Skip to main content
Log in

Sedimentary units-layering system and depositional model of the carbonate Mishrif reservoir in Rumaila oilfield, Southern Iraq

  • Original Article
  • Published:
Modeling Earth Systems and Environment Aims and scope Submit manuscript


The Mishrif Formation (Cenomanian–Lower Campanian) is the main productive oilfield at Basrah in southern Iraq. It mainly comprises of shales and carbonates characterized by vertical phase transitions, including seals and oil reservoirs. This study establishes the Cenomanian–Campanian sequence stratigraphic framework through the integration of geochemical and geophysical data in order to distinguish between the stratigraphic intervals of shale and non-shale along oil wells in the Rumaila Oil Field that penetrates the Mishrif, Khasib and Tanuma formations. The geochemical profile has shown that carbonate and shale are the main lithologies along the 315 m stratigraphic interval from the top of Tanuma to the base of Mishrif, in the oil well WQ2-139. The stratigraphic column accordingly was divided into twenty stratigraphic intervals (zones); four zones in Tanuma, five zones in Khasib and eleven zones in the Mishrif Formation. The lower part of the Mishrif Formation is the main reservoir in the stratigraphic column as already known, yet the problem lies in the controversy over the number of productive units and their stratigraphic intervals. The porosity, lithology and fluid characters were discriminated based on distribution temperature (DT), Distribution Temperature Sensing (DTS) and RHOB logs as well as the compressional-wave velocity (Vp), shear-wave velocity (Vs) and density logs. The shale, gas limestone, oil limestone and brine limestone are well estimated and presented where the chi angle is about 0° and fluid-fill (i.e. oil from brine) is 30°–50°. This study provided headway in establishing milestones in the stratigraphic framework that have an important effect in determining reservoir storage quality.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or Ebook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11

Similar content being viewed by others


  • Aigner T, Schauer M, Junghans WD, Reinhardt L (1995) Outcrop gamma-ray logging and its applications: examples from the German Triassic. J Sediment Geol 100:47–61

    Article  Google Scholar 

  • Aisharhan AS, Kendall CG (1991) Cretaceous chronostratigraphy, unconformities and eustatic sea-level changes in the sediments of Abu Dhabi, United Arab Emirates. Cretac Res 12:379–401

    Article  Google Scholar 

  • Aksoy A, Nagadi MM (2006) Total and spectral natural gamma-ray logs of core samples. Arab J Sci Eng 31(1A):1–22

    Google Scholar 

  • Al-Bahadily JK, Nasser ME (2017) Petrophysical properties and reservoir modeling of Mishrif formation at Amara oil field, Southeast Iraq. Iraq J Sci 58(3A):1262–1272

    Google Scholar 

  • Alkersan HF (1975) Depositional environments and geologic history of the Mishrif formation in southern Iraq: 9th Arab Petroleum Congress. In: Dubai, United Arab Emirates, paper, 121:1–18

  • Al-Khayat A (1998) Evaluation study of Mishrif Formations in West-Qurna oil field. OEC Unpublished Report

  • Alsharhan AS, Nairn AE (1988) A review of the Cretaceous formations in the Arabian Peninsula and Gulf—Part II. Mid-Cretaceous (Wasia Group) stratigraphy and paleogeography. J Petrol Geol 11:89–112

    Article  Google Scholar 

  • Al-Siddiki A (1975) Regional geology of south Iraq. South Oil Company (SOC) unpublished report. Basra, Iraq

    Google Scholar 

  • Aqrawi AA (1996) Carbonate-siliciclastic sediments of the upper cretaceous (Khasib, Tanuma and Sa’di Formations) of the Mesopotamian Basin. J Mar Petrol Geol 7:781–790

    Article  Google Scholar 

  • Aqrawi AA, Thehni GA, Sherwani AD, Kareem BM (1998) Mid cretaceous rudist-bearing carbonates of the Mishrif formation: an important reservoir sequence in the Mesopotamian Basin. J Petrol Geol 21:57–82

    Article  Google Scholar 

  • Armstrong-Altrin J, Lee Y, Surendra V, Ramasamy S (2004) Geochemistry of sandstones from the Upper Miocene Kudankulam Formation, Southern India: implications for provenance, weathering, and tectonic setting. J Sediment Res 74:285–297

    Article  Google Scholar 

  • Awadh SM (2018) Physico-chemical characterization and salinity distribution of the oilfield water in the Upper Member of Zubair sandstones in Rumaila North Oilfield, southern Iraq. Iran J Oil Gas Sci Technol 7(1):20–39

    Google Scholar 

  • Awadh SM, Al-Yaseri A, Hussein AR (2014) The influence of kaolinite and pH on permeability in the Zubair reservoir in the North Rumaila Oilfield, southern Iraq. Iraqi J Sci 55(2B):780–789

    Google Scholar 

  • Baumgardner Jr. RW, Hamlin HS, Rowe HD (2014) High-resolution core studies of Wolfcamp/ Leonard Basinal Facies, southern Midland Basin, Texas. Search and Discovery Article #10607 (2014) Adapted from poster presentation given at AAPG, Southwest Section Annual Convention, Midland, Texas

  • Buchette TP (1993) Mishrif formation (Cenomanian-Turonian), southern Arabian Gulf: carbonate platform growth along a cratonic basin margin. In: Simo JA, Scott RW, Masse J-P (eds) Cretaceous carbonate platforms. AAPG Memoir 56, pp 185–199

    Google Scholar 

  • Buday T (1980) The regional geology of Iraq. Dar Al-Kutub Publication House, Mosul, p 1

    Google Scholar 

  • Chamberlain AK (1984) Surface gamma-ray logs; a correlation tool for frontier areas. AAPG Bull 68:1040–1043

    Google Scholar 

  • Dunnington HV, Wetzel R, Morton DM (1959) Mesozoic and Paleozoic: In: van Bellen RC, Dunnington HV, Wetzel R, Morton DM (eds), Lexique Stratigraphique International III Asie, International geological congress commission on stratigraphy, Paris, p 333

  • Ferti WH, Frost Jr (1982) Experiences with natural gamma-ray spectra logging in North America. Soc Petrol Eng AIME 11145:1–24

    Google Scholar 

  • Gardner J, Lehmann Ch, Olatoke OJ (2015) An integrated surface description of the Rumaila field, southern Iraq (ISD4). The Mishrif formation, Sect. 1: Introduction, ISD, Iraqi technical services group. Doc version 1

  • Haq BU, Hardenbol J, Vail PR (1988) Mesozoic and Cenozoic chronostratigraphy and cycles of sealevel change. In: Wilgus KW, Posamentier H, Hastings BS, van Wagoner J, Ross CA, Kendall CGSC (eds), Sea-level changes: an integrated approach. SEPM Special Publication, 42:71–108

  • Harris PM, Frost SH (1984) Middle cretaceous carbonate reservoirs, Fahud field and northwestern Oman. AAPG Bull 68:649–658

    Google Scholar 

  • Hlelai MA, Khorshid SZ (2015) 3-D lithofacies model of Mishrif formation in Nasiriyah oil field Southwestern Iraq. Iraq J Sci 56(4C):3452–3462

    Google Scholar 

  • International Atomic Energy Agency (IAEA) (2003) Guidelines for radio element mapping using gamma ray spectrometry data

  • James GA, Wynd JG (1965) Stratigraphic nomendature of Iranian oil consortium agreement area. J AAPG Bull 49:2182–2245

    Google Scholar 

  • Koptíková LK, Bábek O, Hladil J, Kalvoda J, Slavík L (2010) Stratigraphic significance and resolution of spectral reflectance logs in lower Devonian carbonates of the Barrandian area, Czech Republic; a correlation withmagnetic susceptibility and gamma-ray logs. J Sediment Geol 225:83–98

    Article  Google Scholar 

  • Lüning S, Schulz F, Marzouk A-M, Kuss J, Gharaibeh A, Kolonic S (2004) Uranium-enriched horizons refine the stratigraphic framework of Cenomanian–Turnonian (Late Cretaceous) strata in central Jordan and northern Tunisia. Z Dtsch Geol Ges 155:49–60

    Google Scholar 

  • Murris RJ (1980) Middle east-stratigraphic evolution and oil habitat. J AAPG Bull 64:597–618

    Google Scholar 

  • Nazeera A, Abbasib SA, Solangi SH (2016) Sedimentary facies interpretation of gamma ray (GR) log as basic well logs in central and lower indus Basin of Pakistan. Geodes Geodyn 7(6):432–443

    Article  Google Scholar 

  • Olatoke OJ (2015) Mishrif seismic interpretation, presentation to the ROO. South Oil Company (SOC), Basrah

    Google Scholar 

  • Owen RM, Nasr SN (1958) Stratigraphy of the Kuwait Basrah area. In: Weeks LG (ed) Habitat of oil. AAPG, Tulsa, pp 1252–1278

    Google Scholar 

  • Pettijohn FJ (1975) Sedimentary rocks, 2nd edn. Harper and Row Publishers, New York, p 628

    Google Scholar 

  • Scott RW (1990) Chronostratigraphy of the Cretaceous carbonate shelf, southeastern Arabia. In: Robertson AHF (eds) Tectonics of the Oman Region: Geological Society of London Special Publication 49:89–108

  • Scott RW, Frost SH, Shaffer BI (1988) Early Cretaceous sea-level curves, Gulf Coast and southeastern Arabia. In: Wilgus KW, Posamentier H, Hastings BS, Wagoner Van J, Ross CA, Kendall CC (eds) Sea-level changes-an integrated approach, SEPM Special Publication, New York, 42: 275–284

    Chapter  Google Scholar 

  • Sherwani GH, Mohammad IQ (1993) Sedimentological factors controlling the depositional environment of Cenomanian Mishrif Formation, Southern Iraq. Iraq Geol J 26:122–134

    Google Scholar 

  • Siddiqui NA, El-Ghali MA, Mijinyawa A, Ben-Awuah J (2013) Depositional environment of shallow-marine sandstones from outcrop gamma-ray logs, Belait Formation, Meragang Beach, Brunei Darussalam. Res J Environ Earth Sci 5(6):305–324

    Google Scholar 

  • Simone S, Perrotta S, Sboix C, Periere M (2013) Sedimentology of the Mishrif formation (Cenomanian–Turonian) of the Rumaila field from historic core; Phases 1 and 2; final report. Con 990/P0031:1–618

    Google Scholar 

  • SOC - South Oil Company (2012) Overview of Mishrif geology. Unpublished report (Poster)

  • van Buchem FS, Razin P, Homewood PW, Philip JM, Eberli GP, Platel JP, Roger J, Eschard R, Guy MJ, Desaubliaux T, Leduc JP, Labourdette R, Cantaloube S (1996) High resolution sequence stratigraphy of the Natih formation (Cenomanian/Turonian) in Northern Oman: distribution of source rocks and reservoir facies. J GeoArabia 1(1):6591

    Google Scholar 

  • Veizer J, Demovic R (1974) Strontium as a tool in facies analysis. J Sediment Petrol 44:93–115

    Google Scholar 

  • Vincent B, Witkowski FJ, Crowley S(2012) Chemostratigraphy and diagenesis in the Mishrif Formation of the Rumaila Field, Reporet, Basra Iraq, 127

  • Yaalon DH (1961) Mineral composition of the average shale. Sediment Petrol 29:577–588

    Google Scholar 

Download references


The authors are very grateful to the Iraqi Ministry of Oil for agreeing to release the information, and our deep thanks to South Oil Company (SOC) for providing us with the core samples and information. Authors grateful to Dr. Rafid (Faculty of Pharmacy at the Basrah University) for conducting the SEM analysis.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Salih Muhammad Awadh.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Al-Mimar, H.S., Awadh, S.M., Al-Yaseri, A.A. et al. Sedimentary units-layering system and depositional model of the carbonate Mishrif reservoir in Rumaila oilfield, Southern Iraq. Model. Earth Syst. Environ. 4, 1449–1465 (2018).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: