jzs-10773

Organic geochemical and petrographical characteristics of the lower part of Sarmord Formation, M-2 Well, Miran Oil Field, Kurdistan, NE Iraq: Implications for hydrocarbon generation potential and thermal maturation

 Sardar S. Fatah1, Danyar A. Salih1, Stavros Kalaitzidis2, Ibrahim M. J. Mohialdeen1 and Polla A. Khanaqa3

1 Department of Geology, College of Science, University of Sulaimani, Sulaimani, Kurdistan Region- Iraq

2 Department of Geology, University of Patras, 26504 Rio-Patras, Greece

3 Kurdistan Institution for Strategic Studies and Scientific Research, Sulaimani, Kurdisatn Region- Iraq

Original: 3 November 2019       Revised: 28 December 2019      Accepted: 30 January 2020         Published online: 20 June 2020  

Doi Link; https://doi.org/10.17656/jzs.10773

Abstract

The Lower Cretaceous Sarmord Formation (Hauterivian–Barremian) has been investigated in this study. The selected M-2 Well is one of the wells belonging to Miran block, Sulaimani Governorate, Kurdistan Region of Iraq. The area of interest is situated in the High Folded Zone, Western Zagros Fold-Thrust Belt, being approximately 30 km far from Sulaimani City towards the northwest direction. The selected samples were analyzed by Rock-Eval pyrolysis, infrared spectroscopy, and also studied microscopically to determine the quality and quantity of organic matter, the level of thermal maturity, as well as the hydrocarbon generation potentiality. Rock-Eval pyrolysis data show that the total organic carbon for Sarmord Formation is between 0.83 wt.% to 1.55 wt.%, with an average value of 1.27 wt.%. The average and range of S1, S2, and genetic potential (S1+S2) are: 0.76 (0.55–1.09) mg HC/g rock, 0.82 (0.65 – 1.28) mg HC/g rock, and 1.58 (1.21 -2.37) mg HC/g rock, respectively. The average value of pyrolysable carbon (PC) and residual carbon (RC) are of 0.23 wt.% and 1.04 wt.%, respectively. The hydrogen index (HI) is between 47 and 98, with an average value of 66. The obtained data indicate that the Sarmord Formation has a satisfiable range of total organic carbon content, but the organic matter by itself has poor potential to generate hydrocarbons because of low amount of S2, HI, and PC. The Rock-Eval maturity parameters (Tmax and PI ) are undependable in this study. Because they are out of the acceptable range. The cutting samples in this well have been contaminated by solid drilling additives, which were identified during the petrographiocal study by their structure and low reflectance values. The double peaks of S2, solid drilling additives, are affected of disturbing maturity parameters of Rock-Eval data. The petrographic study proved that the samples mostly contain bituminite, which is disseminated predominantly within the clayey particles, with minor amounts of alginite. Additionally, weathered and degraded humic particles are interpreted as content of drilling mud. The kerogen types are mostly of Type II kerogen, because the vitrinite macerals are absent and we have an indication of alginite; which is one of precursos of formation of bituminite. This result is controversial with the graphical presentation of kerogen type by Rock-Eval and infrared microscopy, as they are interpreted as Type III gas-prone kerogen. The equivalent vitrinite reflectance for the studied section ranges between 0.73-0.81%, with the values close to 0.80% being more accurate as were measured in homogenous solid bitumens. The obtained values indicate maturation within the oil window. While based on infra red spectroscopy, maturation is between 0.80 to 1.10, suggesting to higher maturation level compared to vitrinite reflectance values.

Key Words: Sarmord Formation, Kurdistan, Miran Field, Hydrocarbon potentiality, Kerogen type.

      References

[1] Abdula, R. A., "Source Rock Assessment of Naokelekan Formation in Iraqi Kurdistan". Journal of Zankoy Sulaimani-Part A (Pure and Applied Sciences), Vol. 19, pp. 103-124. (2017).

[2] Ahmed, S. H., "Sedimentology of Sarmord Formation from Selected Sections in Sulaimani province Kurdistan Region-NE Iraq". M.Sc. Thesis, University of Sulaimani, Kurdistan Region-Iraq. pp. 83. (2007).

[3] Ahmed, S. H., "Tectonostratigraphic evolution of the northeastern Arabian Plate in Kurdistan since the Jurassic", Ph.D. dissertation, Pierre and Marie Curie University (UPMC) Paris, France. pp. 467. (2013).

[4] Ahmed, S. H., Barrier, E., and Muller, C., "Basin evolution model during cretaceous in the northeastern of Arabian plate in Kurdistan region". Arabian Journal of Geosciences, Vol. 9, No. 14, pp. 645-668. (2016).

[5] Ahmed, S. H., Fattah, A, I., and Namiq, A., "Surface and sub-surface study to interpret the paleo basin morphology during Hauterivian-Albian in Kurdistan Region and North-Iraq". Journal of Zankoy Sulaimani, special issue, Geokurdistan. pp. 229-247. (2016).

[6] Ahmed, S. H., Qadir, B, Q., Muller, C., "Age determinations of Cretaceous sequences based on calcareous nannofossils in Zagros Thrust and Folded Zone in Kurdistan Region-Iraq". Journal of Zankoy Sulaimani, Part A (Pure and Applied Sciences), Vol. 17, No. 3, pp. 185-195. (2015).

[7] Akinlua, A., Ajayi, T. R., Jarvie, D. M., and Adeleke, B. B., "A re-appraisal of the Application of Rock-Eval Pyrolysis to Source Rock Studies in the Niger Delta". Journal of Petroleum Geology, Vol. 28, No. 1, pp. 39 - 48. (2005).

[8] Al-Ameri, Th, K., Najaf, A, A., Al-Khafaji, A, S., Zumberge, J., Pitman, J., "Hydrocarbon potential of the Sargelu Formation, North Iraq". Arabian Journal of Geosciences. DOI 10.1007/s12517-013-0875-8. (2013).

[9] Alaug, A. S., Mahmoud, M. S., Deaf, A. S., and Al-Ameri, T. K., "Palynofacies, organic geochemical analyses and hydrocarbon potential of some Upper Jurassic-Lower Cretaceous rocks, the Sabatayn-1 well, Central Yemen". Arabian Journal of Geoscience, DOI 10.1007/s12517-013-0961-y. (2013).

[10] Al-Hakari, S. H. S., "Geometric Analysis and Structural Evolution of NW Sulaimani Area, Kurdistan Region, Iraq". Ph.D. dissertation, University of Sulaimani, Kurdistan Region, Iraq. pp. 309. (2011).

[11] Al-Qayim, B., Hussein, Sh., Qader. F. M., Al-Hakari, Shukor, B., Sardar, Z., Ahmed, D., Abdullah, H., "Integrated stratigraphic study of the Cretaceous petroleum-potential succession, Sulaimani area, Kurdistan, Iraq". Journal of Zankoy Sulaimani, special issue, Geokurdistan, pp.391-418. (2016).

[12] American Standard for Testing and Materials (ASTM), "Standard Test Method for Microscopical Determination of the Reflectance of Vitrinite Dispersed in Sedimentary Rocks". pp. 10. D7708, (2014).

[13] Aqrawi, A. A. M., Horbury, A. D., Goff, J. C., and Sadooni, F. N., "The Petroleum Geology of Iraq". Beaconsfield, Bucks, UK: Scientific Press Ltd, pp. 424. (2010).

[14] Basher, W, Ph., and Al-Samarraie, B., "Petrographic study of the Sarmord Formation in North Zakho area, Nw Iraq". Iraqi Bulletin of geology and Mining, Vol. 8, No. 2, pp. 45-63. (2012).

[15] Bellen, R. C. van, Dunnington, H.V., Wetzel, R., and Morton, D.M., "Lexique Stratigraphique International". Paris, Iraq: Fascicule 10 a, pp. 333. (1959).

[16] Buday, T., The Regional Geology of Iraq. Stratigraphy and Paleogeography (Vol. 1)". Mosul, Iraq: Dar Al-Kutib Publishing house, University of Mosul, pp. 445. (1980).

[17] Dembicki, H., "Three common source rock evaluation errors made by geologists during prospect or play appraisals". AAPG Bulletin, Vol. 93, No. 3, pp. 341-356. (2009).

[18] Dunnington, H.V., "Generation, Migration, Accumulation, and Dissipation of oil in Northern Iraq. Habitat of oil, a symposium". AAPG, Tulsa, G.L.Wecks (Ed.), pp.1194-1251. (1958).

[19] Edilbi, A.N., Mohammed, K.F., Sadeq, Z.H., Aldalawy, A.A., Zebari, B.G., Pirouei, M., Suramairy, R. and Ali, J.A., "Source rock potential and reservoir characterization of the Lower Cretaceous Sarmord Formation in selected sections in Kurdistan Region-Iraq". Arabian Journal of Geosciences, Vol. 12, No. 21, pp.647-664. (2019).

[20] English, J.M., Lunn, G.A., Ferreira, L., and Yacu, G., "Geologic Evolution of the Iraqi Zagros, and Its Influence on the Distribution of Hydrocarbons in the Kurdistan Region". AAPG Bulletin, Vol. 99, No. 2, pp. 231–272. (2015).

[21] Espitalié, J., "Use of Tmax as a maturation index for different types of organic matter. Comparison with Vitrinite Reflectance in: Burrus", (ed)I., Thermal Modeling in Sedimentary Basin, Edition Technip, Paris, pp. 475-496. (1986).

[22] Fatah, S. S., "Source Rock evaluation and Biomarker distribution of Middle Jurassic Sargelu Formation, Sulaimani area, Kurdistan region NE-Iraq". MSc thesis, University of Sulaimani, Unpublished, pp. 116. (2014).

[23] Ganz, H., and Kalkruth, W., "Application of infrared spectroscopy to the classification of kerogen-types and the evaluation of source rock and oil shale potentials". Fuel, Vol. 66, No. 5, pp. 708-711. (1987).

[24] Ganz, H., Kalkreuth, W., Oner, F., Pearson, M. J., Small, J. S., "Enhanced geochemical screening analysis- accurate determination of petroleum source – rock characteristics and comparision with standard techniques". Petroleum Geology of North West Europe, pp. 847-851. (1987).

[25] "Heritage report", Project Ref: ECV1851, pp.112. (2012).

[26] Hunt, J. M., "Petroleum Geochemistry and Geology", (2nd ed.), New York: W.H. Freeman and Company, pp. 743. (1996).

[27] International Committee for Coal Petrology (ICCP) "The new vitrinite classification (ICCP System 1994)".  Fuel, Vol. 77, pp. 349–358. (1998).

[28] International Committee for Coal Petrology (ICCP) "The new inertinite classification (ICCP System 1994)". Fuel, Vol. 80, pp. 459–471. (2001).

[29] International Organization for Standardization (ISO) 7404-2, "Methods for the Petrographic Analysis of Bituminous Coal and Anthracite — Part 2: Method for Preparing Coal Sample".  Geneva, Switzerland. pp. 8. (2014).

[30] Jacob H., "Classification, structure, genesis and practical importance of natural solid oil bitumen ("migrabitumen")". Int. J. Coal Geol. Vol. 11, pp. 65-79. (1989).

[31] Jassim, S. Z., and Buday, T., "Chapter 6: Units of the Unstable Shelf and the Zagros Suture", in Jassim, S. Z. and Goff, J. C. (ed.), Geology of Iraq, Brno, Czech Republic: Dolin, Prague and Moravian Museum. pp. 15-34. (2006).

[32] Jassim, S. Z., and Goff, J. C., "Chapter 3: Phanerozoic development of the Northern Arabian Plate", in Jassim, S. Z. and Goff, J. C. (ed.), Geology of Iraq, Brno, Czech Republic: Dolin, Prague and Moravian Museum. pp. 71-83. (2006).

[33] Karim, K.H., Salih, A. O., Ahmed, S. H., "Stratigraphic Analysis of Azmir-Goizha anticline by Nannofossils". Journal of Zankoy Sulaimani-Part A, Vol. 15, No. 2. pp. 103-124. (2013).

[34] Kubli, T. E., "Deformation History and Thin-skinned vs. Thick-skinned Tectonics in the Zagros Fold and Thrust Belt of Southeastern Kurdistan", Hydrocarbon Exploration in the Zagros Mountains of Iraqi Kurdistan and Iran, Geological Society Conference, Burlington House, Piccadilly. (2013).

[35] Peters, K. E., "Guidelines for Evaluating Petroleum Source Rock Using Programmed Pyrolysis", AAPG Bulletin, Vol. 70, No. 3, pp. 318-329. (1986).

[36] Peters, K., E., and Cassa, M., R., "Chapter 5: Applied Source Rock Geochemistry", in the petroleum system- from source to trap, edited by Magoon, L. B., and Dow, W. G., AAPG memoir 60, pp. 93-120. (1994).

[37] Peters, K.E., Walters, C.C. and Moldowan, J.M., "The biomarker Guide", (2nded.), Volumes 1&2, United Kingdom, Cambridge University Press, pp. 1155. (2005).

[38] Pickel, W., Kus, J., Flores, D., Kalaitzidis, S., Christanis, K., Cardott, B. J., Misz-Kennan, M., Rodrigues, S., Hentschel, A., Hamor-Vido, M., Crosdale, P. & ICCP "Classification of liptinite – ICCP System 1994".  International Journal of Coal Geology, Vol. 169, pp. 40-61. (2017).

[39] Sýkorová, I., Pickel, W., Christanis, K., Wolf, M., Taylor, G.H. and Flores, D. "Classification of huminite – ICCP System 1994". International Journal of Coal Geology Vol. 62, pp. 85-106. (2005).

[40] Thompson, C.L., and Dembicki, H., "Optical characteristics of amorphous kerogens and the hydrocarbon-generating potential of source rocks".  International Journal of Coal Geology, Vol. 6, pp. 229-249. (1986). 

[41] Tissot, B.P., and Welte, D.H., "Petroleum Formation and Occurrence. A new approach to Oil and Gas exploration", Berlin Heidelberg New York: Springer-Verlag, pp. 538. (1978).

[42] Tissot, B.P., and Welte D.H., "Petroleum formation and occurrence, 2nd revised and enlarged edition", Berlin Heidelberg New York: Springer-Verlag, pp. 699. (1984).

[43]"WesternZagros Map", Kurdistan & Northern Iraq Operator Activity Map. (2013).

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