Constraints of palaeoenvironment on organic matter of Benxi Formation shale and discussion on enrichment mechanism under different facies

Abstract

As a hydrocarbon-rich sedimentary basin in China, the Ordos Basin has enormous potential for shale gas resources. The shale of the Upper Carboniferous Benxi Formation is rich in organic matter, however, its palaeoenvironment and organic matter enrichment mode are yet to be revealed. In this study, the geochemical characteristics of the shale of the Benxi Formation in the east-central part of the Ordos Basin were analyzed to investigate its palaeoenvironment. At the same time, the organic matter enrichment modes in different sedimentary facies were compared and analyzed. The results indicate that: 1) the shale of the Benxi Formation was mainly deposited on the continental margin and strong terrestrial clastic input; 2) the deposition period of the Benxi Formation shale had a hot and humid climate with high palaeoproductivity and local volcanic hydrothermal fluid, and a high sedimentation rate with the strong stagnant environment. The bottom water was in dysoxic conditions and a semi-saline deposition environment; 3) multiple factors, such as palaeoproductivity, volcanic hydrothermal, redox conditions, and palaeosalinity interact to influence the enrichment of shale organic matter in Benxi Formation; 4) the organic matter enrichment modes of continental, marine-continental transitional, and marine shales can be classified into three types: “production mode”, “hybrid mode of preservation and production”, and “preservation mode”, respectively. This study provides a reference for the organic matter enrichment mode, shale gas formation conditions, and core area evaluation in these marine-continental transitional shales, and also offers new guidance for exploration ideas for shale gas in different sedimentary facies.

Graphical abstract

Keywords

Benxi Formation / shale / palaeoenvironment / organic matter enrichment / facies

References

[1] Abanda P A, Hannigan R E (2006). Effect of diagenesis on trace element partitioning in shales.Chem Geol, 230(1–2): 42–59

[2] AlgeoT J, RoweH (2012). Paleoceanographic applications of trace-metal concentration data. Chem Geol, 324–325: 6–18

[3] Algeo T J, Tribovillard N (2009). Environmental analysis of paleoceanographic systems based on molybdenum-uranium covariation.Chem Geol, 268(3–4): 211–225

[4] Awan R S, Liu C, Gong H, Dun C, Tong C, Chamssidini L G (2020). Paleo-sedimentary environment in relation to enrichment of organic matter of Early Cambrian black rocks of Niutitang Formation from Xiangxi area China.Mar Pet Geol, 112: 104057

[5] Bernárdez P, Gonzalez-Alvarez R, Frances G, Prego R, Barcena M A, Romero O E (2008). Late Holocene history of the rainfall in the NW Iberian peninsula - evidence from a marine record.J Mar Syst, 72(1–4): 366–382

[6] Chen Y, Liu S, Zhu Z, Wang Z, Sun X, Xu T (2021). Geochemical characteristics and sedimentary setting of chang 9 shale in the Upper Triassic Yanchang Formation of southeastern Ordos Basin (NW China).J Petrol Sci Eng, 196: 108081

[7] Chen Y, Wang Y, Guo M, Wu H, Li J, Wu W, Zhao J (2020). Differential enrichment mechanism of organic matters in the marine-continental transitional shale in northeastern Ordos Basin, China: control of sedimentary environments.J Nat Gas Sci Eng, 83: 103625

[8] Chen Y, Zhu Z, Zhang L (2019). Control actions of sedimentary environments and sedimentation rates on lacustrine oil shale distribution, an example of the oil shale in the Upper Triassic Yanchang Formation, southeastern Ordos Basin (NW China).Mar Pet Geol, 102: 508–520

[9] CuiC, ZhangH, LiuW, LiS, LiuY, SongH, WuC M, Wen Z (2022). Element geochemical characteristics of shale in the first member of Benxi Formation in eastern Ordos Basin:take Zhaoxian section and M115 well in Linxian County, Shanxi as examples. Nat Gas Geosci, 33(6): 1001–1012 (in Chinese)

[10] Cullers R L, Podkovyrov V N (2002). The source and origin of terrigenous sedimentary rocks in the Mesoproterozoic Ui group, southeastern Russia.Precambrian Res, 117(3–4): 157–183

[11] Ding W, Zhu D, Cai J, Gong M, Chen F (2013). Analysis of the developmental characteristics and major regulating factors of fractures in marine-continental transitional shale-gas reservoirs: a case study of the Carboniferous-Permian strata in the southeastern Ordos Basin, central China.Mar Pet Geol, 45: 121–133

[12] Ding X, Liu G, Zha M, Huang Z, Gao C, Lu X, Sun M, Chen Z, Liuzhuang X (2015). Relationship between total organic carbon content and sedimentation rate in ancient lacustrine sediments, a case study of Erlian basin, northern China.J Geochem Explor, 149: 22–29

[13] Doner Z, Kumral M, Demirel I H, Hu Q (2019). Geochemical characteristics of the Silurian shales from the central Taurides, southern Turkey: organic matter accumulation, preservation and depositional environment modeling.Mar Pet Geol, 102: 155–175

[14] Dong Z, Zhang J, Tang X, Liu G, Dang W, Liu Y, Tao J, Su Z (2020). Origin and diffusion of the over-mature transitional natural gas in multiple lithologic reservoirs: a case study of Carboniferous-Permian strata in the southeastern margin of Ordos Basin.Int J Coal Geol, 219: 103380

[15] Dypvik H, Harris N B (2001). Geochemical facies analysis of fine-grained siliciclastics using Th/U, Zr/Rb and (Zr+Rb)/Sr ratios.Chem Geol, 181(1–4): 131–146

[16] Elderfield H, Greaves M J (1982). The rare earth elements in seawater.Nature, 296(5854): 214–219

[17] Fedo C M, Wayne Nesbitt H, Young G M (1995). Unraveling the effects of potassium metasomatism in sedimentary rocks and paleosols, with implications for paleoweathering conditions and provenance.Geology, 23(10): 921–924

[18] Floyd P A, Leveridge B E (1987). Tectonic environment of the Devonian Gramscatho basin, south Cornwall: framework mode and geochemical evidence from turbiditic sandstones.J Geol Soc London, 144(4): 531–542

[19] GuoH (2020). Study on the Mechanism and Controlling Factors of Shale Gas Enrichment in Shanxi Formation-a Case Study of the Eastern Ordos Basin. Dissertation for Master Degree. Xi᾽an Shiyou University (in Chinese)

[20] HaskinL A, HaskinM A, FreyF A, Wildeman T R (1968). Relative and absolute terrestrial abundances of the rare earths. In: Ahrens L H, ed. Origin Distribution of the Elements. Elsevier, 889–912

[21] Hatch J R, Leventhal J S (1992). Relationship between inferred redox potential of the depositional environment and geochemistry of the Upper Pennsylvanian (Missourian) Stark Shale Member of the Dennis Limestone, Wabaunsee County, Kansas, U.S.A.Chem Geol, 99(1–3): 65–82

[22] He Q, Li D, Sun Q, Wei B, Wang S (2022). Main controlling factors of marine shale compressive strength: a case study on the Cambrian Niutitang Formation in Dabashan Mountain.Energy, 260: 125100

[23] He T, Lu S, Li W, Tan Z, Zhang X (2018). Effect of salinity on source rock formation and its control on the oil content in shales in the Hetaoyuan Formation from the Biyang Depression, Nanxiang Basin, Central China.Energy Fuels, 32(6): 6698–6707

[24] Hoyle J, Elderfield H, Gledhill A, Greaves M (1984). The behaviour of the rare earth elements during mixing of river and sea waters.Geochim Cosmochim Acta, 48(1): 143–149

[25] Hu T, Pang X, Jiang S, Wang Q, Xu T, Lu K, Huang C, Chen Y, Zheng X (2018). Impact of paleosalinity, dilution, redox, and paleoproductivity on organic matter enrichment in a saline lacustrine rift basin: a case study of paleogene organic-rich shale in Dongpu Depression, Bohai Bay Basin, eastern China.Energy Fuels, 32(4): 5045–5061

[26] Hu Y, Liu Y, Guo Y, Liu W, Zhang Z, Yang X (2022). Elemental geochemical characteristics of mudstones in Upper Carboniferous Benxi Formationin southern Ordos Basin and their enlightenment to sedimentary environment.J Shandong U Sci Techn (Nat Sci), 41: 13–23

[27] Jenkyns H C, Dickson A J, Ruhl M, Boorn S H J M (2017). Basalt-seawater interaction, the Plenus Cold Event, enhanced weathering and geochemical change: deconstructing Oceanic Anoxic Event 2 (Cenomanian-Turonian, Late Cretaceous).Sedimentology, 64(1): 16–43

[28] Jones B, Manning D A C (1994). Comparison of geochemical indices used for the interpretation of palaeoredox conditions in ancient mudstones.Chem Geol, 111(1–4): 111–129

[29] Khaled A, Li R, Xi S, Zhao B, Wu X, Yu Q, Zhang Y, Li D (2022). Paleoenvironmental conditions and organic matter enrichment of the Late Paleoproterozoic Cuizhuang Formation dark shale in the Yuncheng Basin, north China.J Petrol Sci Eng, 208: 109627

[30] Lan Z, Shen J (2022). Depositional Paleo-environments of Lower Cambrian Qiongzhusi Formation in the western middle Yangtze Block and its controlling effect on the organic matter enrichment.Energies, 15(10): 3761

[31] Latimer J C, Filippelli G M (2002). Eocene to Miocene terrigenous inputs and export production: geochemical evidence from ODP Leg 177, Site 1090.Palaeogeogr Palaeoclimatol Palaeoecol, 182(3–4): 151–164

[32] Li D, Li R, Tan C, Zhao D, Xue T, Zhao B, Khaled A, Liu F, Xu F (2019a). Origin of silica, paleoenvironment, and organic matter enrichment in the Lower Paleozoic Niutitang and Longmaxi formations of the northwestern Upper Yangtze Plate: significance for hydrocarbon exploration.Mar Pet Geol, 103: 404–421

[33] Li W, Li J, Lu S, Chen G, Pang X, Zhang P, He T (2022). Evaluation of gas-in-place content and gas-adsorbed ratio using carbon isotope fractionation model: a case study from Longmaxi shales in Sichuan Basin, China.Int J Coal Geol, 249: 103881

[34] LiW, ZhangQ, LiK, ChenQ, GuoY, MaY, FengJ, Zhang D (2021). Sedimentary evolution of the late Paleozoic in Ordos Basin and its adjacent areas. J Palaeogeogr, 23: 39–52 (in Chinese)

[35] Li X, Gang W, Yao J, Gao G, Wang C, Li J, Liu Y, Guo Y, Yang S (2020). Major and trace elements as indicators for organic matter enrichment of marine carbonate rocks: a case study of Ordovician subsalt marine formations in the central-eastern Ordos Basin, north China.Mar Pet Geol, 111: 461–475

[36] Li Y, Gao X, Meng S, Wu P, Niu X, Qiao P, Elsworth D (2019c). Diagenetic sequences of continuously deposited tight sandstones in various environments: a case study from upper Paleozoic sandstones in the Linxing area, eastern Ordos basin, China.AAPG Bull, 103(11): 2757–2783

[37] Li Y, Wang Z, Gan Q, Niu X, Xu W (2019b). Paleoenvironmental conditions and organic matter accumulation in Upper Paleozoic organic-rich rocks in the east margin of the Ordos Basin, China.Fuel, 252: 172–187

[38] Liang J, Tao W, Ma X (2020). Origin and paleoenvironmental reconstruction of phosphorus-bearing sandstones of the Cambrian Xinji Formation, southwestern margin of the Ordos Basin, China.Can J Earth Sci, 57(8): 903–917

[39] Liu S, Wu C, Li T, Wang H (2018). Multiple geochemical proxies controlling the organic matter accumulation of the marine-continental transitional shale: a case study of the Upper Permian Longtan Formation, western Guizhou, China.J Nat Gas Sci Eng, 56: 152–165

[40] Ma Y, Lu Y, Liu X, Zhai G, Wang Y, Zhang C (2019). Depositional environment and organic matter enrichment of the lower Cambrian Niutitang shale in western Hubei Province, South China.Mar Pet Geol, 109: 381–393

[41] McLennanS M (2001). Relationships between the trace element composition of sedimentary rocks and upper continental crust. Geochem Geophys Geosyst, 2(4): n/a

[42] Meng Q, Liu Z, Bruch A A, Liu R, Hu F (2012). Palaeoclimatic evolution during Eocene and its influence on oil shale mineralisation, Fushun basin, China.J Asian Earth Sci, 45: 95–105

[43] Nesbitt H W, Young G M (1982). Early Proterozoic climates and plate motions inferred from major element chemistry of lutites.Nature, 299(5885): 715–717

[44] PetersK E, CassaM R (1994). Applied source rock geochemistry: Chapter 5: Part II. Essential Elements, 93–120

[45] Qi H W, Hu R Z, Su W C, Qi L, Feng J Y (2004). Continental hydrothermal sedimentary siliceous rock and genesis of superlarge germanium (Ge) deposit hosted in coal: a study from the Lincang Ge deposit, Yunnan, China.Sci China Ser D Earth Sci, 47(11): 973–984

[46] Rimmer S M (2004). Geochemical paleoredox indicators in Devonian-Mississippian black shales, central Appalachian basin (USA).Chem Geol, 206(3–4): 373–391

[47] Rimmer S M, Thompson J A, Goodnight S A, Robl T L (2004). Multiple controls on the preservation of organic matter in Devonian-Mississippian marine black shales: geochemical and petrographic evidence.Palaeogeogr Palaeoclimatol Palaeoecol, 215(1–2): 125–154

[48] Roser B, Korsch R J T J G (1986). Determination of tectonic setting of sandstone-mudstone suites using SiO₂ content and K₂O/Na₂O ratio.J Geol, 94(5): 635–650

[49] Scotese C R, Song H, Mills B J W, van der Meer D G (2021). Phanerozoic paleotemperatures: the earth’s changing climate during the last 540 million years.Earth Sci Rev, 215: 103503

[50] Shi Q, Li C, Wang S, Li D, Wang S, Du F, Qiao J, Cheng Q (2022). Effect of the depositional environment on the formation of tar-rich coal: a case study in the northeastern Ordos Basin, China.J Petrol Sci Eng, 216: 110828

[51] Song H, Wang H, Wang F, Guo R, Hu B (2016). Ichnofossils and ichnofabrics in the Lower Permian Taiyuan Formation of North China Basin.Geodin Acta, 28(1–2): 37–52

[52] Stock C A, John J G, Rykaczewski R R, Asch R G, Cheung W W L, Dunne J P, Friedland K D, Lam V W Y, Sarmiento J L, Watson R A (2017). Reconciling fisheries catch and ocean productivity.Proc Natl Acad Sci USA, 114(8): E1441–E1449

[53] Stüben D, Kramar U, Berner Z, Stinnesbeck W, Keller G, Adatte T (2002). Trace elements, stable isotopes, and clay mineralogy of the Elles II K-T boundary section in Tunisia: indications for sea level fluctuations and primary productivity.Palaeogeogr Palaeoclimatol Palaeoecol, 178(3–4): 321–345

[54] Talbot M R (1988). The origins of lacustrine oil source rocks: evidence from the lakes of tropical Africa. Geological Society. 40(6): 29–43

[55] TangD, ShiX, ZhaoX, Wang X, SongG (2015). Mo-U Covariation as an important proxy for sedimentary environment redox conditionsprogress, problems and prospects. Geoscience, 29(1): 1 (in Chinese)

[56] TangX, ZhangJ, WangX, Yu B, DingW, XiongJ, YangY, WangL, Yang C (2014). Shale characteristics in the southeastern Ordos Basin, China: implications for hydrocarbon accumulation conditions and the potential of continental shales. Int J Coal Geol, 128–129: 32–46

[57] TaylorS R, McLennan S M (1985). The Continental Crust: Its Composition and Evolution. Blackwell Scientific Pub

[58] Taylor S R, McLennan S M (1995). The geochemical evolution of the continental crust.Rev Geophys, 33(2): 241–265

[59] Tenger , Liu W, Xu Y, Chen J (2006). Comprehensive geochemical identification of highly evolved marine carbonate rocks as hydrocarbon-source rocks as exemplified by the Ordos Basin.Sci China Ser D Earth Sci, 49(4): 384–396

[60] Tribovillard N, Algeo T J, Lyons T, Riboulleau A (2006). Trace metals as paleoredox and paleoproductivity proxies: an update.Chem Geol, 232(1–2): 12–32

[61] Tyson R V (2001). Sedimentation rate, dilution, preservation and total organic carbon: some results of a modelling study.Org Geochem, 32(2): 333–339

[62] Wang Q, Jiang F, Ji H, Jiang S, Liu X, Zhao Z, Wu Y, Xiong H, Li Y, Wang Z (2020). Effects of paleosedimentary environment on organic matter enrichment in a saline lacustrine rift basin - A case study of Paleogene source rock in the Dongpu Depression, Bohai Bay Basin.J Petrol Sci Eng, 195: 107658

[63] Wedepohl K J P, Earth C (1971). Environmental influences on the chemical composition of shales and clays.Phys Chem Earth, 8: 307–333

[64] Wei Z, Wang Y, Wang G, Zhang T, He W, Ma X, Yu X (2020). Enrichment mechanism of the Upper Carboniferous-Lower Permian transitional shale in the east margin of the Ordos Basin, China: evidence from geochemical proxies.Geofluids, 2020: 1–14

[65] Wignall P B, Twitchett R J (1996). Oceanic anoxia and the end Permian mass extinction.Science, 272(5265): 1155–1158

[66] Wu J, Zhang Y, Zhou H (2020). Groundwater chemistry and groundwater quality index incorporating health risk weighting in Dingbian County, Ordos basin of northwest China.Chem Erde, 80(4): 125607

[67] Wu Y, Liu C, Liu Y, Gong H, Awan R S, Li G, Zang Q (2022a). Geochemical characteristics and the organic matter enrichment of the Upper Ordovician Tanjianshan Group, Qaidam Basin, China.J Petrol Sci Eng, 208: 109383

[68] Wu Z, He S, He Z, Li X, Zhai G, Huang Z (2022b). Petrographical and geochemical characterization of the Upper Permian Longtan formation and Dalong Formation in the Lower Yangtze region, South China: implications for provenance, paleoclimate, paleoenvironment and organic matter accumulation mechanisms.Mar Pet Geol, 139: 105580

[69] Wu Z, Zhao X, Li J, Pu X, Tao X, Shi Z, Sun Y (2021). Paleoenvironmental modes and organic matter enrichment mechanisms of lacustrine shale in the Paleogene Shahejie Formation, Qikou Sag, Bohai Bay Basin.Energy Rep, 7: 9046–9068

[70] Xu L, Huang S, Liu Z, Zhang Y, Wen Y, Zhou X, Chen W, Ren Z, Wen J (2022). Paleoenvironment evolutionary characteristics of Niutitang shale in Western Hubei, Middle Yangtze, China.ACS Omega, 7(28): 24365–24383

[71] Xu L, Lehmann B, Zhang X, Zheng W, Meng Q (2014). Trace element distribution in black shales from the Kunyang phosphorite deposit and its geological significances.Acta Petrol Sin, 30: 1817–1827

[72] Yamamoto K (1987). Geochemical characteristics and depositional environments of cherts and associated rocks in the Franciscan and Shimanto Terranes.Sediment Geol, 52(1–2): 65–108

[73] Yang K, Zhang B, Yao Y, Yang H, Zhang H, Xiao W, Wang Y (2022). Organic matter accumulation mechanism and characteristics in marine-continental transitional shale: a case study of the upper Permian Longtan Formation from the Well F5 in Sichuan Basin, China.J Petrol Sci Eng, 208: 109604

[74] Yang R, Ma T, Liu W, Fang Y, Xing L (2019). Coupled hydro-mechanical analysis of gas production in fractured shale reservoir by random fracture network modeling.Int J Appl Mech, 11(3): 1950031

[75] Yang X, Yan D, Zhang B, Zhang L, Wei X, Li T, He J, Shangguan Y, Zhang M, She X (2020). The depositional mechanism of organic-rich siliceous shales in Upper Yangtze area: response to the Kwangsian Orogeny in south China.J Petrol Sci Eng, 192: 107310

[76] Yang Y T, Li W, Ma L (2005). Tectonic and stratigraphic controls of hydrocarbon systems in the Ordos Basin: a multicycle cratonic basin in central China.AAPG Bull, 89(2): 255–269

[77] Yu W, Tian J, Wang F, Liang Q, Yang T, Kneller B, Liang X (2022). Sedimentary environment and organic matter enrichment of black mudstones from the upper Triassic Chang-7 member in the Ordos Basin, northern China.J Asian Earth Sci, 224: 105009

[78] Zeng S, Wang J, Fu X, Chen W, Feng X, Wang D, Song C, Wang Z (2015). Geochemical characteristics, redox conditions, and organic matter accumulation of marine oil shale from the Changliang Mountain area, northern Tibet, China.Mar Pet Geol, 64: 203–221

[79] Zhang K, Li Z, Jiang S, Jiang Z, Wen M, Jia C, Song Y, Liu W, Huang Y, Xie X, Liu T, Wang P, Shan C, Wu Y (2018a). Comparative analysis of the siliceous source and organic matter enrichment mechanism of the Upper Ordovician-Lower Silurian Shale in the Upper-Lower Yangtze Area.Minerals (Basel), 8(7): 283

[80] Zhang L, Kou Z, Wang H, Zhao Y, Dejam M, Guo J, Du J (2018b). Performance analysis for a model of a multi-wing hydraulically fractured vertical well in a coalbed methane gas reservoir.J Petrol Sci Eng, 166: 104–120

[81] Zhang L, Zhao Q, Peng S, Qiu Z, Feng C, Zhang Q, Wang Y, Dong D, Zhou S (2021). Paleoenvironment and organic matter accumulation mechanism of marine-continental transitional shales: outcrop characterizations of the Carboniferous-Permian strata, Ordos Basin, north China.Energies, 14(21): 7445

[82] Zhang P, Yang M, Lu J, Shao L, Wang Z, Hilton J (2022). Low-latitude climate change linked to high-latitude glaciation during the late paleozoic ice age: evidence from terrigenous detrital kaolinite.Front Earth Sci (Lausanne), 10: 956861

[83] Zhang W, Yang H, YangY , Kong Q, Wu K (2008). Petrology and element geochemistry and development environment of Yanchang Formation Chang-7 high quality source rocks in Ordos Basin.Geochimica, 37(1): 59–64

[84] Zhang W, Yang W, Xie L (2017). Controls on organic matter accumulation in the Triassic Chang 7 lacustrine shale of the Ordos Basin, central China.Int J Coal Geol, 183: 38–51

[85] Zhao B, Li R, Qin X, Wang N, Zhou W, Khaled A, Zhao D, Zhang Y, Wu X, Liu Q (2021). Geochemical characteristics and mechanism of organic matter accumulation of marine-continental transitional shale of the lower permian Shanxi Formation, southeastern Ordos Basin, north China.J Petrol Sci Eng, 205: 108815

[86] Zhou T, Zhou Y, Zhao H, Li M, Mu H (2022). Depositional setting and enrichment mechanism of organic matter of Lower Cretaceous shale in Ri-Qing-Wei Basin in the Central Sulu Orogenic Belt.Front Earth Sci (Lausanne), 9: 808916

RIGHTS & PERMISSIONS

Higher Education Press