Rock typing and petrophysical characterization play a vital role in constructing reservoir models for petroleum exploration and development. This study focuses on evaluating the petrophysical characteristics of the Late Cretaceous Abu Roash "G" Reservoirs at the East Alam El Shawish field in Egypt's Western Desert. The study involved five vertical wells and employed various techniques and analyses to investigate the reservoir. Lithology determination utilizing well logs and core analysis helps identify the lithology types and corresponding porosity of the Abu Roash "G" reservoirs. Sandstone and limestone lithologies with varying porosity ranges were identified, along with the influence of shale on neutron porosity values. Facies analysis of the Abu Roash "G" Member identified seven lithofacies types, categorized into shallow marine and deeper marine depositional environments. The petrophysical analysis involves evaluating gamma-ray logs, porosity, permeability, flow zone indicator (FZI), and reservoir quality index (RQI) values for each lithofacies type. This analysis classifies the core samples into seven reservoir rock types (RRT1 to RRT7) based on petrophysical attributes, providing a clear classification of the Abu Roash "G" reservoir interval. RRT1, RRT2, and RRT3 exhibit the highest reservoir quality, while RRT4 and RRT5 indicate moderate reservoir quality. RRT6 and RRT7 exhibit low reservoir quality due to unfavorable petrophysical behavior. The findings of this study provide valuable insights into the Abu Roash "G" reservoir, including its lithofacies, reservoir properties, and depositional environments. This knowledge is crucial for reservoir characterization and optimizing oil production strategies in the region.
Abdel-Fattah MI, Metwalli FI, Mesilhi ESI. Static reservoir modeling of the Bahariya reservoirs for the oilfields development in South Umbarka area, Western Desert, Egypt. J Afr Earth Sci. 2018; 138: 1-13. https://doi.org/10.1016/j.jafrearsci.2017.11.002
Abdelwahhab MA, Raef A. Integrated reservoir and basin modeling in understanding the petroleum system and evaluating prospects: The Cenomanian reservoir, Bahariya Formation, at Falak Field, Shushan Basin, Western Desert, Egypt. J Pet Sci Eng. 2020; 189: 107023. https://doi.org/10.1016/j.petrol.2020.107023
Abdelwahhab MA, Radwan AA, Mahmoud H, Mansour A. Geophysical 3D-static reservoir and basin modeling of a Jurassic estuarine system (JG-Oilfield, Abu Gharadig basin, Egypt). J Asian Earth Sci. 2022; 225: 105067. https://doi.org/10.1016/j.jseaes.2021.105067
Imam TS, Abdel-Fattah MI, Tsuji T, Hamdan HA. Mapping the geological structures in the Ras El Ush field (Gulf of Suez, Egypt), based on seismic interpretation and 3D modeling techniques. J Afr Earth Sci. 2022; 193: 104596. https://doi.org/10.1016/j.jafrearsci.2022.104596
Abdel-Fattah MI, Sen S, Abuzied SM, Abioui M, Radwan AE, Benssaou M. Facies analysis and petrophysical investigation of the Late Miocene Abu Madi sandstones gas reservoirs from offshore Baltim East field (Nile Delta, Egypt). Mar Pet Geol. 2022; 137: 105501. https://doi.org/10.1016/j.marpetgeo.2021.105501
Abdel-Fattah MI, Mahdi AQ, Theyab MA, Pigott JD, Abd-Allah ZM, Radwan AE. Lithofacies classification and sequence stratigraphic description as a guide for the prediction and distribution of carbonate reservoir quality: A case study of the Upper Cretaceous Khasib Formation (East Baghdad oilfield, central Iraq). J Pet Sci Eng. 2022; 209: 109835. https://doi.org/10.1016/j.petrol.2021.109835
Abdelmaksoud A, Amin AT, El-Habaak GH, Ewida HF. Facies and petrophysical modeling of the Upper Bahariya Member in Abu Gharadig oil and gas field, north Western Desert, Egypt. J Afr Earth Sci. 2019; 149: 503-16. https://doi.org/10.1016/j.jafrearsci.2018.09.011
Abuamarah BA, Nabawy BS, Shehata AM, Kassem OMK, Ghrefat H. Integrated geological and petrophysical characterization of oligocene deep marine unconventional poor to tight sandstone gas reservoir. Mar Pet Geol. 2019; 109: 868-85. https://doi.org/10.1016/j.marpetgeo.2019.06.037
Elhossainy MM, Abdelmaksoud A, Ali M, Alrefaee HA. Integrated sedimentological and petrophysical characterization of the Lower Cenomanian clastic Bahariya reservoir in Abu Gharadig Basin, Western Desert, Egypt. J Afr Earth Sci. 2021; 184: 104380. https://doi.org/10.1016/j.jafrearsci.2021.104380
Sarhan MA. Geophysical appraisal for the sandy levels within Abu Roash C and E members in Abu Gharadig Field, Western Desert, Egypt. J Pet Explor Prod Technol. 2021; 11: 1101-22. https://doi.org/10.1007/s13202-021-01107-3
Abdel-Fattah MI, Sarhan MA, Ali AS, Hamdan HA. Structural and petrophysical characteristics of the Turonian “AR/G″ reservoirs in heba field (Western Desert, Egypt): Integrated approach for hydrocarbon exploration and development. J Afr Earth Sci. 2023; 207: 105072. https://doi.org/10.1016/j.jafrearsci.2023.105072
Zhu S, Wang X, Qin Y, Jia Y, Zhu X, Zhang J, et al. Occurrence and origin of pore-lining chlorite and its effectiveness on preserving porosity in sandstone of the middle Yanchang Formation in the southwest Ordos Basin. Appl Clay Sci. 2017; 148: 25-38. https://doi.org/10.1016/j.clay.2017.08.005
Tobin RC, McClain T, Lieber RB, Ozkan A, Banfield LA, Marchand AME, et al. Reservoir quality modeling of tight-gas sands in Wamsutter field: Integration of diagenesis, petroleum systems, and production data. Am Assoc Pet Geol Bull. 2010; 94: 1229-66. https://doi.org/10.1306/04211009140
Worden RH, Armitage PJ, Butcher AR, Churchill JM, Csoma AE, Hollis C, et al. Petroleum reservoir quality prediction: overview and contrasting approaches from sandstone and carbonate communities. Geological Society, London: Special Publications; 2018; 435: 1-31. https://doi.org/10.1144/SP435.21
Shehata AA, Sarhan MA, Abdel-Fattah MI, Assal EM. Sequence stratigraphic controls on the gas-reservoirs distribution and characterization along the Messinian Abu Madi incision, Nile Delta Basin. Mar Pet Geol. 2023; 147: 105988. https://doi.org/10.1016/j.marpetgeo.2022.105988
Abdou A. Deep wells in Khalda West: A brief review. 14th EGPC Petroleum Conference, Cairo: 1998.
Amaefule JO, Altunbay M, Tiab D, Kersey DG, Keelan DK. Enhanced reservoir description: using core and log data to identify hydraulic (flow) units and predict permeability in uncored intervals/wells. Annual Technical Conference and Exhibition, Houston, Texas: OnePetro; October 3-6, 1993. https://doi.org/10.2118/26436-MS
Dolson JC, Shann M V, Matbouly SI, Hammouda H, Rashed RM. Egypt in the twenty-first century: petroleum potential in offshore trends. GeoArabia 2001; 6: 211-30. https://doi.org/10.2113/geoarabia0602211
Basheer AA, Metwalli FI, Amin AT, El-Dabaa SA. A new hydrocarbon prospect determination using the seismic interpretation and petrophysical evaluation of Bahariya reservoir in Nader field, north Western Desert, Egypt. J Afr Earth Sci. 2023; 200: 104891. https://doi.org/10.1016/j.jafrearsci.2023.104891
Wasfi SH. Biostratigraphic zonation of the Abu Roash formation in the western desert Egypt. 1973.
Tahoun SS, Deaf AS. Could the conventionally known Abu Roash “G” reservoir (upper Cenomanian) be a promising active hydrocarbon source in the extreme northwestern part of Egypt? Palynofacies, palaeoenvironmental, and organic geochemical answers. Mar Pet Geol. 2016; 76: 231-45. https://doi.org/10.1016/j.marpetgeo.2016.05.025
EGPC (Egyptian General Petroleum Corporation). Western desert, oil and Gas fields, a comprehensive overview. 11th Petroleum Exploration and Production Conference, Cairo: EGPC; 7-10 November 1992.
El Gezeery N, O’connor T. Cretaceous rock units of the western desert, Egypt. 13th Annual Meeting of Geological Society of Egypt, Cairo : Geological Society; 1975, p. 2.
Darwish M, Abdel Hamid M, Fahmy K. Geology and mode of hydrocarbon occurrence in the late cenomanian-early turonian, Abu Sannan area, western desert, Egypt. Earth Sci Ser. 1989; 3: 106-27.
Said R. The geology of Egypt. Rotterdam/Brookfield: AA Balkema;1962.
Fadul MF, El Dawi MG, Abdel-Fattah MI. Seismic interpretation and tectonic regime of Sudanese Rift System: Implications for hydrocarbon exploration in Neem field (Muglad Basin). J Pet Sci Eng. 2020; 191: 107223. https://doi.org/10.1016/j.petrol.2020.107223
Tammam M. Basin modeling of Qarun and west Qarun area and its implication on hydrocarbon generation, western desert, Egypt. Proceedings of the 13th of the Petroleum Conference of Egyptian General Petroleum Corporation, 1996, p. 433–46.
Hussein HM, Abd-Allah AM. Plate tectonics and geological evolution of Egypt. J Afr Earth Sci. 2001; 33: 475-96.
Bakry G, Eid A. Fault/seal paradox in the Abu Gharadig basin. 13th Petroleum Exploration and Production Conference, Cairo: EGPC; 1996, p. 81-96.
El Nady M, Hammad M. Evaluation of cretaceous hydrocarbon source rock in Badr El Din Concession, North Western Desert. J Environ Sci. 2000; 20: 25-51.
Selim ES, Sarhan MA. New stratigraphic hydrocarbon prospects for the subsurface Cretaceous: tertiary succession within Abu Gharadig Basin in the framework of sequence stratigraphic analyses, north Western Desert, Egypt. EuroMediterr J Environ Integr. 2023: 1–8. https://doi.org/10.1007/s41207-023-00403-0
Sarhan MA. Seismic delineation and well logging evaluation for albian Kharita Formation, South West Qarun (SWQ) field, Gindi Basin, Egypt. J Afr Earth Sci. 2019; 158: 103544. https://doi.org/10.1016/j.jafrearsci.2019.103544
Sarhan MA. Possibility of intrusive igneous body beneath the Cretaceous sequence in Abu Gharadig Basin, Egypt: Integration of geophysical data interpretations. Arab J Geosci. 2020; 13: Article number: 445. https://doi.org/10.1007/s12517-020-05436-1
Sharaf L, Ghanem M, Hussein S, El Nady M. Contribution to petroleum source rocks and thermal maturation of Jurassic-Cretaceous sequence, south Matruh, northern Western Desert, Egypt. Sedimentol Egypt. 1999; 7: 71-83.
Wong TF, Baud P. Mechanical compaction of porous sandstone. Oil Gas Sci Tech. 1999; 54: 715-27. https://doi.org/10.2516/ogst:1999061
Shehata AA, Sarhan MA. Seismic interpretation and hydrocarbon assessment of the post-rift Cenomanian Bahariya reservoir, Beni Suef Basin, Egypt. J Pet Explor Prod Technol. 2022; 12: 3243-61. https://doi.org/10.1007/s13202-022-01520-2
Moustafa AR, Saoudi A, Moubasher A, Ibrahim IM, Molokhia H, Schwartz B. Structural setting and tectonic evolution of the Bahariya Depression, Western Desert, Egypt. GeoArabia. 2003; 8: 91-124. https://doi.org/10.2113/geoarabia080191
Shehata AA, El Fawal FM, Ito M, Aboulmagd MA, Brooks HL. Senonian platform-to-slope evolution in the tectonically-influenced Syrian Arc sedimentary belt: Beni Suef Basin, Egypt. J Afr Earth Sci. 2020; 170: 103934. https://doi.org/10.1016/j.jafrearsci.2020.103934
Serra O. Fundamentals of well-log interpretation. New York: Elsevier; 1984.
Abdel-Fattah MI. Petrophysical characteristics of the messinian abu madi formation in the baltim east and north fields, offshore Nile delta, Egypt. J Pet Geol. 2014; 37: 183-95. https://doi.org/10.1111/jpg.12577
Poupon A, Leveaux J. Evaluation of water saturation in shaly formations. Log Anal. 1971; 12: 1-2.
Schlumberger. Log interpretation manual/applications. Vol. 2. Houston: Schlumberger Well Service, Inc.; 1974.
Burke JA, Schmidt AW, Campbell J, Raymond L. The litho-porosity cross plot: a method of determining rock characteristics for computation of log data. Log Anal. 1969; 10: 25-43.
Wilson MJ, Shaldybin MV, Wilson L. Clay mineralogy and unconventional hydrocarbon shale reservoirs in the USA. I. Occurrence and interpretation of mixed-layer R3 ordered illite/smectite. Earth Sci Rev. 2016; 158: 31-50. https://doi.org/10.1016/j.earscirev.2016.04.004
Riazi Z. Application of integrated rock typing and flow units identification methods for an Iranian carbonate reservoir. J Pet Sci Eng. 2018; 160: 483-97. https://doi.org/10.1016/j.petrol.2017.10.025
Shehata AA, Sarhan MA, Abdel-Fattah MI, Mansour S. Geophysical assessment for the oil potentiality of the Abu Roash “G” reservoir in West Beni Suef Basin, Western Desert, Egypt. J Afr Earth Sci. 2023; 199: 104845. https://doi.org/10.1016/j.jafrearsci.2023.104845
Sarhan MA, Ali AS, Abdel-Fattah MI. Geophysical assessment of basement rocks for use as an unconventional reservoir in the Rabeh East oil field, southern Gulf of Suez Basin. EuroMediterr J Environ Integr. 2023; 8: 409-23. https://doi.org/10.1007/s41207-023-00372-4
Worden RH, Morad S. Quartz cementation in oil field sandstones: a review of the key controversies. Quartz Cementation in Sandstones, Wiley; 2000, p. 1–20. https://doi.org/10.1002/9781444304237.ch1
Al-Ramadan K, Morad S, Proust JN, Al-Aasm I. Distribution of diagenetic alterations in siliciclastic shoreface deposits within a sequence stratigraphic framework: evidence from the Upper Jurassic, Boulonnais, NW France. J Sediment Res. 2005; 75: 943-59. https://doi.org/10.2110/jsr.2005.072
Palabiran M, Akbar MNA, Listyaningtyas SN. An analysis of rock typing methods in carbonate rocks for better carbonate reservoir characterization: A case study of Minahaki Carbonate Formation, Banggai Sula Basin, Central Sulawes. In 41th Scientific Annual Meeting of Indonesian Association of Geophysicists (Pit Hagi) Lampung, (Aip Conference Proceedings), 2016
Ewida HF, Sarhan MA. Efficiency of post-stack processing in enhancing seismic data quality: a case study of Southwest Qarun-Field, Gindi Basin, Egypt. EuroMediterr J Environ Integr. 2023: 1-9. https://doi.org/10.1007/s41207-023-00401-2
Zhang X, Lin C-M, Cai Y-F, Qu C-W, Chen Z-Y. Pore-lining chlorite cements in lacustrine-deltaic sandstones from the upper Triassic Yanchang formation, Ordos Basin, China. J Pet Geol. 2012; 35: 273-90. https://doi.org/10.1111/j.1747-5457.2012.00530.x
Zhang K, Guo Y, Bai G, Wang Z, Fan B, Wu J, et al. Pore-structure characterization of the Eocene Sha-3 sandstones in the Bohai Bay Basin, China. Energy & Fuels. J Pet Geol. 2012; 35: 1579-91. https://doi.org/10.1111/j.1747-5457.2012.00530.x
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