Influence of sedimentary environment on the properties of organic-rich shales in China: a review

Abstract

The sedimentary environment is inextricably linked to the macroscopic and microscopic characteristics of shale reservoirs, which influences shale gas accumulation significantly. This study discusses how the sedimentary environment affects the organic-matter-rich shale reservoirs that have been deposited in typical marine, marine-continental transitional, and continental basins in China. The following four aspects were analyzed including shale rock type and thickness distribution, organic matter abundance and distribution, mineral composition and pore structure, and kerogen type and hydrocarbon generation potential. From continental to marine facies, the sedimentary setting of shales with high organic content generally ranges from shore-shallow lakes to deep lakes, deltas, tidal flat lagoons, shallow sea shelves, and deep or semi-deep seas. In deeper water, the clay mineral content decreases, but the brittleness index and siliceous content increase with darker shale color. Thick shales mostly were deposited in deep or semi-deep lakes, delta fronts, prodeltas, tidal flat lagoons, and deep or semi-deep seas from continental to marine basins. The primary factors influencing organic matter enrichment in deep-sea and deep-lake shales are redox conditions and high biological productivity under favorable sedimentary environments, whereas favorable factors for organic matter enrichment in transitional facies include warm-humid palaeoclimates and abundant debris inputs. Continental shale is characterized by the presence of intergranular and intragranular pores, a low pore volume and specific surface area, and a high average pore size and hydrocarbon potential. The kerogen types are complex in continental shales, with type I in deep lake shales and type III in lakeshore shales. Transitional shales occur mostly in coal-bearing strata with type III organic content, medium pore sizes, and hydrocarbon generation potential. The high specific surface area and pore volume, small pore size, and high brittle mineral content of marine shale facilitate the production of dissolution pores. Marine shales are mainly kerogen type I–II₁ with relatively high maturity and low hydrocarbon production potential. By constructing an intrinsic link between the sedimentary environment and reservoir parameters, a sedimentary model of organic-rich shale under different depositional context should be summarized in the future, which can provide a foundation to analyze the geological circumstances of shale gas accumulation.

Graphical abstract

Keywords

organic-rich shale / sedimentary environment / shale gas / pore structure / shale gas distribution

References

[1] Boyer C, Clark B, Jochen V, Lewis R, Miller C K (2011). Shale gas: a global resource.Oilfield Rev, 23(3): 28–39

[2] BustinR M, BustinA, RossD, Chalmers G, MurthyV, LaxmiC, CuiX (2009). Shale gas opportunities and challenges. ln: AAPG Annual Convention, San Antonio, Texas, 20–23

[3] Cander H (2012). Sweet spots in shale gas and liquids plays: prediction of fluid composition and reservoir pressure.Search and Discovery Article, 40936: 12–15

[4] Cao D Y, Wang C J, Li J, Qin R F, Yang G, Zhou J (2014). Basic characteristics and accumulation rules of shale gas in coal measures.Coal Geol Explor, 42(4): 25–30

[5] Chen C, Mu C L, Zhou K K, Liang W, Ge X Y, Wang X P, Wang Q Y, Zheng B S (2016). The geochemical characteristics and factors controlling the organic matter accumulation of the Late Ordovician-Early Silurian black shale in the Upper Yangtze Basin, south China.Mar Pet Geol, 76: 159–175

[6] Chen D, Zhang J, Wang X, Lan B, Li Z, Liu T (2018). Characteristics of lacustrine shale reservoir and its effect on methane adsorption capacity in Fuxin Basin.Energy Fuels, 32(11): 11105–11117

[7] Chen J F, Zhang S C, Bao Z D, Sun S L, Wu Q Y (2006). Main sedimentary environments and influencing factors for development of marine organic-rich source rocks.Marine Origin Petrol Geo, 11(3): 49–54

[8] ChenR X (2002). The research of Cambrian system sequence stratigraphy in the Middle Yangtze area. Dissertation for Doctoral Degree. Xi’an: Northwest University

[9] Calvert S E (1987). Oceanographic controls on the accumulation of organic matter in marine sediments.Spec Publ Geol Soc Lond, 26(1): 137–151

[10] Dai H M, Huang D, Liu X M, Yang Y, He X M, Peng H R, Tong J W (2008). Characteristics and evaluation of marine source rock in southwestern Shunan.Nat Gas Geosci, 19(4): 503–508

[11] Demaison G J, Moore G T (1980). Anoxic environments and oils source bed genesis.Org Geochem, 64(1): 1179–1209

[12] Ding J H, Zhang J C, Shi G, Shen B J, Tang X, Yang Z H, Li X Q, Li C X (2021). Sedimentary environment and organic matter accumulation for the Longtan Formation shale in Xuancheng area.Acta Sediment Sin, 39(2): 324–340

[13] Doebbert A C, Carroll A R, Mulch A, Chetel L M, Chamberlain C P (2010). Geomorphic controls on lacustrine isotopic compositions: evidence from the Laney Member, Green River Formation, Wyoming.Geol Soc Am Bull, 122(1−2): 236–252

[14] Dong D Z, Cheng K M, Wang Y M, Li X J, Wang S J, Huang J L (2010). Forming conditions and characteristics of shale gas in the Lower Paleozoic of the Upper Yangtze region, China.Oil Gas Geol, 31(3): 288–299

[15] Dong D Z, Qiu Z, Zhang L F, Li S X, Zhang Q, Li X T, Zhang S R, Liu H L, Wang Y M (2021). Progress on sedimentology of transitional facies shales and new discoveries of shale gas.Acta Sediment Sin, 39(1): 29–45

[16] Dong D Z, Wang Y M, Huang X N, Zhang C C, Guan Q Z, Huang J L, Wang S F, Li X J (2016). Discussion about geological characteristics, resource evaluation methods and its key parameters of shale gas in China.Nat Gas Geosci, 27(9): 1583–1601

[17] Er C, Zhang J Z, Wang R, Wang Z K (2015). Controlling role of sedimentary environment on the distribution of organic-rich shale: A case study of the Chang7 member of the Triassic Yanchang Formation, Ordos Basin.Nat Gas Geosci, 26(5): 823–832

[18] Er C, Zhao J Z, Bai Y B, Fan H, Shen W X (2013). Reservoir characteristics of the organic-rich shales of the Triassic Yanchang Formation in Ordos Basin.Oil Gas Geol, 34(5): 708–716

[19] Feng Z Z, Peng Y M, Jin Z K, Jiang P L, Bao Z D, Luo Z, Ju T Y, Tian H Q, Wang H (2001). Lithofacies palaeogeography of the Cambrian in south China.J Palaeogeogr, 3(1): 1–14

[20] Fu X H, Zhang M, Zhang Q H, Zhu Y M, Guo Y H (2018). Evaluation index system for the Permo-Carboniferous mud shale reservoirs of coal measures in Shanxi province.J China Coal Soc, 43(6): 1654–1660

[21] Gao Z Y, Zhang S C, Li J J, Zhang B M, Gui Q Y, Lu Y H (2010). Distribution and sedimentary environments of Salgan and Yingan shales of the Middle-Upper Ordovician in western Tarim Basin.J Palaeogeogr, 12(5): 599–608

[22] Guan Q Z, Dong D Z, Wang S F, Huang J L, Wang Y M, Zhang C C (2016). Analyses on differences of microstructure between marine and lacustrine facies shale reservoirs.Nat Gas Geosci, 27(3): 524–531

[23] Guo S B, Wang Z L, Ma X (2021). Exploration prospect of shale gas with Permian transitional facies of some key areas in China.Petrol Geol Exper, 43(3): 377–385

[24] Guo Y H, Li Z F, Li D H, Zhang T M, Wang Z C, Yu J F, Xi Y T (2004). Lithofacies palaeogeography of the Early Silurian in Sichuan area.J Palaeogeogr, 6(1): 20–29

[25] Hou H H, Shao L Y, Li Y H, Li Z, Zhang W L, Wen H J (2018). The pore structure and fractal characteristics of shales with low thermal maturity from the Yuqia Coalfield, northern Qaidam Basin, northwestern China.Front Earth Sci, 12(1): 148–159

[26] Hou H H, Shao L Y, Li Y H, Liu L, Liang G D, Zhang W L, Wang X T, Wang W C (2022). Effect of paleoclimate and paleoenvironment on organic matter accumulation in lacustrine shale: constraints from lithofacies and element geochemistry in the northern Qaidam Basin, NW China.J Petrol Sci Eng, 208: 109350

[27] Hou H H, Shao L Y, Li Y H, Lu J, Li Z, Wang S, Zhang W L, Wen H J (2017). Geochemistry, reservoir characterization and hydrocarbon generation potential of lacustrine shales: a case of YQ-1 well in the Yuqia Coalfield, northern Qaidam Basin, NW China.Mar Pet Geol, 88: 458–471

[28] Hou H H, Shao L Y, Wang S, Xiao Z H, Wang X T, Li Z, Mu G Y (2019). Influence of depositional environment on coalbed methane accumulation in the Carboniferous-Permian coal of the Qinshui Basin, northern China.Front Earth Sci, 13(3): 535–550

[29] HouX W (2021). Study on gas controlling mechanism and coupled accumulation of deep coal measure gases in Qinshui Basin. Dissertation for Doctoral Degree Beijing: China University of Mining and Technology

[30] Hu B, Shang Y G, Niu Y B, Song H B, Liu S X, Zhang L (2012). Sequence stratigraphic framework of Late Paleozoic coal measures and their sedimentary evolution in Henan Province.Coal Geo Explor, 40(2): 1–5

[31] Huang G Z (2009). Exploration prospect of shale gas and coal-bed methane in Sichuan Basin.Litho Reserv, 21(2): 116–120

[32] Jia C Y, Jia A L, Han P L, Wang J J, Yuan H, Qiao H, Qiao H (2017). Reservoir characterization and development evaluation of organic-rich gas-bearing shale layers in the Lower Silurian Longmaxi Formation, Sichuan Basin.Nat Gas Geosci, 28(9): 1406–1415

[33] Jia J C (2007). Coal depositional system and its controlling role of coalbed methane in Late Paleozonic of Qinshui Basin.J Earch Sci Environ, 29(4): 374–382

[34] Jiang S, Wang Y M, Wang S Y, Peng P, Dong D Z, Wu W, Li X J, Guan Q Z (2018). Distribution prediction of graphitized organic matter areas in the Lower Cambrian Qiongzhusi shale in the central Sichuan paleo-uplift and its surrounding areas in the Sichuan Basin.Nat Gas Ind, 38(10): 19–27

[35] Jiang S, Xu Z, Feng Y, Zhang J, Cai D, Chen L, Wu Y, Zhou D, Bao S, Long S (2016). Geologic characteristics of hydrocarbon-bearing marine, transitional and lacustrine shales in China.J Asian Earth Sci, 115: 404–418

[36] Jiang Z X, Guo L, Liang C (2013). Lithofacies and sedimentary characteristics of the Silurian Longmaxi Shale in the southeastern Sichuan Basin, China.J Palaeogeogr, 2(3): 238–251

[37] Jiu K, Ding W L, Huang W H, Zhang J C, Zeng W T (2012). Formation environment and controlling factors of organic-rich shale of Lower Cambrian in upper Yangtze region.Geoscience, 26(3): 547–554

[38] Ju Y, Wang G, Bu H, Li Q, Yan Z (2014). China organic-rich shale geologic features and special shale gas production issues.J Rock Mech Geotech Eng, 6(3): 196–207

[39] Kang Y Z (2007). Reservoiring conditions and exploration direction for large scale Paleozoic oil and gas fields in China.Nat Gas Ind, 27(8): 1–5

[40] Lazar O R, Bohacs K M, Macquaker J H S, Schieber J, Demko T M (2015). Capturing key attributes of fine-grained sedimentary rocks in outcrops, cores, and thin sections: nomenclature and description guidelines.J Sediment Res, 85(3): 230–246

[41] Li J Q, Pu R H, Wu Y, Tian Y Y (2012a). Sedimentary characteristic and favorable reservoir prediction of Longtan Formation in Huangqiao area, Jiangsu Province.Petrol Geo Exper, 34(4): 395–399

[42] Li J Z, Li D H, Dong D Z, Wang S J (2012b). Comparison and enlightenment on formation condition and distribution characteristics of shale gas between China and US.Eng Sci, 14(6): 56–63

[43] Li J, Tao S Z, Wang Z C, Zou C, Gao X, Wang S Q (2010). Characteristics of Jurassic petroleum geology and main factors of hydrocarbon accumulation in NE Sichuan Basin.Nat Gas Geosci, 21(5): 732–741

[44] Li M W, Ma X X, Jin Z J, Li Z M, Jiang Q G, Wu S Q, Li Z, Xu Z X (2022). Diversity in the lithofacies assemblages of marine and lacustrine shale strata and significance for unconventional petroleum exploration in China.Oil Gas Geol, 43(1): 1–25

[45] Li M, Shao L, Lu J, Spiro B, Wen H, Li Y (2014). Sequence stratigraphy and paleogeography of the Middle Jurassic coal measures in the Yuqia coalfield, northern Qaidam Basin, northwestern China.AAPG Bull, 98(12): 2531–2550

[46] Li Q W, Pang X Q, Tang L, Chen G, Shao X H, Jia N (2018). Occurrence features and gas content analysis of marine and continental shales: a comparative study of Longmaxi Formation and Yanchang Formation.J Nat Gas Sci Eng, 56: 504–522

[47] Li T Y, He S, Yang Z (2008). The marine source rock formation conditions and control factors.Geol Sci Techn Inform, 27(6): 63–70

[48] LiW J (2014). Accumulation conditions and models of Permian shale gas in typical areas of China. Dissertation for Doctoral Degree. Beijing: China University of Geosciences

[49] Li W, Zhang Z H, Zhu L, Han L G, Yang Y C (2005). The history analysis of hydrocarbon expulsion from the coal beds in the Carboniferous-Permian in Qinshui Basin, Shanxi.Acta Sediment Sin, 23(2): 337–345

[50] Li Y F, Shao D Y, Lu H G, Zhang Y, Zhang X L, Zhang T W (2015). A relationship between elemental geochemical characteristics and organic matter enrichment in marine shale of Wufeng Formation—Longmaxi Formation, Sichuan Basin.Acta Petrol Sin, 36(12): 1470–1483

[51] Li Y J, Zhao S X, Huang Y B, Zhang L H, Zhang K, Tang H M (2013). The sedimentary micro-facies study of the Lower Cambrian Qiongzhusi Formation in southern Sichuan basin.Acta Petrol Sin, 87(8): 1136–1148

[52] LiY W (2017). Shale gas accumulation conditions and favourable area prediction of Lower Paleozoic in southern Henan. Dissertation for Doctoral Degree. Beijing: China University of Petroleum

[53] Li Z M, Zhang D, Zhang G B, Sima X Z, Liu Y J, Wang H, Wang C, Weng J C, Zhang C, Si Q H (2016). The transitional facies shale gas formation selection and favorable area prediction in the western Henan.Earth Sci Front, 23(2): 39–47

[54] Liang D G, Guo T L, Chen J P, Bian L Z, Zhao Z (2008). Some progresses on studies of hydrocarbon generation and accumulation in marine sedimentary regions, southern China (part 1): distribution of four suits of regional marine source rocks.Marine Origin Petrol Geo, 13(2): 1–16

[55] LiangY (2014). The comparative research on the characteristics of China typical marine and continental source rocks of shale gas. Dissertation for Doctoral Degree. Beijing: China University of Geosciences

[56] Liao Y T, Li F X, Yang Y X, Wang Y P, Hu Y G, Ma R F (2010). Preliminary exploration of excellent marine hydrocarbon in lower Cambrian on the south margin of the north China.Petrol Geol Eng, 24(4): 26–28

[57] Liu B, Wang F, Ran Q C, Li M, Dai C L, Wang M (2014). Characteristics of shale reservoir of the first member of Qingshankou Formation in northern Songliao Basin.Lithologic Reservoirs, 26(5): 64–68

[58] Liu C, Ding W G, Zhang J, Chen X, Wu P, Liu X Q, Li Y B, Ma L T, Hu W Q, K W, Li Y (2021). Qualitative-quantitative multi scale characteristics of shale pore structure from Upper Paleozoic coal-measures in Linxing area.Coal Geo Explor, 49(6): 46–57

[59] Liu D M, Li J Q, Li Z N (2013). Research on enrichment and accumulation mechanism of shale gas and its formation conditions in China.Coal Sci Technol, 41(9): 66–70

[60] Liu Q, Yuan X J, Lin S H, Guo H, Cheng D W (2018). Depositional environment and characteristic comparison between lacustrine mudstone and shale: a case study from the Chang 7 Member of the Yanchang Formation, Ordos Basin.Oil Gas Geol, 39(3): 531–540

[61] LiuS X (2018). Reservoir characteristics and sedimentary control mechanism of the marine-continental transitional mud shale: a case of the Longtan Formation in Zhina coalfield. Beijing: China University of Mining and Technology

[62] Liu Z J, Dong Q S, Ye S Q, Zhu J W, Guo W, Li D C, Liu R, Zhang H L, Du J F (2006). The situation of oil shale resources in China.J Jilin Univ (Earth Sci Ed), 36(6): 869–876

[63] Loucks R G, Reed R M, Ruppel S C, Hammes U (2012). Spectrum of pore types and networks in mudrocks and a descriptive classification for matrix-related mudrock pores.AAPG Bull, 96(6): 1071–1098

[64] Loucks R G, Ruppel S C (2007). Mississippian Barnett Shale: Lithofacies and depositional setting of a deep-water shale-gas succession in the Fort Worth Basin, Texas.AAPG Bull, 91(4): 579–601

[65] Luo W, Hou M C, Liu X C, Huang S G, Chao H, Zhang R, Deng X (2018). Geological and geochemical characteristic of marine-continental transitional shale from the Upper Permian Longtan formation, northwestern Guizhou, China.Mar Pet Geol, 89: 58–67

[66] MaL, ChenH J, GanK W, Xu K D, XuX S, WuG Y, YeZ, LiangX, Wu S H, QiuY Y, ZhangP L (2004). Geotectonics and Petroleum Geology of Marine Sedimentary Rocks in Southern China. Beijing: Geological Publishing House

[67] MaW Q (2017). Research on shale gas forming conditions of Chang 7 member of Yanchang Formation in Wuqi-Zhidan area, Ordos Basin. Dissertation for Doctoral Degree. Xi’an: Northwest University

[68] Ma Y S, Cai X Y, Zhao P R, Hu Z Q, Liu H M, Gao B, Wang W Q, Li Z M, Zhang Z L (2022). Geological characteristics and exploration practices of continental shale oil in China.Acta Geol Sin, 96(1): 155–171

[69] MaY S, ChenH D, WangG L (2009). Sequence Stratigraphy and Paleogeography of Southern China. Beijing: Science Press, 30–56

[70] MartinJ P, NyahayR, LeoneJ, Smith L B (2008). Developing a new gas resource in the heart of the northeastern USA Market: New York’s Utica Shale Play. In: Annual Meeting of the American Association of Petroleum Geologists. San Antonio, 20–23

[71] Mastalerz M, Schimmelmann A, Drobniak A, Chen Y (2013). Porosity of Devonian and Mississippian New Albany Shale across a maturation gradient: insights from organic petrology, gas adsorption, and mercury intrusion.AAPG Bull, 97(10): 1621–1643

[72] Mendhe V A, Mishra S, Varma A K, Kamble A D, Bannerjee M, Sutay T (2017). Gas reservoir characteristics of the lower Gondwana shales in Raniganj basin of eastern India.J Petrol Sci Eng, 149: 649–664

[73] Murphy A E, Sageman B B, Hollander D J, Lyons T W, Brett C E (2000). Black shale deposition and faunal overturn in the Devonian Appalachian Basin: Clastic starvation, seasonal water-column mixing, and efficient biolimiting nutrient recycling.Paleoceanography, 15(3): 280–291

[74] Nie H K, Ma X, Yu C, Ye X, Bian R K, Liu Z B (2017). Shale gas reservoir characteristics and its exploration potential-analysis on the Lower Jurassic shale in the eastern Sichuan Basin.Oil Gas Geol, 38(3): 438–447

[75] Niu Y B, Zhong J H, Duan H L, Yin C M, Wang P J (2010). Relationship between Carboniferous sedimentary facies and source rock in Qaidam Basin.Acta Sediment Sin, 28(1): 140–149

[76] NorstedB A, Carroll A R, SmithM E (2015). Initiation of Eocene lacustrine sedimentation in the greater Green River basin: Luman member of the Green River formation. In: Smith M E, Carroll A R, Eds., Stratigraphy and Paleolimnology of the Green River Formation. Dordrecht: Springer, 13–30

[77] Pan L, Xiao X, Tian H, Zhou Q, Chen J, Li T, Wei Q (2015). A preliminary study on the characterization and controlling factors of porosity and pore structure of the Permian shales in Lower Yangtze region, eastern China.Int J Coal Geol, 146: 68–78

[78] Panno S V, Hackley K C, Locke R A, Krapac I G, Wimmer B, Iranmanesh A, Kelly W R (2013). Formation waters from Cambrian-age strata, Illinois Basin, USA: constraints on their origin and evolution.Geochim Cosmochim Acta, 122: 184–197

[79] PengL (2017). Heterogeneity and controlling factors of lithofacies of the lower 3rd member of Paleogene Shahejie Formation lacustrine shale in Jiyang depression. Dissertation for Doctoral Degree. Wuhan: China University of Geosciences

[80] Qin J, Wang S, Sanei H, Jiang C, Chen Z, Ren S, Xu X, Yang J, Zhong N (2018). Revelation of organic matter sources and sedimentary environment characteristics for shale gas formation by petrographic analysis of middle Jurassic Dameigou formation, northern Qaidam Basin, China.Int J Coal Geol, 195: 373–385

[81] Ross D J, Bustin R M (2008). Characterizing the shale gas resource potential of Devonian–Mississippian strata in the Western Canada sedimentary basin: Application of an integrated formation evaluation.AAPG Bull, 92(1): 87–125

[82] Ross D J, Bustin R M (2009). The importance of shale composition and pore structure upon gas storage potential of shale gas reservoirs.Mar Pet Geol, 26(6): 916–927

[83] Sageman B B, Murphy A E, Werne J P, Straeten C A V, Hollander D J, Lyons T W (2003). A tale of shales: the relative roles of production, decomposition, and dilution in the accumulation of organic-rich strata, Middle-Upper Devonian, Appalachian Basin.Chem Geol, 195(1−4): 229–273

[84] ShaoL Y, HeZ P, LuJ (2008). Sequence Stratigraphy and Coal Accumulation of the Carboniferous and Permian in the Western Peri-Bohai Bay Area of the Northern China. Beijing: Geological Publishing House, 32–33

[85] Shao L Y, Li M, Li Y H, Zhang Y P, Lu J, Zhang W L, Tian Z, Wen H J (2014). Geological characteristics and controlling factors of shale gas in the Jurassic of the northern Qaidam Basin.Earth Sci Front, 21(4): 311–322

[86] Shao L Y, Liu L, Wen H J, Li Y H, Zhang W L, Li M (2016). Characteristics and influencing factors of nanopores in the Middle Jurassic Shimengou shale in well YQ-1 of the northern Qaidam Basin.Earth Sci Front, 23(1): 164–173

[87] Shao L Y, Xiao Z H, He Z P, Liu Y F, Shang L J, Zhang P F (2006). Palaeogeography and coal accumulation for coal measures of the Carboniferous-Permian in Qinshui Basin, southeastern Shanxi Province.J Palaeogeogr, 8(1): 43–52

[88] Shao L Y, Yang Z Y, Fang C, Wang S, Gu J Y, Zhang W L, Lu J (2021). Permo-carboniferous marine-terrestrial transitional facies coal measures shale gas geological conditions and exploration potential in Qinshui Basin.Coal Geol China, 33(10): 1–10

[89] Shao L Y, Yang Z Y, Shang X X, Xiao Z H, Wang S, Zhang W L, Zheng M Q, Lu J (2015). Lithofacies palaeogeography of Carboniferous and Permian in the Qinshui Basin, Shanxi Province, China.J Palaeogeogr, 4(4): 384–413

[90] Shao L Y, Zhang T C (2023). Discussion on definition and classification of mudrock.J Palaeogeogr, 25(4): 742–751

[91] Shen J, Qin Y, Zhang B, Li G Z, Shen Y L (2018). Superimposing gas-bearing system in coal measures and its compatibility in Linxing block, east Ordos Basin.J China Coal Soc, 43(6): 1614–1619

[92] Shi Z S, Wang H Y, Zhao S X, Zhou T Q, Zhao Q Q L (2023). Rapid transgressive shale characteristics and organic matter distribution of the Upper Ordovician-Lower Silurian Wufeng-Longmaxi Formations in southern Sichuan Basin, China.J Palaeogeogr, 25(4): 788–805

[93] Song D J, Tuo J C, Wang Y T, Wu C J, Zhang M H (2019). Research advances on characteristics of nanopore structure of organic-rich shales.Acta Sediment Sin, 37(6): 1309–1324

[94] SongJ J (2009). The study of Carboniferous-Permian sequence stratigraphic and coal accumulation in Henan Province. Dissertation for Doctoral Degree. Beijing: China University of Mining and Technology

[95] Song Y, Gao F L, Tang X L, Chen L, Wang X M (2020). Influencing factors of pore structure differences between marine and terrestrial shale reservoirs.Acta Petrol Sin, 41(12): 1501–1512

[96] Sun C R, Tang S H, Wei J G (2017). The differences of reservoir features between southern marine shale gas and northern coal-bearing shale gas in China.China Mining Mag, 26(3): 166–170

[97] Teng G R, Liu W H, Xu Y C, Chen J F (2004). Organic carbon isotope record in marine sediment and its environment significance–An example from Ordos Basin, NW China.Pet Explor Dev, 31(5): 11–16

[98] Tyson R V, Pearson T H (1991). Modern and ancient continental shelf anoxia.Geol Soc Lond Spec Publ, 58: 470–482

[99] Wang C, Zhang B Q, Shu Z G, Lu Y C, Lu Y Q, Bao H Y, Li Z, Liu C (2018). Lithofacies types and reservoir characteristics of marine shales of the Wufeng Formation-Longmaxi Formation in Fuling area, the Sichuan Basin.Oil Gas Geol, 39(3): 485–497

[100] Wang H Z, Li S T (2004). Tectonic Evolution of China and Its Control over Oil Basins.J Earth Sci, 15(1): 1–8

[101] Wang X Z, Gao S L, Gao C (2014). Geological features of Mesozoic lacustrine shale gas in south of Ordos Basin, NW China.Pet Explor Dev, 41(3): 326–337

[102] Wang Y M, Li X J, Dong D Z, Zhang C C, Wang S F (2017a). Main factors controlling the sedimentation of high-quality shale in Wufeng-Longmaxi Formation, Upper Yangtze region.Nat Gas Ind, 37(4): 9–20

[103] Wang Y, Chen J, Hu L, Zhu Y M (2013). Sedimentary environment control on shale gas reservoir: a case study of Lower Cambrian Qiongzhusi Formation in the Middle Lower Yangtze area.J China Coal Soc, 38(5): 845–850

[104] Wang Z, Fu X, Feng X, Song C, Wang D, Chen W, Zeng S (2017b). Geochemical features of the black shales from the Wuyu Basin, southern Tibet: implications for palaeoenvironment and palaeoclimate.Geol J, 52(2): 282–297

[105] Wei Z, Wang G, Wang Y, Ma X, Zhang T, He W, Yu X (2020). Geochemical and geological characterization of marine‐continental transitional shale: a case study in the Ordos Basin, NW China.Acta Geol Sin, 94(3): 809–821

[106] Wu H, Yao S P, Jiao K, Hu W X, Yin H W, Jia D (2013). Shale-gas exploration prospect of Longtan Formation in the Lower Yangtze area of China.J China Coal Soc, 38(5): 870–876

[107] XinQ, LuoM F (2009). Modern Catalysis Research Methods. Beijing: Science Press

[108] Xiong D M, Ma W Y, Zhang M F, Wu C J, Tuo J C (2014). New method for the determination of kerogen type and the hydrocarbon potential.Nat Gas Geosci, 25(6): 898–905

[109] Yan D Y, Huang W H, Lu X X, Yin X D, Shi Y L (2016). Contrast of reservoir-forming conditions of marine-continental transitional shale gas in different sedimentary environments in the Lower Yangtze area of China.J China Coal Soc, 41(7): 1778–1787

[110] Yan J Q, Hu C L, Tian J J, Shi H C, Duan W G, Zhang X C (2022). Organic matter enrichment mechanism in Wufeng Formations to Longyi member: A case study from YS112 well in Sichuan Basin.Chn J Geo, 57(2): 439–462

[111] Yang H, Dou W T, Liu X Y, Zhang C L (2010). Analysis on sedimentary facies of member 7 in Yanchang Formation of Triassic in Ordos Basin.Acta Sediment Sin, 28(2): 254–263

[112] Yang S Y, Wei G J, Shi X F (2015). Geochemical approaches of tracing source-to-sink sediment processes and environmental changes at the East Asian continental margin.Bull Miner Petrol Geochem, 34(5): 902–910

[113] Yang X, Guo S (2020). Pore characterization of marine-continental transitional shale in Permian Shanxi Formation of the southern north China basin.Energy Explor Exploit, 38(6): 2199–2216

[114] Yang Y T, Zhang J C, Wang X Z, Cao J Z, Tang X, Wang L, Yang S Y (2012). Source rock evaluation of continental shale gas: a case study of Chang 7 of Mesozoic Yanchang Formation in Xia Siwan area of Yanchang.J Northwest Petrol Univ, 36(4): 10–17

[115] Ye J, Zeng H S (2008). Pooling conditions and exploration prospect of shale gas in Xujiahe Formation in western Sichuan depression.Nat Gas Ind, 28(12): 18–25

[116] YuQ (2020). Sedimentary control factors of mud shale development in Shanxi Formation of Qinshui Basin. Dissertation for Doctoral Degree. Beijing: China University of Geosciences

[117] Yuan X J, Lin S H, Liu Q, Yao J L, Wang L, Guo H, Deng X Q, Cheng D W (2015). Lacustrine fine-grained sedimentary features and organic-rich shale distribution pattern: A case study of Chang 7 Member of Triassic Yanchang Formation in Ordos Basin, NW China.Pet Explor Dev, 42(1): 34–43

[118] ZengQ N (2013a). Characteristics and evaluation of the organic-rich shale reservoirs of Yanchang Formation, southeast in Ordos Basin. Dissertation for Doctoral Degree. Beijing: China University of Geosciences

[119] Zeng W T, Ding W L, Zhang J C, Li C, Xu C C, Jiu K, Wu L M (2013b). Analysis of geological controls on shale gas accumulation in northwest China.Bull Geol Sci Techn, 32(4): 139–150

[120] Zeng W T, Zhang J C, Ding W L, Wang X Z, Zhu D W, Liu Z J (2014). The gas content of continental Yanchang shale and its main controlling factors: a case study of Liuping-171 well in Ordos Basin.Nat Gas Geosci, 25(2): 291–301

[121] Zhang C M, Zhang W S, Guo Y H (2012). Sedimentary environment and its effect on hydrocarbon source rocks of Longmaxi Formation in southeast Sichuan and northern Guizhou.Earth Sci Front, 19(1): 136–145

[122] Zhang J Y, Lu Y C, Fu X Y, Zhang S W (2017). Sequence stratigraphic framework and sedimentary evolution of the Wufeng Formation-the 1st member of Longmaxi Formation in Fuling area, Sichuan Basin.Bull Geol Sci Techn, 36(4): 65–72

[123] Zhang J Z, Li X Q, Wang Y, Fu Q H, Cai Y Q, Niu H Y (2015). Accumulation conditions and reservoir characteristics of marine-terrigenous facies coal measures shale gas from Longtan Formation in south Sichuan Basin.J China Coal Soc, 40(8): 1871–1878

[124] Zhang L C, Xiao D S, Lu S F, Jiang S, Lu S D (2019). Effect of sedimentary environment on the formation of organic-rich marine shale: Insights from major/trace elements and shale composition.Int J Coal Geol, 204: 34–50

[125] Zhang M Z, Zhu X M, Jiang Z X, Zhu D Y, Ye L, Shen Z Y (2023). Main controlling factors of organic matter enrichment in continental freshwater lacustrine shale: a case study of the Jurassic Ziliujing Formation in northeastern Sichuan Basin.J Palaeogeogr, 25(4): 806–822

[126] ZhangS B, NiY N, GongF H, Lu H N, HuangZ B, LinH L (2003). A Guide to the Stratigraphic Investigation on the Periphery of the Tarim Basin. Beijing: Petroleum Industry Press

[127] Zhang X G (1993). The distribution of sedimentary facies in the Cambrian system of the Yangtze area.Petrol Geol Experiment, 15(4): 350–360

[128] Zhang X L, Li Y F, Lu H G, Yan J P, Tuo J C, Zhang T W (2013). Relationship between organic matter characteristics and depositional environment in the Silurian Longmaxi Formation in Sichuan Basin.J China Coal Soc, 38(5): 851–856

[129] Zhao D F, Guo Y H, Bai W B, Ye Z Y, Cao L, Li G, Wang X L (2018). Controlling mechanism of sedimentary environment on high quality shale reservoir: Taking shale reservoirs of Longmaxi formation in southeast Chongqing as an example.J Henan Polytechn Univ, 37(4): 37–47

[130] Zhao W Z, Jia A L, Wei Y S, Wang J L, Zhu H Q (2020). Progress in shale gas exploration in China and prospects for future development.China Petrol Explor, 25(1): 31–44

[131] Zhou D H, Sun C X, Liu Z B, Nie H K (2020). Geological characteristics of continental shale gas reservoir in the Jurassic Da’anzhai member in the northeastern Sichuan Basin.China Petrol Explor, 25(5): 32–42

[132] Zhu G Y, Su J, Yang H J, Wang Y, Fei A G, Liu K Y, Zhu Y F, Hu J F, Zhang B S (2013). Formation mechanisms of secondary hydrocarbon pools in the Triassic reservoirs in the northern Tarim Basin.Mar Pet Geol, 46: 51–66

[133] Zhu T, Yu L J, Wang F (2017). Comparative analysis of the accumulation conditions and development strategies of the marine and lacustrine shale gas from the Sichuan Basin, China.Nat Gas Geosci, 28(4): 633–641

[134] Zou C, Dong D, Wang S, Li J, Li X, Wang Y, Li D, Cheng K (2010). Geological characteristics and resource potential of shale gas in China.Pet Explor Dev, 37(6): 641–653

[135] Zou C N, Dong D Z, Yang H, Wang Y M, Huang J L, Wang S F, Fu C X (2011). Conditions of shale gas accumulation and exploration practices in China.Nat Gas Ind, 31(12): 26–39

[136] Zou C N, Zhao Q, Dong D Z, Yang Z, Qiu Z, Liang F, Wang N, Huang Y, Duan A X, Zhang Q, Hu Z M (2017). Geological characteristics, main challenges and future prospect of shale gas.Nat Gas Geosci, 2(5−6): 1781–1796

[137] Zou C N, Zhu R K, Dong D Z, Wu S T (2022). Scientific and technological progress, development strategy and policy suggestion regarding shale oil and gas.Acta Petrol Sin, 43(12): 1675–1686

[138] ZuoR S (2019). The development model of Xujiahe continental shale in Western Sichuan depression and its reservoir characteristics. Dissertation for Doctoral Degree. Beijing: China University of Petroleum

Acknowledgments

This research was financially supported by the National Natural Science Foundation of China (Grant No. 42102223) and the China Postdoctoral Science Foundation (Nos. 2021M693844, 2022T150284). The authors are also grateful for the careful and valuable comments from the anonymous reviewers.

Competing interests

The authors declare that they have no competing interests.

RIGHTS & PERMISSIONS

2024 Higher Education Press