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10 | Halliburton Landmark B Marcellus Average TOC Marcellus Maturity Windows NE Core NE Core SW Core SW Core A Exploration Insights | 11 Maturity Average TOC Main Gas Late Gas Supermature Maturity Figure 6> A) Cross-plot of first year initial production rate versus average total organic carbon (TOC) within the Marcellus play. Note that the Southwest Core generally has higher TOC than the Northeast Core. Production is sensitive to TOC, particularly within the Northeast Core. B) Cross-plot of first year initial production rate versus thermal maturity within the Marcellus play. Note that the production rate is generally low within the oil window, while the gas window contains the majority of the high performing wells. Production data courtesy of Rystad Energy ShaleWellCube. Based on the Marcellus analogue, well production within the Jurassic shale plays across the Middle East is likely to be sensitive to both TOC and thermal maturity. The primary area of shale play development, thus far, has been in the wet gas window in the Jafurah Basin, where the lateral target is the basal, high TOC unit within the Tuwaiq Mountain Formation (Hakami et al., 2016). Additionally, the area for potential development within the Diyab play in the United Arab Emirates is within the wet gas window; therefore, organic porosity is envisaged to be relatively high, provided the target horizons have high TOC. However, the Tuwaiq Mountain Formation in the Khaleej al-Bahrain sub-basin, offshore Bahrain, is within the oil window (Al Ansari et al., 2016). This might pose a potential challenge to the development of the play, particularly if unconventional reservoirs with lower porosity and permeability coincide with higher viscosity oils, which are likely to be more difficult to flow . CONCLUSIONS Analogues can accelerate understanding within the emerging Middle–Late Jurassic resource interval of the Middle East, and can inform exploration, appraisal, and development decisions. The Vaca Muerta (stratigraphic architecture), Austin Chalk (natural fractures), Eagle Ford (mineralogy), and Marcellus (porosity development) are recognized as analogues, which characterize different aspects of the resource interval. Although the Middle–Late Jurassic resource interval is widespread across the Middle East, geologically informed high-grading workflows are required to identify the areas that are truly prospective. This is achieved through a combination of unconventional screening, assessment of resource in-place, and the identification of geological sweet spots based on understanding gained from analogues. The REFERENCES Allix, P., A. Burnham, T. Fowler, M.H.R. Kleinberg and B. Symington 2010. Coaxing Oil from Shale. Oilfield Review, v. 22, no. 4, p. 4-16. (XURBB_491604). 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The Marcellus Shale Play: Its Discovery and Emergence as a Major Global Hydrocarbon Accumulation. In R.K. Merrill and C.A. Sternbach (Eds.), Giant fields of the decade 2000–2010. AAPG Memoir no. 113, p. 55-90. (XURBB_639304). » More Literature On This Article ACKNOWLEDGMENTS This article is adapted from a conference paper (19975-MS) presented at IPTC 2020. AUTHORS Alex Bromhead, Senior Geoscientist, Unconventionals, Halliburton Landmark Alex started his career with Neftex Petroleum Consultants in 2013. Since 2016, he has focused on unconventional play evaluation and led projects on the characterization, screening, and resource assessment of unconventional plays worldwide. Alex holds a M.Sci degree in Geology from the University of Southampton. David Weeks, Geoscientist, Neftex Business Development, Halliburton Landmark David is a petroleum geologist with eight years of experience working in the upstream sector of the petroleum industry. His career began in 2010, with a summer placement at BG Group. He went on to work at Neftex, spending much of his time on the consultancy team. He also has experience working in software research and development, and unconventional shale resource evaluation. David has a keen interest in economics and market trends, and completed an economics course at the Oxford University Department for Continuing Education in 2017. He holds a BSc degree in Geology from Southampton University. Dr. Owen E. Sutcliffe, Head of Global Geology and Geophysical Practices, Halliburton Landmark Owen started his career as a postdoctoral research assistant with the University of Wales, Aberystwyth and LASMO, researching the petroleum geology of the Late Ordovician glacial clastics of North Africa. In 2000, he joined Badley Ashton & Associates as a sedimentologist, before his employment began at Neftex Petroleum Consultants in 2003. Since the acquisition of Neftex by Halliburton in 2014, Owen has held roles as Head of Stratigraphy and as Manager of Neftex ® Insights. He is a member of The Geological Society, London and the PESGB. DISCLAIMER This article is a synthesis based upon published data and information, and derived knowledge created within Halliburton. Unless explicitly stated otherwise, no proprietary client data has been used in its preparation. If client data has been used, permission will have been obtained and is acknowledged. Reproduction of any copyrighted image is with the permission of the copyright holder and is acknowledged. The opinions found in the articles may not necessarily reflect the views and/or opinions of Halliburton Energy Services, Inc. and its affiliates including but not limited to Landmark Graphics Corporation.