The North Carnarvon Basin, which lies in the North West Shelf of Australia, is highly rich in gas resources. As a typical passive marginal basin, it experienced the pre-rifting, early rifting, main rifting, late rifti...The North Carnarvon Basin, which lies in the North West Shelf of Australia, is highly rich in gas resources. As a typical passive marginal basin, it experienced the pre-rifting, early rifting, main rifting, late rifting, post-rifting sagging and passive margin stages. The basin was mainly filled with thick Mesozoic-Cenozoic sediments, of which the Mesozoic hosts the principal source, reservoir and seal intervals. Mesozoic palaeogeography has an important control on the oil and gas distribution. Triassic gas-prone source rocks of deltaic origin deter-mine the high endowment of natural gases in the North Carnarvon Basin. The more restricted distribution of oil accumulations is controlled by oil source rocks in the Upper Jurassic Dingo Claystone. The Muderong Shale deposited in the Early Cretaceous marine transgression provides the effective regional seal for the underlying oil and gas reservoirs.展开更多
The lithofacies palaeogeography of the Late Permian Wujiaping Age in Middle and Upper Yangtze Region was studied based on petrography and the ＂single factor analysis and multifactor comprehensive mapping＂ method. Th...The lithofacies palaeogeography of the Late Permian Wujiaping Age in Middle and Upper Yangtze Region was studied based on petrography and the ＂single factor analysis and multifactor comprehensive mapping＂ method. The Upper Permian Wujiaping Stage in the Middle and Upper Yangtze Region is mainly composed of carbonate rocks and clastic rocks, with lesser amounts of siliceous rocks, pyroclastic rocks, volcanic rocks and coal. The rocks can be divided into three types, including clastic rock, clastic rock-limestone and limestone-siliceous rock, and four fundamental ecological types and four fossil assemblages are recognized in the Wujiaping Stage. Based on a petrological and palaeoecological study, six single factors were selected, namely, thickness （m）, content （%） of marine rocks, content （%） of shallow water carbonate rocks, content （%） of biograins with limemud, content （%） of thinbedded siliceous rocks and content （%） of deep water sedimentary rocks. Six single factors maps of the Wujiaping Stage and one lithofacies palaeogeography map of the Wujiaping Age were composed. Palaeogeographic units from west to east include an eroded area, an alluvial plain, a clastic rock platform, a carbonate rock platform where biocrowds developed, a slope and a basin. In addition, a clastic rock platform exists in the southeast of the study area. Hydro- carbon source rock and reservoir conditions were preliminarily analyzed based on lithofacies palaeogeography. Sedimentary environments have obvious controls over the development of the resource rocks. With regard to the abundance of organic matter, the hydrocarbon potential of the coastal swamp environment is the best, followed by the basin environment and the carbonate rock platform. The gas reservoir types of the Wujiaping Stage can be classified as conventional and unconventional gas reservoirs, like coal bed gas and shale gas; all of them have well exploration prospects.展开更多
Based on the petrological study,according to single factor analysis and multifactor comprehensive mapping method,the quantitative lithofacies palaeogeography of the Upper Permian Changxing Stage of the Middle and Uppe...Based on the petrological study,according to single factor analysis and multifactor comprehensive mapping method,the quantitative lithofacies palaeogeography of the Upper Permian Changxing Stage of the Middle and Upper Yangtze Region was studied.The Changxing Stage in the Middle and Upper Yangtze Region is mainly composed of carbonate rocks;in addition,clastic and siliceous rocks occur with rare coals and pyroclastic rocks.Lithofacies can be divided into five types,including clastic rock assemblage,clastic rock-limestone assemblage,limestone assemblage,limestone-siliceous rock assemblage,and siliceous rock-clastic rock assemblage.Four fundamental ecological types and five fossil assemblages were recognized in the Changxing Stage.On the basis of the petrological and palaeoecological study,eight single factors were chosen including thickness,content of marine rocks,content of shallow water carbonate rocks,content of bioclasts with limemud matrix,content of bioclasts with sparry cement,distribution of reefs,content of thin bedded siliceous rocks and content of deep water sedimentary rocks.And eight single factor maps and one lithofacies paleogeographic map of the Changxing Stage were compiled.Paleoenvironments from west to east include an erosional area,fluvial plain,clastic platform,carbonate platform and reefs that developed there,slope and basin,low energy organic banks,and high energy organic banks.Sedimentary environments have an obvious control on the development of the source rocks,and the excellent source rocks are developed in the Dalong Formation.Changxing Stage reservoirs should be dominated by the reef and platform surrounding the GuangyuanLiangping Basin rim area,and is the most favorable exploration area of the reef petroleum reservoirs of the Changxing Formation.展开更多
Lithofacies palaeogeography as a guide to petroleum exploration is a very important topic.By using the following five exploration examples,this paper discusses the guide of lithofacies palaeogeography or of sedimentar...Lithofacies palaeogeography as a guide to petroleum exploration is a very important topic.By using the following five exploration examples,this paper discusses the guide of lithofacies palaeogeography or of sedimentary facies to petroleum exploration.These examples include the dolostone of the Lower Ordovician Majiagou Formation 5 in the Ordos area,the Donghe Sandstone of the Upper Devonian and Lower Carboniferous in the Tarim Basin,the reef of the Upper Permian Changxing Formation in the Sichuan Basin,the oolitic bank of the Lower Triassic Feixianguan Formation in the Sichuan Basin,and the lacustrine delta sediments and gravity flow sediments of the Middle and Upper Triassic Yanchang Formation in the Ordos Basin.展开更多
Quantitative lithofacies palaeogeography is an important discipline of palaeogeography.It is developed on the foundation of traditional lithofacies palaeogeography and palaeogeography,the core of which is the quantita...Quantitative lithofacies palaeogeography is an important discipline of palaeogeography.It is developed on the foundation of traditional lithofacies palaeogeography and palaeogeography,the core of which is the quantitative lithofacies palaeogeographic map.Quantity means that in the palaeogeographic map,the division and identification of each palaeogeographic unit are supported by quantitative data and quantitative fundamental maps.Our lithofacies palaeogeographic maps are quantitative or mainly quantitative.A great number of quantitative lithofacies palaeogeographic maps have been published,and articles and monographs of quantitative lithofacies palaeogeography have been published successively,thus the quantitative lithofacies palaeogeography was formed and established.It is an important development in lithofacies palaeogeography.In composing quantitative lithofacies palaeogeographic maps,the key measure is the single factor analysis and multifactor comprehensive mapping method—methodology of quantitative lithofacies palaeogeography.In this paper,the authors utilize two case studies,one from the Early Ordovician of South China and the other from the Early Ordovician of Ordos,North China,to explain how to use this methodology to compose the quantitative lithofacies palaeogeographic maps,and to discuss the palaeogeographic units in these maps.Finally,three characteristics,i.e.,quantification,multiple orders and multiple types,of quantitative lithofacies palaeogeographic maps are conclusively discussed.展开更多
Based on the lithologies,sedimentary structures,graptolite zones,inorganic geochemical characteristics,electrical data of 110 shale gas wells in southern Sichuan Basin and the mineral quantitative analysis technology ...Based on the lithologies,sedimentary structures,graptolite zones,inorganic geochemical characteristics,electrical data of 110 shale gas wells in southern Sichuan Basin and the mineral quantitative analysis technology of scanning electron microscope,the stratigraphic sequences of the Upper Ordovician Katian Stage-Himantian Stage-Silurian Rhuddanian Stage-Aeronian Stage are divided,the sedimentary characteristics and fourth-order sequence evolution are analyzed.The target layer can be divided into two sequences,namely SQ1 and SQ2.According to Ordovician-Silurian sedimentary background,the gamma value of the target layer and U/Th,5 maximum flooding surfaces and 12 system tracts are identified.According to system tracts and their combinations,eight fourth-order sequences are identified,namely,Pss1-Pss8 from old to new.The development period and scale of dominant shale facies from Katian stage to Aeronian stage in southern Sichuan are restored.The best-quality dolomite/calcite-bearing siliceous shale facies,siliceous shale facies,clay-bearing siliceous shale facies and feldspar-bearing siliceous shale facies mainly occur in Pss3-Pss5 of Weiyuan,Western Chongqing and Luzhou,Pss6 of Western Changning-Northern Luzhou-Central Western Chongqing and Pss3-Pss4 of Changning.The siliceous clay shale facies second in quality mainly occurs in Pss6 of Southern Luzhou-Changning area(excluding Western Changning area),Pss7 of Eastern Weiyuan-Northern Western Chongqing-Southern Luzhou and Pss8 of Northern Luzhou-Weiyuan-Western Chongqing.The fourth-order sequence evolution model of Katian stage-Aeronian stage in southern Sichuan is established.During the depositional period of Pss1-Pss8,the sea level had six regressions and five transgressions,and the first transgression SQ2-MFS1 after glaciation was the largest flooding surface.展开更多
Analysis of Sinian outcrops in the peripheral regions of the Tarim Basin,drilling and seismic data within the Tarim Basin,and combined with previous studies,distribution of Sinian strata,tectonic setting,sedimentary s...Analysis of Sinian outcrops in the peripheral regions of the Tarim Basin,drilling and seismic data within the Tarim Basin,and combined with previous studies,distribution of Sinian strata,tectonic setting,sedimentary system and lithofacies palaeogeography were well discussed.Results showed that three sedimentary systems were developed in the Sinian System of the Tarim Basin,i.e.the clastic sedimentary system,the clastic-carbonate mixed sedimentary system,and the carbonate sedimentary system,vertical sedimentary characteristics evolved from the clastic sedimentary system to the carbonate sedimentary system.These three sedimentary systems were corresponded to three transgression-regression cycles in the Sinian.The marine transgression during the initial period of the Early Sinian(ZSQI)resulted in development of the clastic sedimentary system in the lower part of the Lower Sinian;the transgression during the late period of the Early Sinian(ZSQII)led to formation of the clastic-carbonate mixed sedimentary system in the upper part of the Lower Sinian;the transgression during the initial period of the Late Sinian(ZSQIII)resulted in development of carbonate sedimentary system in the Upper Sinian.Three regressions resulted in formation of three unconformities,which were on the middle part of the Lower Sinian,the top of the Lower Sinian and the top of the Upper Sinian respectively.Due to breakup of Rodinia supercontinent in the Neoproterozoic,the Tarim Basin was in the continental rifting evolutionary process.In the Sinian,the basin experienced evolutionary processes of intra-cratonic depression and passive continental margin,thus characteristic of the lithofacies palaeogeography was characterized by uplifts in the south and depressions in the north.In the Early Sinian,the Tarim Basin developed the Bachu-Tazhong-Tadongnan uplift and the Tabei residual ancient land,and the shore-shelf sedimentary environment in the north as well as the shore-shelf-bathyal sedimentary environment in the southwest.In the Late Sinian,the Tabei residual ancient land disappeared;the basin developed the tidal flat sedimentary environment in the north and the neritic sedimentary environment of the passive continental margin in the southwest.展开更多
基金financially supported by National Science and Technology Major Project of the Chinese Ministry of Science and Technology (No.2011ZX05031-001-007HZ)
文摘The North Carnarvon Basin, which lies in the North West Shelf of Australia, is highly rich in gas resources. As a typical passive marginal basin, it experienced the pre-rifting, early rifting, main rifting, late rifting, post-rifting sagging and passive margin stages. The basin was mainly filled with thick Mesozoic-Cenozoic sediments, of which the Mesozoic hosts the principal source, reservoir and seal intervals. Mesozoic palaeogeography has an important control on the oil and gas distribution. Triassic gas-prone source rocks of deltaic origin deter-mine the high endowment of natural gases in the North Carnarvon Basin. The more restricted distribution of oil accumulations is controlled by oil source rocks in the Upper Jurassic Dingo Claystone. The Muderong Shale deposited in the Early Cretaceous marine transgression provides the effective regional seal for the underlying oil and gas reservoirs.
基金supported by the Twelfth Five-Year Plan of major national science and technology project "Study on accumulation conditions and favorable exploration area evaluation of marine carbonate rocks in South China" (2011ZX05004-001-004)
文摘The lithofacies palaeogeography of the Late Permian Wujiaping Age in Middle and Upper Yangtze Region was studied based on petrography and the ＂single factor analysis and multifactor comprehensive mapping＂ method. The Upper Permian Wujiaping Stage in the Middle and Upper Yangtze Region is mainly composed of carbonate rocks and clastic rocks, with lesser amounts of siliceous rocks, pyroclastic rocks, volcanic rocks and coal. The rocks can be divided into three types, including clastic rock, clastic rock-limestone and limestone-siliceous rock, and four fundamental ecological types and four fossil assemblages are recognized in the Wujiaping Stage. Based on a petrological and palaeoecological study, six single factors were selected, namely, thickness （m）, content （%） of marine rocks, content （%） of shallow water carbonate rocks, content （%） of biograins with limemud, content （%） of thinbedded siliceous rocks and content （%） of deep water sedimentary rocks. Six single factors maps of the Wujiaping Stage and one lithofacies palaeogeography map of the Wujiaping Age were composed. Palaeogeographic units from west to east include an eroded area, an alluvial plain, a clastic rock platform, a carbonate rock platform where biocrowds developed, a slope and a basin. In addition, a clastic rock platform exists in the southeast of the study area. Hydro- carbon source rock and reservoir conditions were preliminarily analyzed based on lithofacies palaeogeography. Sedimentary environments have obvious controls over the development of the resource rocks. With regard to the abundance of organic matter, the hydrocarbon potential of the coastal swamp environment is the best, followed by the basin environment and the carbonate rock platform. The gas reservoir types of the Wujiaping Stage can be classified as conventional and unconventional gas reservoirs, like coal bed gas and shale gas; all of them have well exploration prospects.
基金supported by the marine petroleum exploration project "Study of the quantitative lithofacies,palaeogeography and petroleum predication of Permian in South China" from China Petroleum & Chemical Corporation(YPH08019)the twelfth Five-Year Plan of major national science and technology project " Study on accumulation conditions and favorable exploration area evaluation of marine carbonate rocks in South China"(2011ZX05004-001-004)
文摘Based on the petrological study,according to single factor analysis and multifactor comprehensive mapping method,the quantitative lithofacies palaeogeography of the Upper Permian Changxing Stage of the Middle and Upper Yangtze Region was studied.The Changxing Stage in the Middle and Upper Yangtze Region is mainly composed of carbonate rocks;in addition,clastic and siliceous rocks occur with rare coals and pyroclastic rocks.Lithofacies can be divided into five types,including clastic rock assemblage,clastic rock-limestone assemblage,limestone assemblage,limestone-siliceous rock assemblage,and siliceous rock-clastic rock assemblage.Four fundamental ecological types and five fossil assemblages were recognized in the Changxing Stage.On the basis of the petrological and palaeoecological study,eight single factors were chosen including thickness,content of marine rocks,content of shallow water carbonate rocks,content of bioclasts with limemud matrix,content of bioclasts with sparry cement,distribution of reefs,content of thin bedded siliceous rocks and content of deep water sedimentary rocks.And eight single factor maps and one lithofacies paleogeographic map of the Changxing Stage were compiled.Paleoenvironments from west to east include an erosional area,fluvial plain,clastic platform,carbonate platform and reefs that developed there,slope and basin,low energy organic banks,and high energy organic banks.Sedimentary environments have an obvious control on the development of the source rocks,and the excellent source rocks are developed in the Dalong Formation.Changxing Stage reservoirs should be dominated by the reef and platform surrounding the GuangyuanLiangping Basin rim area,and is the most favorable exploration area of the reef petroleum reservoirs of the Changxing Formation.
文摘Lithofacies palaeogeography as a guide to petroleum exploration is a very important topic.By using the following five exploration examples,this paper discusses the guide of lithofacies palaeogeography or of sedimentary facies to petroleum exploration.These examples include the dolostone of the Lower Ordovician Majiagou Formation 5 in the Ordos area,the Donghe Sandstone of the Upper Devonian and Lower Carboniferous in the Tarim Basin,the reef of the Upper Permian Changxing Formation in the Sichuan Basin,the oolitic bank of the Lower Triassic Feixianguan Formation in the Sichuan Basin,and the lacustrine delta sediments and gravity flow sediments of the Middle and Upper Triassic Yanchang Formation in the Ordos Basin.
文摘Quantitative lithofacies palaeogeography is an important discipline of palaeogeography.It is developed on the foundation of traditional lithofacies palaeogeography and palaeogeography,the core of which is the quantitative lithofacies palaeogeographic map.Quantity means that in the palaeogeographic map,the division and identification of each palaeogeographic unit are supported by quantitative data and quantitative fundamental maps.Our lithofacies palaeogeographic maps are quantitative or mainly quantitative.A great number of quantitative lithofacies palaeogeographic maps have been published,and articles and monographs of quantitative lithofacies palaeogeography have been published successively,thus the quantitative lithofacies palaeogeography was formed and established.It is an important development in lithofacies palaeogeography.In composing quantitative lithofacies palaeogeographic maps,the key measure is the single factor analysis and multifactor comprehensive mapping method—methodology of quantitative lithofacies palaeogeography.In this paper,the authors utilize two case studies,one from the Early Ordovician of South China and the other from the Early Ordovician of Ordos,North China,to explain how to use this methodology to compose the quantitative lithofacies palaeogeographic maps,and to discuss the palaeogeographic units in these maps.Finally,three characteristics,i.e.,quantification,multiple orders and multiple types,of quantitative lithofacies palaeogeographic maps are conclusively discussed.
基金Supported by the Petro China Major Engineering Technology Field Test Project(2019F-31-01)Postdoctoral Project of Petro China Southwest Oil and Gas Field Company(20200304-03)。
文摘Based on the lithologies,sedimentary structures,graptolite zones,inorganic geochemical characteristics,electrical data of 110 shale gas wells in southern Sichuan Basin and the mineral quantitative analysis technology of scanning electron microscope,the stratigraphic sequences of the Upper Ordovician Katian Stage-Himantian Stage-Silurian Rhuddanian Stage-Aeronian Stage are divided,the sedimentary characteristics and fourth-order sequence evolution are analyzed.The target layer can be divided into two sequences,namely SQ1 and SQ2.According to Ordovician-Silurian sedimentary background,the gamma value of the target layer and U/Th,5 maximum flooding surfaces and 12 system tracts are identified.According to system tracts and their combinations,eight fourth-order sequences are identified,namely,Pss1-Pss8 from old to new.The development period and scale of dominant shale facies from Katian stage to Aeronian stage in southern Sichuan are restored.The best-quality dolomite/calcite-bearing siliceous shale facies,siliceous shale facies,clay-bearing siliceous shale facies and feldspar-bearing siliceous shale facies mainly occur in Pss3-Pss5 of Weiyuan,Western Chongqing and Luzhou,Pss6 of Western Changning-Northern Luzhou-Central Western Chongqing and Pss3-Pss4 of Changning.The siliceous clay shale facies second in quality mainly occurs in Pss6 of Southern Luzhou-Changning area(excluding Western Changning area),Pss7 of Eastern Weiyuan-Northern Western Chongqing-Southern Luzhou and Pss8 of Northern Luzhou-Weiyuan-Western Chongqing.The fourth-order sequence evolution model of Katian stage-Aeronian stage in southern Sichuan is established.During the depositional period of Pss1-Pss8,the sea level had six regressions and five transgressions,and the first transgression SQ2-MFS1 after glaciation was the largest flooding surface.
基金The workwas supported by China Geological Survey Project(No.DD20160175-1-1)the National Natural Science Foundation of China(No.41272137,No.41572117).
文摘Analysis of Sinian outcrops in the peripheral regions of the Tarim Basin,drilling and seismic data within the Tarim Basin,and combined with previous studies,distribution of Sinian strata,tectonic setting,sedimentary system and lithofacies palaeogeography were well discussed.Results showed that three sedimentary systems were developed in the Sinian System of the Tarim Basin,i.e.the clastic sedimentary system,the clastic-carbonate mixed sedimentary system,and the carbonate sedimentary system,vertical sedimentary characteristics evolved from the clastic sedimentary system to the carbonate sedimentary system.These three sedimentary systems were corresponded to three transgression-regression cycles in the Sinian.The marine transgression during the initial period of the Early Sinian(ZSQI)resulted in development of the clastic sedimentary system in the lower part of the Lower Sinian;the transgression during the late period of the Early Sinian(ZSQII)led to formation of the clastic-carbonate mixed sedimentary system in the upper part of the Lower Sinian;the transgression during the initial period of the Late Sinian(ZSQIII)resulted in development of carbonate sedimentary system in the Upper Sinian.Three regressions resulted in formation of three unconformities,which were on the middle part of the Lower Sinian,the top of the Lower Sinian and the top of the Upper Sinian respectively.Due to breakup of Rodinia supercontinent in the Neoproterozoic,the Tarim Basin was in the continental rifting evolutionary process.In the Sinian,the basin experienced evolutionary processes of intra-cratonic depression and passive continental margin,thus characteristic of the lithofacies palaeogeography was characterized by uplifts in the south and depressions in the north.In the Early Sinian,the Tarim Basin developed the Bachu-Tazhong-Tadongnan uplift and the Tabei residual ancient land,and the shore-shelf sedimentary environment in the north as well as the shore-shelf-bathyal sedimentary environment in the southwest.In the Late Sinian,the Tabei residual ancient land disappeared;the basin developed the tidal flat sedimentary environment in the north and the neritic sedimentary environment of the passive continental margin in the southwest.
