A near-shore clastic-carbonate mixing mode in a continental rift basin (early Oligocene, eastern Shijiutuo Uplift, Bohai Bay Basin, China): sedimentology, reservoir characteristics and exploration practice
A comprehensive sedimentary and reservoir analysis was conducted based on seismic, well logging, core and relative test data, taking Members 1 and 2 of Shahejie Formation of the early Oligocene in the steep slope belt, eastern Shijiutuo Uplift (STU), Bohai Bay Basin (BBB) as a case. The study indicates that a near-shore mixed fan deposit formed in the study area and developed characteristics and pattern of a high-quality reservoir. The mixed clastic-carbonate rocks constitute Members 1 and 2 of Shahejie Formation which developed along the steep slope belt and is named as a near-shore mixed fan. The mixed fan of the study area is mainly composed of microfacies of proximal channel, mixed deposited channel, mixed clastic beach, mixed bioclastic (grain) beach, with vertical multi-stage superimposition feature, and basically a similar shape as modern near-shore fans. It constitutes a new depositional type developing in the steep slope belt of a characteristic and complex lacustrine rift basin in the study area. This mixed fan in the steep slope of eastern STU is controlled by comprehensive factors including tectonics, clastic material supply, climate, palaeogeomorphology and hydrodynamic conditions. The reservoir quality of Members 1 and 2 of Shahejie Formation of eastern STU is, however, actually controlled by the sedimentary environment and diagenesis processes. Coarse-grained mixed rocks of near-shore fans, rich in bioclastics, can form excellent reservoirs, characterized by resistance to compaction, easy to dissolution, little influenced by burial depth and high production of oil and gas, which enable them become key exploration targets of medium- deep strata of BBB. Analyses of high-quality reservoir, its controlling factors and the oil and gas exploration implications of the near-shore mixed fan developing in the study area give a deeper insight into discussions of the same type of mixed rocks of other lacustrine rift basins worldwide.
[1] Abdelkarim A.A., Abdullatif O.M., Babalola L.O., Makkawi M.H., Yassin M.A.2019. High-resolution lithofacies and porosity modeling of the mixed siliciclastic-carbonate deposits of the Burdigalian Dam Formation, Eastern Saudi, Arabia.International Journal of Earth Sciences 108:155-172. [2] Brooks G.R., Doyle L.J., Suthard B.C., Locker S.D., Hine A.C.2003. Facies architecture of the mixed carbonate/siliciclastic inner continental shelf of west-central Florida: implications for Holocene barrier development.Marine Geology 200: 325-349. [3] Bruckner W. D.1953. Cyclic calcareous sedimentation as an index of climatic variations in the past.Journal of Sedimentary Petrology 23(4): 235-237. [4] Button, A., Vos, R. G.1977. Subtidal and intertidal clastic and carbonate sedimentation in a macrotidal environment: an example from the lower Proterozoic of South Africa.Sedimentary Geology 18: 175-200. [5] Campbell, A E.2005. Shelf-geometry response to changes in relative sea level on a mixed carbonate-siliciclastic shelf in the Guyana Basin.Sedimentary Geology 175: 259-275. [6] Chiarella D., Longhitano S. G., Tropeano M.2017. Types of mixing and heterogeneities in siliciclastic-carbonate sediments.Marine and Petroleum Geology 88: 617-627. [7] Coffey, B.P., Read, J.F.2004. Mixed carbonate-siliciclastic sequence stratigraphy of a Paleogene transition zone continental shelf, southeastern USA.Sedimentary Geology 166: 21-57. [8] Dix, G. R, Parras, A.2014. Integrated diagenetic and sequence stratigraphy of a late Oligocene-early Miocene, mixed-sediment platform (Austral Basin, southern Patagonia): Resolving base-level and paleoceanographic changes, and paleoaquifer characteristics.Sedimentary Geology 307: 17-33. [9] Dong G.Y., Chen H.D., He Y.B.2007. Some Problems on the Study of the Mixed Siliciclastic-Carbonate Sediments.Advances in Earth Science 22(9): 931-939. (in Chinese with English abstract) [10] Dong Y.L.,, Zhu X.M., Hua S.J.2011. Genetic types and evolutionary model of mixed clastic-carbonate deposits in the lower part of the Sha-1 Formation,the Huanghua Depression.Oil & Gas Geology 32(1): 98-106. (in Chinese with English abstract) [11] Dorsey, R.J., Kidwell, S.M.1999. Mixed carbonate-siliciclastic sedimentation on a tectonically active margin: example from the Pliocene of Baja California Sur, Mexico.Geology 27: 935-938. [12] Feng J.L., Hu K., Cao J.2011. A review on mixed rocks of terrigenous clastics and carbonates and their petroleum-gas geological significance.Geological Journal of China Universities 17(2): 297-307. (in Chinese with English abstract) [13] García-Hidalgo J F., Gil J., Segura M., Dominguez C.2007. Internal anatomy of a mixed siliciclastic-carbonate platform: the Late Cenomanian - Mid Turonian at the southern margin of the Spanish Central System.Sedimentology 54(6): 1245-1271. [14] Glider, S.A., Leloup, P.H. Courtillot, V.1999. Tectonic evolution of Tancheng -Lujiang (Tan-Lu) fault via Middle Triassic to Early Cenozoic paleomagnetic.Journal of Geophysical Research 104(B7): 15365-15390. [15] Hsiao L.Y., Graham S.A., Tilander N.2004. Seismic reflection imaging of a major strike-slip fault zone in a rift system: Palaeogene structure and evolution of the Tan -Lu fault system, Liaodong Bay, Bohai, offshore China.AAPG Bulletin 88, 71-97. [16] Jiang, M.S., Sha, Q.A.1995. Research advances in the mixed siliciclastic-carbonate sedimentary systems.Advance in Earth sciences 10(6): 551-554. (in Chinese with English abstract) [17] John, C. M, Mutti, M., Adatte, T.2003. Mixed carbonate-siliciclastic record on the North African margin (Malta)-- coupling of weathering processes and mid Miocene climate.Geological Society of America Bulletin 115: 217-229. [18] Leila M., Moscariello A., Kora M., Mohamed A., Samankassou E.2020. Sedimentology and reservoir quality of a Messinian mixed siliciclastic-carbonate succession, onshore Nile Delta, Egypt.Marine and Petroleum Geology 112:104076. [19] Li X.H., Liu W.J., Zheng R.C.1997. Hybrid facies and mechanism of the formation of the mixed Devonian carbonate-siliciclastic sediments in the Longmen Mountain area, Sichuan.Sedimentary Facies and Palaeogeography 17(3): 1-9. (in Chinese with English abstract) [20] Liu H., Xia Q.L., Somerville I.D., Wang Y., Zhou X.H., Niu C.M., Du X.F., Zhang X.T.2015. Palaeogene of the Huanghekou Sag in the Bohai Bay Basin, NE China: deposition-erosion response to a slope break system of rift lacustrine basins.Geological Journal 50: 71-92. [21] Liu H., Meng J., Banerjee S.2017. Estimation of palaeo-slope and sediment volume of a lacustrine rift basin: a semi-quantitative study on the southern steep slope of the Shijiutuo Uplift, Bohai Offshore Basin, China.Journal of Asian Earth Sciences 147: 148-163. [22] Liu H., Xia Q. L., Zhou X.H.2018. Geologic-seismic models, prediction of shallow-water lacustrine delta sandbody and hydrocarbon potential in the Late Miocene, Huanghekou Sag, Bohai Bay Basin, northern China.Journal of Palaeogeography7(1): 66-87. [23] Liu H., van Loon A.J., Xu J., Tian L.X., Du X.F., Zhang X.T., Chen D.L.2020. Relationships between tectonic activity and sedimentary source-to-sink system parameters in a lacustrine rift basin: a quantitative case study of the Huanghekou Depression (Bohai Bay Basin, E China).Basin Research 32: 587-612. [24] Luo S.S., Liu K. Y., He Y.B.2004. Mixed sedimentary characteristics and mode of terrigenous clastics and carbonate in Es4 of Bonan Depression.Journal of Jianghan Petroleum Institute 26(4): 19-21. (in Chinese with English abstract) [25] Longhitano S.G., Sabato L., Tropeano M., Gallicchio S.2010. A mixed bioclastic-siliciclastic flood-tidal delta in a microtidal setting: depositional architectures and hierarchical internal organization (Pliocene, southern apennine, Italy). Journal of Sedimentary Research 80: 36-53. [26] Ma, Y.P., Liu, L.2003. Sedimentary and Diagenetic Characteristics of Paleogene Lacustrine “Hunji” Rock in Beach District, Dagang.Acta Sedimentologica Sinica 21(4): 607-613 (in Chinese with English abstract). [27] Man T.I.2014. Facies analysis and sequence stratigraphy of the Cenomanian-Turonian mixed siliciclastic-carbonate sediments in west Sinai, Egypt.Sedimentary Geology 307: 34-46. [28] Mata, S. A, Bottjer, D. J.2011. Origin of Lower Triassic microbialites in mixed carbonate-siliciclastic successions:Ichnology, applied stratigraphy, and the end-Permian mass extinction.Palaeogeography, Palaeoclimatology, Palaeoecology 300: 158-178. [29] Maxwell, W.G. H., Swinchatt, J. P.1970. Great Barrier reef: regional variation in a terrigenous-carbonate province.Geological Society of America Bulletin 81(3): 691-724. [30] Moissette P., Cornée J.J., Mannaï-Tayech B., Rabhi M., André J.P., Koskeridou E., Méon H.2010. The western edge of the Mediterranean Pelagian Platform: a Messinian mixed siliciclastic-carbonate ramp in northern Tunisia.Palaeogeography, PalaeoclimatolOgy, Palaeoecology 285: 85-103. [31] Monstad S.2000. Carbonate sedimentation on inactive fan-delta lobes: response to sea-level changes, Sant-Llorenc del Munt fan-delta complex, NE Spain.Sedimentary Geology 138: 99-124. [32] Morsilli M., Bosellini F.R., Pomar L., Hallock P., Aurell M., Papazzoni C.A.2012. Mesophotic coral buildups in a prodelta setting (Late Eocene, southern Pyrenees, Spain): a mixed carbonate-siliciclastic system.Sedimentology 59: 766-794. [33] Moscardelli L., Ochoa, J ,. Lunt, I., Zahm L.2019. Mixedsiliciclastic-carbonate systems and their impact for the development of deep-water turbidites in continental margins: A case study from the Late Jurassic to Early Cretaceous Shelburne subbasin in offshore Nova Scotia.AAPG Bulletin 103: 2487-2520. [34] Mount, J F.1984. Mixing of siliciclastic and carbonate sediments in shallow shelf environments.Geology 12(7):432-435. [35] Mount J.F.1985. Mixed siliciclastic and carbonate sediments: a proposed first-order textural and compositional classification.Sedimentology 32: 435-442. [36] Parcell, W. C., Williams M K.2005. Mixed sediment deposition in a retroarc foreland basin: Lower Ellis Group (M. Jurassic),Wyoming and Montana,U.S.A.Sedimentary Geology 177: 175-194. [37] Rivera H.A., Le Roux J.P., Sanchez L.K., Marino-Martinez J.E., Salazar C., Barragan J.C.2018. Palaeoredox conditions and sequence stratigraphy of the Cretaceous storm-dominated, mixed siliciclastic-carbonate ramp in the Eastern Cordillera Basin (Colombia): Evidence from sedimentary geochemical proxies and facies analysis. Sedimentary Geology 372: 1-24. [38] Sanders, D., Pons, J. M.1999. Rudist formations in mixed siliciclastic-carbonate depositional environments, Upper Cretaceous, Austria:stratigraphy, sedimentology, and models of development.Palaeogeography, Palaeoclimatology, Palaeoecology148: 249-284. [39] Sanders, D., Hofling, R.2000. Carbonate deposition in mixed siliciclastic-carbonate environments on top of an orogenic wedge(Late Cretaceous, Northern Calcareous Alps, Austria).Sedimentary Geology 137: 127-146. [40] Sarkar S.,N. Chakraborty,A. Mandal,S. Banerjee,P.K. Bose.2014. Siliciclastic-carbonate mixing modes in the river-mouth bar palaeogeography of the Upper Cretaceous Garudamangalam Sandstone (Ariyalur, India).Journal of Palaeogeography 3(3):233-256. [41] Schellart, W.P., Lister, G.S.2005. The role of East Asian active margin in widespread and strike-slip deformation in East Asia.Journal of the Geological Society 162: 959-972. [42] Song Z.Q., Chen Y.F., Du X.F.2013. Research on mixed sedimentary characteristics and reservoir of second member of Shahejie Formation,A Area,Bohai Sea.Offshore Oil33(4): 13-18. (in Chinese with English abstract) [43] Tian L.X., Yu H., Zhou X.H., Peng W., Wang Y.2009. Major control factors of petroleum accumulation in Huanghekou Sag.Xinjiang Petroleum Geology 30, 319-321 (in Chinese with English abstract). [44] Tian L.X., Liu H., Niu C.M., Du X.F., Yang B., Lan X.D., Chen D.L.2019. Development characteristics and controlling factor analysis of the Neogene Minghuazhen Formation shallow water delta in Huanghekou area, Bohai offshore basin.Journal of Palaeogeography 8(1):19. [45] Wang G.Z.2001. Mixed sedimentation of recent reefoid carbonates and terrigenous clastics in the north continental shelf of the South China Sea.Journal of Palaeogeography 2(3): 48-49 (in Chinese with English abstract). [46] Wang J.Q., Liu B., Luo P.2014. Classificationg and genesis of Sinian mixosedimentite from northwest margin of Tarim Bain,China.Journal of Chendu University of Technology (Science & Technology Edition) 41(3): 339-346. (in Chinese with English abstract) [47] Yang, C.Q., Sha, Q.G.1990. Sedimentary environment of the middle Devonian Qujiang formation, Qujiang, Yunnan province: A kind of mixing sedimentation of terrigenous clastics and carbonate.Acta Sedimentological Sinica 8( 2): 59-65 (in Chinese with English abstract). [48] Yose, L A., Heller, P. L.1989. Sea-level control of mixed-carbonate-siliciclastic, gravity-flow deposition: Lower part of the Keeler Canyon Formation (Pennsylvanian), southeastern California. Geological Society of America Bulletin 101: 427-439. [49] Zhang, J.L., Si, X.Q.2007. Mixed Siliciclastic—carbonate Sediment in Rift Lacustrine Basin——a Case on the Upper Part of the Fourth Member of the Eogene Shahejie Formation in Jinjia Area, Dongying Depression.Geological Review 53(4): 448-454 (in Chinese with English abstract). [50] Zhang X.H.2000. Classification and origin of mixed imentite.Geological Science and Technology Information 19( 4) : 31-34. (in Chinese with English abstract) [51] Zhou X.H., Yu Y.X., Tang L.J., Lv D.Y., Wang Y.B.2010. Cenozoic offshore basin architecture and division of structural elements in Bohai Sea.China Offshore Oil and Gas 22, 285-289 (in Chinese with English abstract).