Nanoscale Pore Characteristics of the Upper Permian Mudrocks from a Transitional Environment in and around Eastern Sichuan Basin, China
|
摘要
Nanoscale pore characteristics of the Upper Permian Longtan transitional mudrocks and their equivalent strata Wujiaping Formation marine mudrocks in and around the eastern Sichuan Basin was investigated using field emission scanning electron microscopy(FE-SEM) and low-pressure N2 adsorption experiments. The results indicate that the Upper Permian mudrock is at a mature stage with total organic carbon(TOC) values ranging between 0.47% and 12.3%. The Longtan mudrocks mainly contain vitrinite, and their mineral composition is primarily clay. In contrast, the Wujiaping mudrocks are dominated by sapropelinite and solid bitumen, and their mineral compositions are mainly quartz and a notably high amount of pyrite. The FE-SEM reveals that clay mineral pores and microcracks are the common pore types in the Longtan mudrocks. The specific surface area and pore volume depend on the clay content but are negatively correlated with the TOC. The generation of nanometer pores in the Longtan mudrocks is caused by high clay mineral contents. Meanwhile,the Wujiaping mudrock mainly contains OM pores, and the pore parameters are positively correlated with the TOC. The OM pore development exhibits remarkable differences in the Longtan and Wujiaping mudrocks, which might be related to their sedimentary facies and maceral fractions. Vitrinite and inertinite appear as discrete particles in these mudrocks and cannot generate pores during thermal maturation. Sapropelinite often contains many secondary pores, and solid bitumen with large particles, usually with several pores, is not the major contributor to the pore system of the investigated mudrock.
Nanoscale pore characteristics of the Upper Permian Longtan transitional mudrocks and their equivalent strata Wujiaping Formation marine mudrocks in and around the eastern Sichuan Basin was investigated using field emission scanning electron microscopy(FE-SEM) and low-pressure N2 adsorption experiments. The results indicate that the Upper Permian mudrock is at a mature stage with total organic carbon(TOC) values ranging between 0.47% and 12.3%. The Longtan mudrocks mainly contain vitrinite, and their mineral composition is primarily clay. In contrast, the Wujiaping mudrocks are dominated by sapropelinite and solid bitumen, and their mineral compositions are mainly quartz and a notably high amount of pyrite. The FE-SEM reveals that clay mineral pores and microcracks are the common pore types in the Longtan mudrocks. The specific surface area and pore volume depend on the clay content but are negatively correlated with the TOC. The generation of nanometer pores in the Longtan mudrocks is caused by high clay mineral contents. Meanwhile,the Wujiaping mudrock mainly contains OM pores, and the pore parameters are positively correlated with the TOC. The OM pore development exhibits remarkable differences in the Longtan and Wujiaping mudrocks, which might be related to their sedimentary facies and maceral fractions. Vitrinite and inertinite appear as discrete particles in these mudrocks and cannot generate pores during thermal maturation. Sapropelinite often contains many secondary pores, and solid bitumen with large particles, usually with several pores, is not the major contributor to the pore system of the investigated mudrock.
Nanoscale pore characteristics of the Upper Permian Longtan transitional mudrocks and their equivalent strata Wujiaping Formation marine mudrocks in and around the eastern Sichuan Basin was investigated using field emission scanning electron microscopy(FE-SEM) and low-pressure N2 adsorption experiments. The results indicate that the Upper Permian mudrock is at a mature stage with total organic carbon(TOC) values ranging between 0.47% and 12.3%. The Longtan mudrocks mainly contain vitrinite, and their mineral composition is primarily clay. In contrast, the Wujiaping mudrocks are dominated by sapropelinite and solid bitumen, and their mineral compositions are mainly quartz and a notably high amount of pyrite. The FE-SEM reveals that clay mineral pores and microcracks are the common pore types in the Longtan mudrocks. The specific surface area and pore volume depend on the clay content but are negatively correlated with the TOC. The generation of nanometer pores in the Longtan mudrocks is caused by high clay mineral contents. Meanwhile,the Wujiaping mudrock mainly contains OM pores, and the pore parameters are positively correlated with the TOC. The OM pore development exhibits remarkable differences in the Longtan and Wujiaping mudrocks, which might be related to their sedimentary facies and maceral fractions. Vitrinite and inertinite appear as discrete particles in these mudrocks and cannot generate pores during thermal maturation. Sapropelinite often contains many secondary pores, and solid bitumen with large particles, usually with several pores, is not the major contributor to the pore system of the investigated mudrock.
引文
Ardakani,O.H.,Sanei,H.,Ghanizadeh,A.,Lavoie,D.,Chen,Z.H.,and Clarkson,C.R.,2018.Do all fractions of organic matter contribute equally in shale porosity?A case study from Upper Ordovician Utica Shale,southern Quebec,Canada.Marine and Petroleum Geology,92(4):794-808.
Borjigen,T.,Qin,J.Z.,Fu,X.D.,Yang,Y.F.,and Lu,L.F.,2014.Marine hydrocarbon source rocks of the Upper Permian Longtan Formation and their contribution to gas accumulation in the northeastern Sichuan Basin,southwest China.Marine and Petroleum Geology,57(11):160-172.
Brunauer,S., Deming,L.S.,Deming,W.E.,and Teller,E.,1940.On a theory of the van der Waals adsorption of gases.Journal of the American Chemical Society,62(7):1723-1732.
Cai J., 2017.Analysis on shale gas accumulation characteristics of the Permian Wujiaping Formation in western HubeiEastern Chongqing area.Petroleum Geology and Engineering,31(2):13-16(in Chinese with English abstract).
Cai,X.,Wang,L.,Jin.,Y.X.,Gao,Y.Q.,Cao,H,H.,and Ding.,A.X.,2016.Types and characteristics of.organic pore in shale gas reservoir of southeastern Chongqing area.Natural Gas Geoscience,27(3):513-519(in Chinese with English abstract).
Cao,T.T.,Song,Z.G.,Luo,H.Y.,Zhou,Y.Y.,and Wang,S.B.,2016.Pore system characteristics of Permian transitional shale reservoir in the Lower Yangtze region,China.Journal of Natural Gas Geosciences,1(5):383-395.
Cao,T.T.,Deng,M.,Song,Z.G.,Luo,H.Y.,and Hursthouse,A.S.,2018.Characteristics and controlling factors of pore structure of the Permian shale in southern Anhui province,China.Journal of Natural Gas Science and Engineering,60(12):228-245.
Chalmers,G.R.L.,and Bustin,R.M.,2007.The organic matter distribution and methane capacity of the Lower Cretaceous strata of northeastern British Columbia,Canada.International Journal of Coal Geology,70(1-3):223-239.
Chen,Q.,Zhang,J.C.,Tang,X.,Dang,W.,Li,Z.M.,Liu,C.,and Zhang,X.Z.,2016.Pore structure characterization of the Lower Permian marine-continental transitional black shale in the Southern North China Basin,Central China.Energy Fuels,30(12):10092-10105.
Curtis,J.B.,2002.Fractured shale-gas systems.AAPG Bulletin,86(11):1921-1938.
Curtis,M.E.,Ambrose,R.J.,and Songdergeld,C.H.,2010.Structural characterization of gas shales on the micro-and nano-scales.SPE 137693.
Curtis,M.E.,Cardott,B.J.,Sondergeld,C.H.,and Rai,C.H.,2012.Development of organic porosity in the Woodford Shale with increasing thermal maturity.International Journal of Coal Geology,103(12):26-31.
Dai,S.F.,Zou,J.H.,Jiang,Y.F.,Ward,C.R.,Wang,X.B.,Li,T.,Xue,W.F.,Liu,S.D.,Tian,H.M.,Sun.,X.H.,and Zhou,D.,2012.
Mineralogical and geochemical compositions of the Pennsylvanian coal in the Adaohai Mine,Daqingshan Coalfield,Inner Mongolia,China:modes of occurrence and origin of diaspore,gorceixite,and ammonian illite.International Journal of Coal Geology,94(5):250-270.Dang,W.,Zhang,J.C.,Tang,X.,Chen,Q.,Han,S.B.,Li,Z.M.,Du,X.R.,Wei,X.L.,Zhang,M.Q.,Liu,J.,Peng,J.L.,andHuang,Z.L.,2015.Shale gas potential of Lower Permian marine-continental transitional black shales in the Southern North China Basin,central China:Characterization of organic geochemistry.Journal of Natural Gas Science and Engineering,28(1):639-650.
Dong,T.,Harris,N.B.,Ayranci,K.,Twemlow,C.E.,and Nassichuk,B.R.,2015.Porosity characteristics of the Devonian Horn River shale,Canada:Insights from lithofacies classification and shale composition.International Journal of Coal Geology,141-142(3):74-90.
Fang,C.L.,Amro,M.,Jiang,G.S.,and Lu,H.Z.,2016.Laboratory studies of non-marine shale porosity characterization.Journal of Natural Gas Science and Engineering,33(7):1181-1 189.
Feng,G.X.,and Chen,S.J.,1988.Relationship between the reflectance of bitumen and vitrinite in rock.Natural Gas Industry,8(3):20-24(in Chinese with English abstract).Fishman.,N.S.,Hackley,P.C.,Lowers,H.A.,Hill,R.J.,Egnehoff,S.O.,Eberl,D.S.,and Blum,A.E.,2012.The nature of porosity in organic-rich mudstones of the Upper Jurassic Kimmeridge Clay Formation,North Sea,offshore United Kingdom.International Journal of Coal Geology,103(12):32-50.
Gao,J.,Liu,G.D.,Yang,W.W.,Zhao,D.R.,Chen,W.,and Liu,L.,2016.Geological and geochemical characterization of lacustrine shale,a case study of Lower Jurassic Badaowan shale in the Junggar Basin,Northwest China.Journal of Natural Gas Science and Engineering,31(4):15-27.
Guo,T.L.,2013.Evaluation of highly thermally mature shalegas reservoirs in complex structural parts of the Sichuan Basin.Journal of Earth Science,24(6):863-873.
Guo,T.L.,and Zhang,H.R.,2014.Formation and enrichment mode of Jiaoshiba shale gas field,Sichuan Basin.Petroleum Exploration and Development,41(1):31-40.
Guo,X.S.,Hu,D.F.,Liu,R.B.,Wei,X.F.,and Wei,F.B.,2018.Geological conditions and exploration potential of Permian marine-continent transitional facies shale gas in the Sichuan Basin.Natural Gas Industry,38(10):11-18(in Chinese with English abstract).
Han,K.,Ju,Y.W.,Wang,G.C.,Bao,S.J.,Bu,H.L.,and Neupane,B.,2016.Shale composition and pore structure variations in the progradation direction:A case study of transitional shales in the Xu-Huai district,southern North China.Journal of Natural Gas Science and Engineering,36(11):1178-1187.
Hu,J.G.,Tang,S.H.,and Zhang,S.H.,2016.Investigation of pore structure and fractal characteristics of the Lower Silurian Longmaxi Shales in western Hunan and Hubei Provinces in China.Journal of Natural Gas Science and Engineering,28(1):522-535.
Jiang,S.,Xu,Z.Y.,Feng,Y.L.,Zhang,J.C.,Cai,D.S.,Chen,L.,Wu,Y.,Zhou,D.S.,Bao,S.J.,and Long,S.X.,2016.
Geological characteristics of hydrocarbon-bearing marine,transitional and lacustrine shales in China.Journal of Asian Earth Sciences,115(1):404-418.
Ko,L.T.,Ruppel,S.C.,Loucks,R.G.,Hackley,P.C.,Zhang,T.W.,and Shao,D.Y.,2018.Pore-types and pore-network evolution in Upper Devonian-Lower Mississippian Woodford and Mississippian Barnett mudstones:Insights from laboratory thermal maturation and organic petrology.International Journal of Coal Geology,190(4):3-28.
Li A,Ding WL,He JH,Dai,P.,Yin,S.,and Xie,F.,2016.Investigation of pore structure and fractal characteristics of organic-rich shale reservoirs:A case study of Lower Cambrian Qingzhusi formation in Malong block of eastern Yunan Province,South China.Marine and Petroleum Geology,70(2):46-57.
Li,J.J.,Yin,J.X.,Zhang,Y.N.,Lu,S.F.,Wang,W.M.,Li,J.B.,Chen,F.W.,and Meng,Y.L.,2015.A comparison of experimental methods for describing shale pore features-A case study in the Bohai Bay Basin of eastern China.International Journal of Coal Geology,152(12):39-49.
Liang,L.X.,Xiong,J.,Liu,and X.J.,2015.An investigation of the fractal characteristics of the Upper Ordovician Wufeng Formation shale using nitrogen adsorption analysis.Journal ofNatural Gas Science and Engineering,27(11):402-409.
Lin,L.B.,Yu,Y.,Zhai,C.B.,Li,Y.H.,Wang,Y.N.,Liu,G.X.,Guo,Y.,and Gao,J.,2018.Paleogeography and shale development characteristics of the Later Permian Longtan Formation in southeastern Sichuan Basin,China.Marine and Petroleum Geology,95(8):67-81.
Liu.,B.,Schieber,J.,and Mastalcrz,M.,2017.Combined SEM and reflected petrography of organic matter in the New Albany(Devonian-Mississippian)in the Illinois Basin:A perspective on organic pore development with thermal maturation.International Journal of Coal Geology,184(11):57-72.
Liu,G.X.,Jin,Z.J.,Deng,M.,Zhai,C.B.,and Guan,H.L.,2015.Exploration potential for shale gas in the Upper Permian Longtan Formation in eastern Sichuan Basin.Oil and Gas Geology,36(3):481-487(in Chinese with English abstract).Liu,M.,2016.Upper Paleozoic shale gas reservoiring features and resource porential assessment in Qinshui Basin.Coal Geology of China,28(12):25-33(in Chinese with English abstract).
Liu,X.J.,Xiong,J.,and Liang,L.X.,2015.Investigation of pore structure and fractal characteristics of organic-rich Yangchang formation shale in central China by nitrogen adsorption/desorption analysis.Journal of Natural Gas Science and Engineering,22(7):62-72.
Loucks R.G.,Reed R.M.,Ruppel S.C.,and Jarvie,D.M.,2009.Morphology,genesis,and distribution of nanometer-scale pores in siliceous mudstones of the Mississippian Barnett shale.Journal of Sedimentary Research,79(12):848-861.Loucks,R.G.,Reed,R.M.,Ruppel,S.C.,and Hammes,U.,2012.Spectrum of pore types and networks in mudrocks and a descriptive classification for matrix-related mudrock pores.AAPG Bulletin,96(6):1071-1098.
Luo,W.,Hou,M.C.,Liu,X.C.,Huang,S.G.,Chao,H.,Zhang,R.,and Deng,X.,2018.Geological and geochemical characteristics of marine-continental transitional shale from the Upper Permian Longtan formation.,Northwestern Guizhou,China.Marine and Petroleum Geology,89(1):58-67.
Mastalerz,M.,Schimmelmann,A.,Drobniak,A.,and Chen,Y.Y.,2013.Porosity of Devonian and Mississippian New Albany Shale across a maturation gradient:insights from organicpetrology,gas adsorption,and mercury intrusion.AAPG Bulletin,97(10):1621-1643.
Mathia,E.J.,Bowen,L.,Thomas,K.M.,and Aplin,A.C.,2016.Evoluation of porosity and pore types in organic-rich,calcareous,Lower Toarcian Posidonia Shale.Marine and Petroleum Geology,75(8):117-139
Nie,H.K.,and Zhang,J.C.,2012.Shale gas accumulation conditions and gas content calculation:A case study of Sichuan Basin and its periphery in the Lower Paleozoic.Acta Geological Sinica,86(2):349-361(in Chinese with English abstract).
Nie,H.K.,Jin,Z.J.,and Zhang,J.C.,2018.Characteristics of three organic matter pore types in the Wufeng-Longmaxi shale of the Sichuan Basin,Southwest China.Scientific Reports,8(1):1-11.
Pan,L.,Xiao,X.M.,Tian,H.,Zhou,Q.,Chen,J.,Li,T.F.,and 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.International Journal of Coal Geology,146(7):68-78.Peng,B.,Liu,Y.S.,Qi.,F.C.,Dong,Y.,and Wang,Z.Y.,2017.
Study on the accumulation conditions of shale gas in Doushantuo Formation in Western Hubei.Geological Review,63(5):1293-1306(in Chinese with English abstract).
Ross,D.J.K.,and Bustin,R.M.,2009.The importance of shale composition and pore structure upon gas storage potential of shale gas reservoirs.Marine and Petroleum Geology,26(6):916-927.
Sun,M.D.,Yu,B.S.,Hu,Q.H.,Chen,S.,Xia,W.,and Ye,R.C.,2016.Nanoscale pore characteristics of the Lower Cambrian Niutitang Formation Shale:A case study from Well Yuke#1in the Southeast of Chongqing,China.International Journal of Coal Geology,154-155(1):16-29.
Sun,Z.P.,Wang,Y.L.,Wei,Z.F.,Zhang,M.F.,Wang,G.,Wang,Z.X.,Zhuo,S.G.,and Xu,L.,2017.Shale gas content and geochemical characteristics of marine-continental transitional shale:A case from the Shanxi formation of Ordos basin.Journal of China University of Mining and Technology,46(4):673-682(in Chinese with English abstract).
Tang,X.,Zhang,J.C.,Wang,X.Z.,Yu,B.S.,Ding,W.L.,Xiong,J.Y.,Yang,Y.T.,Wang,L.,and Yang,C., 2014.Shale characteristics in the southeastern Ordos Basin,China:Implications for hydrocarbon accumulation conditions and the potential of continental shales.International Journal of Coal Geology,128-129(8):32-46.
Tang,X.,Zhang,J.C.,Dang,W.,Yu,B.S.,Ma,L.,Yang,Y.T.,Chen,H,Y.,Huang,H.,and Zhao,P.W.,2016.The reservoir property of the Upper Paleozoic marine-continental transitional shale and its gas-bearing capacity in the Southeastern Ordos Basin.Earth Science Frontiers,23(2):147-157(in Chinese with English abstract).
Tang,X.L.,Jiang,Z.X.,Li,Z.,Gao,Y.Z.,Bai,Y.Q.,Zhao,S.,and Feng,J.,2015.The effect of the variation in material composition on the heterogeneous pore structure of highmaturity shale of the Silurian Longmaxi formaton in the southeastern Sichuan Basin,China.Journal of Natural Gas Science and Engineering,23(3):464-473.
Tang,X.L.,Jiang,Z.X.,Huang,H,X.,Jiang,S.,Yang,L.,Xiong,F.Y.,Chen,L.,and Feng,J.,2016.Lithofacies characteristics and its effect on gas storage of the Silurian Longmaxi marine shale in the southeast Sichuan Basin,China,Journal of Natural Gas Science and Engineering,28(1):338-346.
Tian.,H.,Pan,L.,Xiao,X.M.,Wilkins,R.W.T.,Meng,Z.P.,and Huang,B.J.,2013.A preliminary study on the pore characterization of Lower Silurian black shales in the Chuandong Thrust Fold Belt,southwestern China using low pressure N2 adsorption and FE-SEM methods.Marine and Petroleum Geology,48(12):8-19.
Tian,Z.B.,Wei,S.H.,Wang,J.Q.,Li,L.Y.,Tang,S.H.,and Li,J.,2017.Characteristics of micro-scale pore structures of marine-continental transitional shale from the mid-eastern area,Qinshui Basin.Journal of China Coal Society,42(7):1818-1827(in Chinese with English abstract).
Wang,Y.,Chen J.,Hu L.,and Zhu Y.M.,2013.Sedimentary environment control on shale gas reservoir:A case study of Lower Cambrian Qingzhusi Formation in the Middle Lower Yangtze area.Journal of China Coal Society,38(5):845-850(in Chinese with English abstract).
Wang,R.Y.,Gu,Y.,Ding,W.L.,Gong,D.J.,Yin,S.,Wang,X.H.,Zhou,X.H.,Li,A.,Xiao,Z.K.,and Gui,Z.X.,2016.Characteristics and dominant controlling factors of organicrich marine shales with high thermal maturity:A case study of the Lower Cambrian Niutitang Formation in the Cen'gong block,southern China.Journal of Natural Gas Science and Engineering,33(7):81-96.
Wei,M.M.,Zhang,L.,Xiong,X.Y.,Li,J.H.,and Peng,P.A.,2016.Nanopore structure characterization for organic-rich shale using the non-local-density functional theory by a combination of N2 and CO2 adsorption.Microporous and Mesoporous Materials,227(6):88-94.
Xi,Z.D.,Tang,S.H.,Zhang,S.H.,and Li, J.,2017a.Nano-scale pore structure of marine-continental transitional shale from liulin area,the Eastern Margin of Ordos Basin,China.Journal of Nanoscience and Nanotechnology,17(9):6109-6123.
Xi,Z.D.,Tang,S.H.,Zhang,S.H.,and Sun,K.,2017b.Pore structure characteristics of marine continental transitional shale:a case study in the Qinshui Basin,China.Energy Fuels,31(8):7854-7866.
Xiong,J.,Liu, X.J.,and Liang,X,X.,2015.Experimental study on the pore structure characteristics of the Upper Ordovician Wufeng Formation shale in the southwest portion of the Sichuan Basin,China.Journal of Natural Gas Science and Engineering,22(1):530-539.
Yang,C.,Zhang,J.C.,Han,S.B.,Xue,B.,and Zhao,Q.R.,2016.Classification and the Development regularity of organicassociated pores(OAP)through a comparative study of marine,transitional,and terrestrial shales in China.Journal of Natural Gas Science and Engineering,36(11):358-368.
Yang,C.,Zhang,J.C.,Tang,X.,Ding,J.H.,Zhao,Q.R.,Dang,W.,Chen,H.Y.,Su,Y.,Li,B.W.,and Lu,D.F.,2017a.Comparative study on micro-pore structure of marine,terrestrial,and transitional shales in key areas,China.International Journal of Coal Geology,71(2):76-92.
Yang,C.,Zhang,J.C.,Wang,X.Z.,Tang,X.,Chen,Y.C.,Jiang,L.L.,and Gong,X.,2017b.Nanoscale pore structure and fractal characteristics of a marine-continental transitional shale:A case study from the lower Permian Shanxi Shale in the southeastern Ordos Basin,China.Marine and Petroleum Geology,88(12):54-68.
Zhang,H.R.,2016.Gas content of the Silurian shale in the SE Sichuan Basin and its controlling factos.Natural Gas Industry,36(8):36-42(in Chinese with English abstract).
Zhang,J.Z.,Li,X.Q.,Wei,Q.,Sun,K.X.,Zhang,G.W.,and Wang,F.Y.,2017a.Characterization of full-sized pore structure and fractal characteristics of marine-continental transitional Longtan Formation shale of Sichuan Basin,South China.Energy Fuels,31(10):10490-10504.
Zhang,M.C.,Feng,H.,Weng,J.C.,Wang,K.,Qiu,Q.L.,and Liu,Y.J,2018.Reservoir characteristics and gas-bearing potential of transitional-facies shale,Henan province.Natural Gas Exploration and Development,41(2):37-47(in Chinese with English abstract).
Zhang,Q.,Pang,Z.L.,Zhang,J.C.,Lin,W.,and Jiang,S.,2017b.Qualitative and quantitative characterization of a transitional shale reservoir:A case study from the Upper Carboniferous Taiyuan shale in the eastern uplift of Liaohe Depression,China.Marine and Petroleum Geology,80(2):307-320.
Zhang,T.W.,Ellis,G.S.,Ruppel,S.C.,Milliken,K.,and Yang,S.,2012.Effect of organic-matter type and thermal maturity on methane adsorption in shale-gas systems.Organic Geochemistry,47(6):120-131.
Zhou,S.W.,Yan,G.,Xue,Q.H..,Guo,W.,and Li,X.B.,2016.2D and 3D nanopore characterization of gas shale in Longmaxi formation based on FIB-SEM.Marine and Petroleum Geology,73(5):174-180.
Borjigen,T.,Qin,J.Z.,Fu,X.D.,Yang,Y.F.,and Lu,L.F.,2014.Marine hydrocarbon source rocks of the Upper Permian Longtan Formation and their contribution to gas accumulation in the northeastern Sichuan Basin,southwest China.Marine and Petroleum Geology,57(11):160-172.
Brunauer,S., Deming,L.S.,Deming,W.E.,and Teller,E.,1940.On a theory of the van der Waals adsorption of gases.Journal of the American Chemical Society,62(7):1723-1732.
Cai J., 2017.Analysis on shale gas accumulation characteristics of the Permian Wujiaping Formation in western HubeiEastern Chongqing area.Petroleum Geology and Engineering,31(2):13-16(in Chinese with English abstract).
Cai,X.,Wang,L.,Jin.,Y.X.,Gao,Y.Q.,Cao,H,H.,and Ding.,A.X.,2016.Types and characteristics of.organic pore in shale gas reservoir of southeastern Chongqing area.Natural Gas Geoscience,27(3):513-519(in Chinese with English abstract).
Cao,T.T.,Song,Z.G.,Luo,H.Y.,Zhou,Y.Y.,and Wang,S.B.,2016.Pore system characteristics of Permian transitional shale reservoir in the Lower Yangtze region,China.Journal of Natural Gas Geosciences,1(5):383-395.
Cao,T.T.,Deng,M.,Song,Z.G.,Luo,H.Y.,and Hursthouse,A.S.,2018.Characteristics and controlling factors of pore structure of the Permian shale in southern Anhui province,China.Journal of Natural Gas Science and Engineering,60(12):228-245.
Chalmers,G.R.L.,and Bustin,R.M.,2007.The organic matter distribution and methane capacity of the Lower Cretaceous strata of northeastern British Columbia,Canada.International Journal of Coal Geology,70(1-3):223-239.
Chen,Q.,Zhang,J.C.,Tang,X.,Dang,W.,Li,Z.M.,Liu,C.,and Zhang,X.Z.,2016.Pore structure characterization of the Lower Permian marine-continental transitional black shale in the Southern North China Basin,Central China.Energy Fuels,30(12):10092-10105.
Curtis,J.B.,2002.Fractured shale-gas systems.AAPG Bulletin,86(11):1921-1938.
Curtis,M.E.,Ambrose,R.J.,and Songdergeld,C.H.,2010.Structural characterization of gas shales on the micro-and nano-scales.SPE 137693.
Curtis,M.E.,Cardott,B.J.,Sondergeld,C.H.,and Rai,C.H.,2012.Development of organic porosity in the Woodford Shale with increasing thermal maturity.International Journal of Coal Geology,103(12):26-31.
Dai,S.F.,Zou,J.H.,Jiang,Y.F.,Ward,C.R.,Wang,X.B.,Li,T.,Xue,W.F.,Liu,S.D.,Tian,H.M.,Sun.,X.H.,and Zhou,D.,2012.
Mineralogical and geochemical compositions of the Pennsylvanian coal in the Adaohai Mine,Daqingshan Coalfield,Inner Mongolia,China:modes of occurrence and origin of diaspore,gorceixite,and ammonian illite.International Journal of Coal Geology,94(5):250-270.Dang,W.,Zhang,J.C.,Tang,X.,Chen,Q.,Han,S.B.,Li,Z.M.,Du,X.R.,Wei,X.L.,Zhang,M.Q.,Liu,J.,Peng,J.L.,andHuang,Z.L.,2015.Shale gas potential of Lower Permian marine-continental transitional black shales in the Southern North China Basin,central China:Characterization of organic geochemistry.Journal of Natural Gas Science and Engineering,28(1):639-650.
Dong,T.,Harris,N.B.,Ayranci,K.,Twemlow,C.E.,and Nassichuk,B.R.,2015.Porosity characteristics of the Devonian Horn River shale,Canada:Insights from lithofacies classification and shale composition.International Journal of Coal Geology,141-142(3):74-90.
Fang,C.L.,Amro,M.,Jiang,G.S.,and Lu,H.Z.,2016.Laboratory studies of non-marine shale porosity characterization.Journal of Natural Gas Science and Engineering,33(7):1181-1 189.
Feng,G.X.,and Chen,S.J.,1988.Relationship between the reflectance of bitumen and vitrinite in rock.Natural Gas Industry,8(3):20-24(in Chinese with English abstract).Fishman.,N.S.,Hackley,P.C.,Lowers,H.A.,Hill,R.J.,Egnehoff,S.O.,Eberl,D.S.,and Blum,A.E.,2012.The nature of porosity in organic-rich mudstones of the Upper Jurassic Kimmeridge Clay Formation,North Sea,offshore United Kingdom.International Journal of Coal Geology,103(12):32-50.
Gao,J.,Liu,G.D.,Yang,W.W.,Zhao,D.R.,Chen,W.,and Liu,L.,2016.Geological and geochemical characterization of lacustrine shale,a case study of Lower Jurassic Badaowan shale in the Junggar Basin,Northwest China.Journal of Natural Gas Science and Engineering,31(4):15-27.
Guo,T.L.,2013.Evaluation of highly thermally mature shalegas reservoirs in complex structural parts of the Sichuan Basin.Journal of Earth Science,24(6):863-873.
Guo,T.L.,and Zhang,H.R.,2014.Formation and enrichment mode of Jiaoshiba shale gas field,Sichuan Basin.Petroleum Exploration and Development,41(1):31-40.
Guo,X.S.,Hu,D.F.,Liu,R.B.,Wei,X.F.,and Wei,F.B.,2018.Geological conditions and exploration potential of Permian marine-continent transitional facies shale gas in the Sichuan Basin.Natural Gas Industry,38(10):11-18(in Chinese with English abstract).
Han,K.,Ju,Y.W.,Wang,G.C.,Bao,S.J.,Bu,H.L.,and Neupane,B.,2016.Shale composition and pore structure variations in the progradation direction:A case study of transitional shales in the Xu-Huai district,southern North China.Journal of Natural Gas Science and Engineering,36(11):1178-1187.
Hu,J.G.,Tang,S.H.,and Zhang,S.H.,2016.Investigation of pore structure and fractal characteristics of the Lower Silurian Longmaxi Shales in western Hunan and Hubei Provinces in China.Journal of Natural Gas Science and Engineering,28(1):522-535.
Jiang,S.,Xu,Z.Y.,Feng,Y.L.,Zhang,J.C.,Cai,D.S.,Chen,L.,Wu,Y.,Zhou,D.S.,Bao,S.J.,and Long,S.X.,2016.
Geological characteristics of hydrocarbon-bearing marine,transitional and lacustrine shales in China.Journal of Asian Earth Sciences,115(1):404-418.
Ko,L.T.,Ruppel,S.C.,Loucks,R.G.,Hackley,P.C.,Zhang,T.W.,and Shao,D.Y.,2018.Pore-types and pore-network evolution in Upper Devonian-Lower Mississippian Woodford and Mississippian Barnett mudstones:Insights from laboratory thermal maturation and organic petrology.International Journal of Coal Geology,190(4):3-28.
Li A,Ding WL,He JH,Dai,P.,Yin,S.,and Xie,F.,2016.Investigation of pore structure and fractal characteristics of organic-rich shale reservoirs:A case study of Lower Cambrian Qingzhusi formation in Malong block of eastern Yunan Province,South China.Marine and Petroleum Geology,70(2):46-57.
Li,J.J.,Yin,J.X.,Zhang,Y.N.,Lu,S.F.,Wang,W.M.,Li,J.B.,Chen,F.W.,and Meng,Y.L.,2015.A comparison of experimental methods for describing shale pore features-A case study in the Bohai Bay Basin of eastern China.International Journal of Coal Geology,152(12):39-49.
Liang,L.X.,Xiong,J.,Liu,and X.J.,2015.An investigation of the fractal characteristics of the Upper Ordovician Wufeng Formation shale using nitrogen adsorption analysis.Journal ofNatural Gas Science and Engineering,27(11):402-409.
Lin,L.B.,Yu,Y.,Zhai,C.B.,Li,Y.H.,Wang,Y.N.,Liu,G.X.,Guo,Y.,and Gao,J.,2018.Paleogeography and shale development characteristics of the Later Permian Longtan Formation in southeastern Sichuan Basin,China.Marine and Petroleum Geology,95(8):67-81.
Liu.,B.,Schieber,J.,and Mastalcrz,M.,2017.Combined SEM and reflected petrography of organic matter in the New Albany(Devonian-Mississippian)in the Illinois Basin:A perspective on organic pore development with thermal maturation.International Journal of Coal Geology,184(11):57-72.
Liu,G.X.,Jin,Z.J.,Deng,M.,Zhai,C.B.,and Guan,H.L.,2015.Exploration potential for shale gas in the Upper Permian Longtan Formation in eastern Sichuan Basin.Oil and Gas Geology,36(3):481-487(in Chinese with English abstract).Liu,M.,2016.Upper Paleozoic shale gas reservoiring features and resource porential assessment in Qinshui Basin.Coal Geology of China,28(12):25-33(in Chinese with English abstract).
Liu,X.J.,Xiong,J.,and Liang,L.X.,2015.Investigation of pore structure and fractal characteristics of organic-rich Yangchang formation shale in central China by nitrogen adsorption/desorption analysis.Journal of Natural Gas Science and Engineering,22(7):62-72.
Loucks R.G.,Reed R.M.,Ruppel S.C.,and Jarvie,D.M.,2009.Morphology,genesis,and distribution of nanometer-scale pores in siliceous mudstones of the Mississippian Barnett shale.Journal of Sedimentary Research,79(12):848-861.Loucks,R.G.,Reed,R.M.,Ruppel,S.C.,and Hammes,U.,2012.Spectrum of pore types and networks in mudrocks and a descriptive classification for matrix-related mudrock pores.AAPG Bulletin,96(6):1071-1098.
Luo,W.,Hou,M.C.,Liu,X.C.,Huang,S.G.,Chao,H.,Zhang,R.,and Deng,X.,2018.Geological and geochemical characteristics of marine-continental transitional shale from the Upper Permian Longtan formation.,Northwestern Guizhou,China.Marine and Petroleum Geology,89(1):58-67.
Mastalerz,M.,Schimmelmann,A.,Drobniak,A.,and Chen,Y.Y.,2013.Porosity of Devonian and Mississippian New Albany Shale across a maturation gradient:insights from organicpetrology,gas adsorption,and mercury intrusion.AAPG Bulletin,97(10):1621-1643.
Mathia,E.J.,Bowen,L.,Thomas,K.M.,and Aplin,A.C.,2016.Evoluation of porosity and pore types in organic-rich,calcareous,Lower Toarcian Posidonia Shale.Marine and Petroleum Geology,75(8):117-139
Nie,H.K.,and Zhang,J.C.,2012.Shale gas accumulation conditions and gas content calculation:A case study of Sichuan Basin and its periphery in the Lower Paleozoic.Acta Geological Sinica,86(2):349-361(in Chinese with English abstract).
Nie,H.K.,Jin,Z.J.,and Zhang,J.C.,2018.Characteristics of three organic matter pore types in the Wufeng-Longmaxi shale of the Sichuan Basin,Southwest China.Scientific Reports,8(1):1-11.
Pan,L.,Xiao,X.M.,Tian,H.,Zhou,Q.,Chen,J.,Li,T.F.,and 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.International Journal of Coal Geology,146(7):68-78.Peng,B.,Liu,Y.S.,Qi.,F.C.,Dong,Y.,and Wang,Z.Y.,2017.
Study on the accumulation conditions of shale gas in Doushantuo Formation in Western Hubei.Geological Review,63(5):1293-1306(in Chinese with English abstract).
Ross,D.J.K.,and Bustin,R.M.,2009.The importance of shale composition and pore structure upon gas storage potential of shale gas reservoirs.Marine and Petroleum Geology,26(6):916-927.
Sun,M.D.,Yu,B.S.,Hu,Q.H.,Chen,S.,Xia,W.,and Ye,R.C.,2016.Nanoscale pore characteristics of the Lower Cambrian Niutitang Formation Shale:A case study from Well Yuke#1in the Southeast of Chongqing,China.International Journal of Coal Geology,154-155(1):16-29.
Sun,Z.P.,Wang,Y.L.,Wei,Z.F.,Zhang,M.F.,Wang,G.,Wang,Z.X.,Zhuo,S.G.,and Xu,L.,2017.Shale gas content and geochemical characteristics of marine-continental transitional shale:A case from the Shanxi formation of Ordos basin.Journal of China University of Mining and Technology,46(4):673-682(in Chinese with English abstract).
Tang,X.,Zhang,J.C.,Wang,X.Z.,Yu,B.S.,Ding,W.L.,Xiong,J.Y.,Yang,Y.T.,Wang,L.,and Yang,C., 2014.Shale characteristics in the southeastern Ordos Basin,China:Implications for hydrocarbon accumulation conditions and the potential of continental shales.International Journal of Coal Geology,128-129(8):32-46.
Tang,X.,Zhang,J.C.,Dang,W.,Yu,B.S.,Ma,L.,Yang,Y.T.,Chen,H,Y.,Huang,H.,and Zhao,P.W.,2016.The reservoir property of the Upper Paleozoic marine-continental transitional shale and its gas-bearing capacity in the Southeastern Ordos Basin.Earth Science Frontiers,23(2):147-157(in Chinese with English abstract).
Tang,X.L.,Jiang,Z.X.,Li,Z.,Gao,Y.Z.,Bai,Y.Q.,Zhao,S.,and Feng,J.,2015.The effect of the variation in material composition on the heterogeneous pore structure of highmaturity shale of the Silurian Longmaxi formaton in the southeastern Sichuan Basin,China.Journal of Natural Gas Science and Engineering,23(3):464-473.
Tang,X.L.,Jiang,Z.X.,Huang,H,X.,Jiang,S.,Yang,L.,Xiong,F.Y.,Chen,L.,and Feng,J.,2016.Lithofacies characteristics and its effect on gas storage of the Silurian Longmaxi marine shale in the southeast Sichuan Basin,China,Journal of Natural Gas Science and Engineering,28(1):338-346.
Tian.,H.,Pan,L.,Xiao,X.M.,Wilkins,R.W.T.,Meng,Z.P.,and Huang,B.J.,2013.A preliminary study on the pore characterization of Lower Silurian black shales in the Chuandong Thrust Fold Belt,southwestern China using low pressure N2 adsorption and FE-SEM methods.Marine and Petroleum Geology,48(12):8-19.
Tian,Z.B.,Wei,S.H.,Wang,J.Q.,Li,L.Y.,Tang,S.H.,and Li,J.,2017.Characteristics of micro-scale pore structures of marine-continental transitional shale from the mid-eastern area,Qinshui Basin.Journal of China Coal Society,42(7):1818-1827(in Chinese with English abstract).
Wang,Y.,Chen J.,Hu L.,and Zhu Y.M.,2013.Sedimentary environment control on shale gas reservoir:A case study of Lower Cambrian Qingzhusi Formation in the Middle Lower Yangtze area.Journal of China Coal Society,38(5):845-850(in Chinese with English abstract).
Wang,R.Y.,Gu,Y.,Ding,W.L.,Gong,D.J.,Yin,S.,Wang,X.H.,Zhou,X.H.,Li,A.,Xiao,Z.K.,and Gui,Z.X.,2016.Characteristics and dominant controlling factors of organicrich marine shales with high thermal maturity:A case study of the Lower Cambrian Niutitang Formation in the Cen'gong block,southern China.Journal of Natural Gas Science and Engineering,33(7):81-96.
Wei,M.M.,Zhang,L.,Xiong,X.Y.,Li,J.H.,and Peng,P.A.,2016.Nanopore structure characterization for organic-rich shale using the non-local-density functional theory by a combination of N2 and CO2 adsorption.Microporous and Mesoporous Materials,227(6):88-94.
Xi,Z.D.,Tang,S.H.,Zhang,S.H.,and Li, J.,2017a.Nano-scale pore structure of marine-continental transitional shale from liulin area,the Eastern Margin of Ordos Basin,China.Journal of Nanoscience and Nanotechnology,17(9):6109-6123.
Xi,Z.D.,Tang,S.H.,Zhang,S.H.,and Sun,K.,2017b.Pore structure characteristics of marine continental transitional shale:a case study in the Qinshui Basin,China.Energy Fuels,31(8):7854-7866.
Xiong,J.,Liu, X.J.,and Liang,X,X.,2015.Experimental study on the pore structure characteristics of the Upper Ordovician Wufeng Formation shale in the southwest portion of the Sichuan Basin,China.Journal of Natural Gas Science and Engineering,22(1):530-539.
Yang,C.,Zhang,J.C.,Han,S.B.,Xue,B.,and Zhao,Q.R.,2016.Classification and the Development regularity of organicassociated pores(OAP)through a comparative study of marine,transitional,and terrestrial shales in China.Journal of Natural Gas Science and Engineering,36(11):358-368.
Yang,C.,Zhang,J.C.,Tang,X.,Ding,J.H.,Zhao,Q.R.,Dang,W.,Chen,H.Y.,Su,Y.,Li,B.W.,and Lu,D.F.,2017a.Comparative study on micro-pore structure of marine,terrestrial,and transitional shales in key areas,China.International Journal of Coal Geology,71(2):76-92.
Yang,C.,Zhang,J.C.,Wang,X.Z.,Tang,X.,Chen,Y.C.,Jiang,L.L.,and Gong,X.,2017b.Nanoscale pore structure and fractal characteristics of a marine-continental transitional shale:A case study from the lower Permian Shanxi Shale in the southeastern Ordos Basin,China.Marine and Petroleum Geology,88(12):54-68.
Zhang,H.R.,2016.Gas content of the Silurian shale in the SE Sichuan Basin and its controlling factos.Natural Gas Industry,36(8):36-42(in Chinese with English abstract).
Zhang,J.Z.,Li,X.Q.,Wei,Q.,Sun,K.X.,Zhang,G.W.,and Wang,F.Y.,2017a.Characterization of full-sized pore structure and fractal characteristics of marine-continental transitional Longtan Formation shale of Sichuan Basin,South China.Energy Fuels,31(10):10490-10504.
Zhang,M.C.,Feng,H.,Weng,J.C.,Wang,K.,Qiu,Q.L.,and Liu,Y.J,2018.Reservoir characteristics and gas-bearing potential of transitional-facies shale,Henan province.Natural Gas Exploration and Development,41(2):37-47(in Chinese with English abstract).
Zhang,Q.,Pang,Z.L.,Zhang,J.C.,Lin,W.,and Jiang,S.,2017b.Qualitative and quantitative characterization of a transitional shale reservoir:A case study from the Upper Carboniferous Taiyuan shale in the eastern uplift of Liaohe Depression,China.Marine and Petroleum Geology,80(2):307-320.
Zhang,T.W.,Ellis,G.S.,Ruppel,S.C.,Milliken,K.,and Yang,S.,2012.Effect of organic-matter type and thermal maturity on methane adsorption in shale-gas systems.Organic Geochemistry,47(6):120-131.
Zhou,S.W.,Yan,G.,Xue,Q.H..,Guo,W.,and Li,X.B.,2016.2D and 3D nanopore characterization of gas shale in Longmaxi formation based on FIB-SEM.Marine and Petroleum Geology,73(5):174-180.