Sequence stratigraphic framework and sedimentary evolution of the Cretaceous in southern Iraq

doi:10.13745/j.esf.sf.2022.2.61

Abstract

Abstract:

The Cretaceous is an important exploration and development target in southern Iraq. However, a lack of systematic sequence stratigraphic study among major oilfields has greatly restricted fine planning for the oilfield development and production. Therefore, it has great theoretical and practical significance to investigate the sequence stratigraphy and sedimentary systems in the study area. Here, guided by sequence stratigraphy and sedimentology theory, and based on the core data, mud logs, well logs and seismic data, the sequence boundaries are identified and sequences are delineated; meanwhile the evolutionary characteristics of the sedimentary system are analyzed. According to the results, the Cretaceous in southern Iraq is mainly composed of skeletal limestone, and the sequence interface types include unconformity, exposed surface, lithology abrupt surface and sedimentary facies transition surface types. The Cretaceous is divided into 2 first-level sequences (AP8, AP9), 6 second-level sequences (SS1-SS6) and 22 third-level sequences (SQ1-SQ22); the duration of each 3^rd sequence varies from 2-4 Ma. In the Lower Cretaceous, SS1 develops, from south to north, ramp-to-basin sedimentary system, and sediments evolve upward from basinal mudstone to inner ramp grainstone; sediments of the lower SS2 gradually evolve, SW-NE, from delta sandstone to deep-water shelf carbonates, while sediments of the upper part evolve from basinal mudstone to shallow-water shelf carbonates; and in SS3, sediments of the lower part evolve, SW-NE, from braided river coarse sandstone to shallow sea fine sandstone, while marine carbonate rock develops in the upper part. In the Upper Cretaceous, SS4 develops, from west to east, upward shallowing depositional successions of deep shelf-shallow water carbonate ramp-platform sedimentary systems; while fine-grained carbonate ramp sedimentary system, dominated by planktonic foraminifera limestone, develops in SS5; and in SS6, shallowing upward carbonate ramp sedimentary system develops in three stages, and shelf dolomite develops on the uppermost part. Carbonate ramp shoals, platform marginal shoals and two-stage sandstone deposits are the most favorable exploration and development targets in this area. The tectonic movement plays an important role in controlling the development and distribution of the inner ramps and marginal reefs and shoals.

Key words: Cretaceous, Iraq, sequence stratigraphy, sedimentary evolution, skeletal limestone

CLC Number:

HAN Haiying, GUO Rui, WANG Jun, QIN Guosheng, SUN Xiaowei, YU Yichang, SU Haiyang, GAO Yang. Sequence stratigraphic framework and sedimentary evolution of the Cretaceous in southern Iraq[J]. Earth Science Frontiers, 2023, 30(2): 122-138.

Figures/Tables 13

Fig.1 Sequence stratigraphy diagram for the Cretaceous strata of Iraq, Saudi Arabia, Qatar and Kuwait. Modified after [1].

Fig.2 Structural units of Iraq and location of the study area

Fig.3 Structural cross section of the Mesopotamia Basin in the Late Cretaceous. Modified after [19].

Fig.4 Seismic profile of the Cretaceous strata in the HF oilfield and sequence features of a typical core (core H316)

Fig.5 Sequence stratigraphic column of well HF-2 in the HF oilfield, southern Iraq

Fig.6 Sequence stratigraphy of the Cretaceous Sulaiy-Shuaiba Formations in southern Iraq (AB cross section location see Fig.2)

Fig.7 Ramp depositional facies distribution in the Yamama Formation, southern Iraq. Modified after [6].

Fig.8 Sequence stratigraphy of the Cretaceous Nahr Umr-Shuaiba Formations in southern Iraq (AB cross section location see Fig.2)

Fig.9 Sedimentary facies distribution in the Mishrif Formation in southern Iraq and location (red line) of the cross section in Fig.10. Modified after [68].

Fig.10 Schematic cross section showing the sedimentary facies of the Ahmadi-Mishrif Formations, southern Iraq

Fig.11 Sequence stratigraphy of the Cretaceous Khasib-Sadi Formations in southern Iraq (AC cross section location see Fig.2)

Fig.12 Sequence stratigraphy of the Cretaceous Hartha-Tayarat Formations in southern Iraq (AC cross section location see Fig.2)

Table 1 Sequence stratigraphic and distribution characteristic of Cretaceous in southern Iraq

References 29

[30]	AL-AMERI T K, AL-KHAFAJI A J, ZUMBERGE J. Petroleum system analysis of the Mishrif reservoir in the Ratawi, Zubair, North and South Rumaila oil fields, southern Iraq[J]. GeoArabia, 2009, 14(4): 91-108. DOI URL
[31]	IDAN R M, FAISAL R F. Application of geophysical logs to estimate the source rock quantity of Ratawi Formation, southern Iraq: a comparison study[J]. IOP Conference Series: Materials Science and Engineering, 2019, 579(1): 012025. DOI URL
[32]	AL-OBAIDI R Y, AL-AMERI T K, AL-KHAFAJI A J. Palynofacies, palaeoenvironment, and source rocks evaluation of Ratawi Formation, southern Iraq[J]. Arabian Journal of Geosciences, 2013, 6(9): 3303-3312. DOI URL
[33]	ARASU R T, NATH P K, KHAN B, et al. Stratigraphic features within the Ratawi shale member of the Lower Cretaceous Ratawi Formation and their hydrocarbon prospectivity in Sudaira-Abdali area, North Kuwait[C]// STEEPLES D. SEG Technical Program Expanded Abstracts 2012. Las Vegas: Society of Exploration Geophysicists, 2012: 1-5.
[34]	AL-TENDAIL S B, TAAL A, AL-ADWANI T, et al. Reviving a classic exploration play in Kuwait: the Lower Cretaceous Ratawi Formation[C]// Search and discovery article.AAPG Annual Convention and Exhibition 2012. Long Beach: AAPG, 2012: 1-36.
[35]	TANOLI S K, AL-AJMI M D, BEHBEHANI S M, et al. Sequence stratigraphic analysis of the Ratawi shale formation: implications for reservoir distribution and exploration potential in Kuwait[J]. GeoArabia, 2011, 16(1): 151-203. DOI URL
[36]	AL-MAFRAJI T G Z, AL-ZAIDY A A H. Microfacies architecture and stratigraphic development of the Yamama Formation, southern Iraq[J]. Iraqi Journal of Science, 2019, 60(5): 1115-1128. DOI URL
[37]	KHAIWKA M H. Order and repetitive nature of the Zubair deltaic facies, central and southern Iraq and northern Kuwait[J]. Marine and Petroleum Geology, 1990, 7(1): 38-43. DOI URL
[38]	AL-AMERI T K, PITMAN J, NASER M E, et al. Programed oil generation of the Zubair Formation, southern Iraq oil fields: results from Petromod software modeling and geochemical analysis[J]. Arabian Journal of Geosciences, 2011, 4(7/8): 1239-1259. DOI URL
[39]	DAVIES R B, CASEY D M, HORBURY A D, et al. Early to mid-Cretaceous mixed carbonate-clastic shelfal systems: examples, issues and models from the Arabian Plate[J]. GeoArabia, 2002, 7(3): 541-598. DOI URL
[40]	BOWMAN M W A, KOSTIC B, CAMPION N, et al. Lower Cretaceous deltaic deposits of the main pay reservoir, Zubair Formation, southeast Iraq: depositional controls on reservoir performance[M]//ALANZI H R, RAHMANI R A, STEEL R J, et al. Siliciclastic reservoirs of the Arabian plate. Tulsa:AAPG; Dhahran: Saudi Aramco, 2019: 219-260.
[41]	AL-SHAWI Z A A, MAHDI M M, MOHAMMED A H. New records of planktonic foraminifera in the Shuaiba Formation (Aptian Age), Mesopotamian plain, south of Iraq[J]. Iraqi Journal of Science, 2019, 60(6): 1322-1335.
[42]	AL-RUBAYE H H, GAYARA A D, AL-ZAIDY A A. Facies analysis and stratigraphic development of the Zubair Formation in the Mesopotamian zone, southern Iraq[J]. Iraqi Journal of Science, 2019, 60(2): 290-307.
[43]	AL-JAFAR M K, AL-JABERI M H. Well logging and electrofacies of Zubair Formation for upper sandstone member in Zubair oil field, Southern Iraq[J]. Iraqi Geological Journal, 2019, 52(1): 101-124.
[44]	ALI A J, NASSER M E. Facies analysis of the Lower Cretaceous oil-bearing Zubair Formation in southern Iraq[J]. Modern Geology, 1989, 13(3/4): 225-242.
[45]	AL-AMERI T K, BATTEN D J. Palynomorph and palynofacies indications of age, depositional environments and source potential for hydrocarbons: Lower Cretaceous Zubair Formation, southern Iraq[J]. Cretaceous Research, 1997, 18(6): 789-797. DOI URL
[46]	MOHAMMED K S, AL-ZAIDY A A. Facies analysis and sequence stratigraphy of the Barremian succession in the Luhais and Rachi oil fields, southern of Iraq[J]. Journal of University of Babylon for Engineering Sciences, 2018, 26(7): 340-361. DOI URL
[47]	AIAD A H, AL-ZAIDY Z A. Facies analyses and diagenetic features development of Albian-Aptian succession in the West Qurna oil field, southern Iraq[J]. Iraqi Journal of Science, 2018, 55(44): 2887-2901.
[48]	SAYYAB A S, MOHAMMED M U. The age of the Mauddud Formation at South Iraq[J]. Iraqi Journal of Science, 1984, 25(1/2): 47-55.
[49]	NASSER R H, NASSER M E. Microfacies evaluation of Mauddud Formation in Ratawi field, South Iraq[J]. Iraqi Journal of Science, 2017, 58(4A): 1818-1932.
[50]	吕洲, 王玉普, 王友净, 等. 伊拉克哈法亚油田白垩系Nahr Umr组砂岩储层物性控制因素[J]. 地球科学与环境学报, 2019, 41(6): 707-720.
[51]	NOORI N A, AL-SHEIKHLY S S J, AL-DULAIM S I M. Biostratigraphy of Mauddud Formation in Badra well-1, eastern Iraq[J]. Journal of Babylon University, 2016, 24(3): 740-754.
[52]	AL-DABBAS M A, JASSIM J A, QARADAGHI A I. Sedimentological and depositional environment studies of the Mauddud Formation, central and southern Iraq[J]. Arabian Journal of Geosciences, 2012, 5(2): 297-312. DOI URL
[53]	AL-MUSAWI F A, IDAN R M, SALIH A L M. Reservoir properties and facies distribution of Mishrif Formation in Ratawi oilfield, southern Iraq[M]//The structural geology contribution to the Africa-Eurasia geology:basement and reservoir structure, ore mineralisation and tectonic modelling. Cham: Springer International Publishing, 2018: 121-126.
[54]	MAHDI T A, AQRAWI A A M. Role of facies diversity and cyclicity on the reservoir quality of the mid-Cretaceous Mishrif Formation in the southern Mesopotamian Basin, Iraq[J]. Geological Society, London, Special Publications, 2017, 435(1): 85-105. DOI URL
[55]	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[J]. Modeling Earth Systems and Environment, 2018, 4(4): 1449-1465. DOI URL
[56]	NASSER M E. Microfacies analysis and stratigraphic development of the Mishrif Formation in the eastern of the Mesopotamian zone, southeastern Iraq[J]. Iraqi Journal of Science, 2018, 59(4B): 2053-2064.
[57]	李峰峰, 郭睿, 余义常, 等. 伊拉克M油田白垩系Mishrif组沉积特征及控储机理[J]. 沉积学报, 2020, 38(5): 1076-1087.
[58]	邓亚, 郭睿, 田中元, 等. 碳酸盐岩储集层隔夹层地质特征及成因: 以伊拉克西古尔纳油田白垩系Mishrif组为例[J]. 石油勘探与开发, 2016, 43(1): 136-144.
[1]	SADOONI F N, AQRAWI A A M. Cretaceous sequence stratigraphy and petroleum potential of the Mesopotamian Basin, Iraq[M]//ALSHARHAN A S, SCOTT R W. Middle East models of Jurassic/Cretaceous carbonate systems. Tulsa: SEPM Society for Sedimentary Geology, 2000: 315-334.
[2]	OWEN R M S, NASR S N. The stratigraphy of Kuwait-Basra area[C]// WEEKS L G. Habitat of oil. Tulsa: AAPG, 1958: 1252-1278.
[3]	METWALLI M H, PHILIP G, MOUSSLY M M. Petroleum-bearing formations in northeastern Syria and northern Iraq[J]. AAPG Bulletin, 1974, 58(9): 1781-1796.
[4]	IBRAHIM M W. Lithostratigraphy and subsurface geology of the Albian rocks of South Iraq[J]. Journal of Petroleum Geology, 1981, 4(2): 147-162. DOI URL
[5]	DUNNINGTON, H V. Stratigraphical distribution of oilfields in the Iraq-Iran-Arabia Basin[J]. Journal of the Institute of Petroleum, 1967, 5: 129-161.
[6]	SADOONI F N. Stratigraphic Sequence, microfacies, and petroleum prospects of the Yamama Formation, Lower Cretaceous, southern Iraq[J]. AAPG Bulletin, 1993, 77(11): 1971-1988.
[7]	IBRAHIM M W. Petroleum geology of Southern Iraq[J]. AAPG Bulletin, 1983, 67(1): 97-130.
[8]	AQRAWI A A M. Carbonate-siliciclastic sediments of the Upper Cretaceous (Khasib, Tanuma and Sa’di formations) of the Mesopotamian Basin[J]. Marine and Petroleum Geology, 1996, 13(7): 781-790. DOI URL
[9]	AQRAWI A A M, THEHNI G A, SHERWANI G H, et al. Mid-Cretaceous rudist-bearing carbonates of the Mishrif Formation: an important reservoir sequence in the Mesopotamian Basin, Iraq[J]. Journal of Petroleum Geology, 1998, 21(1): 57-82. DOI URL
[10]	JASSIM S Z, GOFF J C. Geology of Iraq[M]. Brno: Dolin, Prague and Moravian Museum, 1996: 131-150.
[59]	SANG H, LIN C S, JIANG Y M. Sequence stratigraphy and sedimentary study on Mishrif Formation of Fauqi oilfield of Missan in south east Iraq[J]. IOP Conference Series: Earth and Environmental Science, 2017, 64: 012042. DOI URL
[60]	王君, 郭睿, 赵丽敏, 等. 颗粒滩储集层地质特征及主控因素: 以伊拉克哈法亚油田白垩系Mishrif组为例[J]. 石油勘探与开发, 2016, 43(3): 367-377.
[61]	陈培元, 段晓梦, 郭丽娜, 等. 伊拉克米桑油田群中白垩统Mishrif组岩溶特征及作用模式[J]. 中国海上油气, 2017, 29(2): 46-52.
[62]	张义楷, 王志松, 史长林, 等. 伊拉克米桑油田碳酸盐岩储层成岩作用[J]. 科学技术与工程, 2016, 16(5): 45-53.
[63]	余义常, 孙龙德, 宋新民, 等. 厚壳蛤滩沉积成岩特征及对储集层的控制作用: 以伊拉克H油田白垩系Mishrif组为例[J]. 石油勘探与开发, 2018, 45(6): 1007-1019.
[64]	ZHONG Y, ZHOU L, TAN X C, et al. Characteristics of depositional environment and evolution of Upper Cretaceous Mishrif Formation, Halfaya oil field, Iraq based on sedimentary microfacies analysis[J]. Journal of African Earth Sciences, 2018, 140: 151-168. DOI URL
[65]	赵丽敏, 周文, 钟原, 等. 伊拉克H油田Mishrif组储集层含油性差异主控因素分析[J]. 石油勘探与开发, 2019, 46(2): 302-311.
[66]	CANTRELL D L, SHAH R A, OU J, et al. Depositional and diagenetic controls on reservoir quality: example from the Upper Cretaceous Mishrif Formation of Iraq[J]. Marine and Petroleum Geology, 2020, 118: 1-34.
[67]	李峰峰, 宋新民, 郭睿, 等. 厚层生物碎屑灰岩油藏隔夹层特征及成因:以中东地区M油田白垩系Mishrif组为例[J]. 石油学报, 2021, 42(7): 853-864. DOI
[68]	MAHDI T A, AQRAWI A A M, HORBURY A D, et al. Sedimentological characterization of the mid-Cretaceous Mishrif reservoir in southern Mesopotamian Basin, Iraq[J]. GeoArabia, 2013, 18(1): 139-174. DOI URL
[11]	SHARLAND P, ARCHER R, CASEY D, et al. Araian plate sequence stratigraphy[M]// GeoArabia Special Publication 2. Bahra in: Gulf Petrolink, 2001: 230-285.
[12]	SADOONI F N. The nature and origin of Upper Cretaceous basin-margin rudist buildups of the Mesopotamian Basin, southern Iraq, with consideration of possible hydrocarbon stratigraphic entrapment[J]. Cretaceous Research, 2005, 26(2): 213-224. DOI URL
[13]	AL-DABBAS M, AL-JASSIM J, AL-JUMAILY S. Retraction Note to: depositional environments and porosity distribution in regressive limestone reservoirs of the Mishrif Formation, southern Iraq[J]. Arabian Journal of Geosciences, 2017, 10(9): 1. DOI URL
[14]	ASSADI A, HONARMAND J, MOALLEMI S A, et al. Depositional environments and sequence stratigraphy of the Sarvak Formation in an oil field in the Abadan Plain, SW Iran[J]. Facies, 2016, 62(4): 1-22. DOI URL
[15]	SADOONI F N, ALSHARHAN A S. Stratigraphy, microfacies, and petroleum potential of the Mauddud Formation (Albian-Cenomanian) in the Arabian Gulf Basin[J]. AAPG Bulletin, 2003, 87(10): 1653-1680. DOI URL
[16]	AL-DABBAS M A, AL-JASSIM J A, QARADAGHI A I. Siliciclastic deposit of the Nahr Umr Formation, sedimentological and depositional environment studies, central and southern Iraq[J]. Arabian Journal of Geosciences, 2013, 6(12): 4771-4783. DOI URL
[17]	FOUAD S F A. Tectonic and structural evolution of the Mesopotamia Foredeep, Iraq[J]. Iraqi Bulletin of Geology and Mining, 2010, 6(2): 41-53.
[18]	李运振, 张鑫, 信石印, 等. 波斯湾盆地演化与超大型油气田形成[J]. 石油实验地质, 2019, 41(4): 548-559.
[19]	ZIEGLER M A. Late Permian to Holocene paleofacies evolution of the Arabian Plate and its hydrocarbon occurrences[J]. GeoArabia, 2001, 6(3): 445-504. DOI URL
[69]	MAHDI T A, AQRAWI A A M. Sequence stratigraphic analysis of the mid-Cretaceous Mishrif Formation, southern Mesopotamian Basin, Iraq[J]. Journal of Petroleum Geology, 2014, 37(3): 287-312. DOI URL
[70]	MOHAMMED A K A. Reservoir characteristics of Khasib Formation in Amara field, southern Iraq[J]. Iraqi Geological Journal, 2018, 51(2): 54-74.
[71]	HAN H, ZHAO L, XU X, et al. Characteristics and genesis of low to ultra-low permeability carbonate rocks: a case study in Late Cretaceous Sadi Formation in H oilfield, southeast of Iraq[C]. SPE reservoir characterization and simulation conference and exhibition. Abu Dhabi: Society of Petroleum Engineers, 2015.
[72]	GAYARA A D, MOUSA A K. Sequence stratigraphy and reservoir characterization of the Upper Campanian - Maastrichtian succession, Buzurgan field, southeastern Iraqi[J]. Iraqi Journal of Science, 2015, 56(2B): 1457-1464.
[73]	SADOONI F N. Stratigraphic and lithological characteristics of Upper Cretaceous carbonates in central Iraq[J]. Journal of Petroleum Geology, 1996, 19(3): 271-288. DOI URL
[74]	GAYARA A D, NASSER M E, KADHIM A J, et al. Paleoenvironments and sequence development of the Hartha Formation, southern Iraq[J]. International Journal of Advanced Research, 2016, 4(8): 1322-1333.
[75]	黄茜, 伏美燕, 赵丽敏, 等. 伊拉克HF油田上白垩统碳酸盐缓坡相储层发育特征[J]. 沉积学报, 2019, 37(2): 371-378.
[20]	贾小乐, 何登发, 童晓光, 等. 波斯湾盆地大气田的形成条件与分布规律[J]. 中国石油勘探, 2011, 16(3): 8-22,6.
[21]	冉怀江, 范乐元, 孔庆东, 等. 苏丹Muglad盆地中南部西斜坡沉积层序及有利地层圈闭预测[J]. 地学前缘, 2021, 28(1): 131-140. DOI
[22]	董艳蕾, 朱筱敏, 韦敏鹏, 等. 敦煌盆地五墩凹陷侏罗系层序地层格架与沉积体系分布[J]. 地学前缘, 2021, 28(1): 177-189. DOI
[23]	梅冥相. 层序地层学发展历程中的三个误判[J]. 地学前缘, 2014, 21(2): 67-80. DOI
[24]	康安, 梁力文, 周守信. 伊拉克米桑Buzurgan油田Mishrif组碳酸盐岩层序界面识别及层序划分[J]. 内蒙古石油化工, 2016, 42(10): 7-10.
[25]	ABEED Q, ALKHAFAJI A, LITTKE R. Source rock potential of the Upper Jurassic - Lower Cretaceous succession in the southern Mesopotamian Basin, southern Iraq[J]. Journal of Petroleum Geology, 2011, 34(2): 117-134. DOI URL
[26]	AL-AMERI T K, AL-MUSAWI F S, BATTEN D J. Palynofacies and source potential for hydrocarbon, uppermost Jurassic - basal Cretaceous in Sulaiy Formation, southern Iraq[J]. Cretaceous Research, 1999(20): 359-363.
[27]	AL-AMERI T K, AL-MUSAWI F A A. Hydrocarbon generation potential of the uppermost Jurassic - basal Cretaceous Sulaiy Formation, South Iraq[J]. Arabian Journal of Geosciences, 2011, 4(1/2): 53-58. DOI URL
[28]	SALEH A H. Microfacies and environmental study of the Lower Cretaceous Yamama Formation in Ratawi field[J]. Arabian Journal of Geosciences, 2014, 7(8): 3175-3190. DOI URL
[29]	何登发, 何金有, 文竹, 等. 伊拉克油气地质与勘探潜力[M]. 北京: 石油工业出版社, 2013:169-238.