. His major research interests are: Stratigraphy, Sedimentology, and Petroleum Geology, and published over 50 scientific papers and reports. He was assigned to various administrative and academic posts during over 36 years of experience and worked in several Iraqi academic institutions, such as Baghdad and Salahaddin Universities. Currently, he works as a Lecturer in Cihan University- Erbil, Iraq.

Dr. Sherwani worked as a part-time consultant for several state and private institutions such as Ministry of Industry-KRG (2000-2004), Iraqi HC Research Group -Oklahoma University (2004-2005), Consultant Geologist - UN-FAO (2001-2003), and Petroleum Consultant - Heritage Oil Company (2005-2007).

Srood F. Al-Naqshbandi, Department of Geology, College of Science, Salahaddin University Erbil, Erbil, Kurdistan Region- F. R. Iraq

Dr. Naqshabandi was born in 1958 in Erbil- Iraq and was awarded his PhD. in Palynology and Organic Matters in 1999 from Baghdad University, M.Sc. in Geology (1988) from Salahaddin University, and B.Sc. in Geology (1981) from Sulaimani University. His major research interests are Palynostratigraphy, Stratigraphy, and Petroleum Geology, published over 15 scientific papers.

He was assigned to several managerial and academic posts during over 38 years of experience and worked in several Iraqi academic institutions, such as Tishik and Salahaddin Universities. Currently, he is an assistant professor in the Department of Geology, College of Science, Salahaddin University.

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Published
2020-12-31
How to Cite
Al-Atroshi, S., Sherwani, G., & Al-Naqshbandi, S. (2020, December 31). Hydrocarbon Potential of the Middle–Late Jurassic Series of Northwestern Iraq: A Case Study in the Shaikhan Oil Field. UKH Journal of Science and Engineering, 4(2), 48-64. https://doi.org/https://doi.org/10.25079/ukhjse.v4n2y2020.pp48-64
Section
Research Articles
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