The complex evolutionary history of the Qinghai-Tibetan Plateau and its surrounding areas,including the continental blocks(Indian,Lhasa,South Qiangtang,Tarim,Olongbuluk,Central Qilian,Alxa,North China,Yangtze,Central ...The complex evolutionary history of the Qinghai-Tibetan Plateau and its surrounding areas,including the continental blocks(Indian,Lhasa,South Qiangtang,Tarim,Olongbuluk,Central Qilian,Alxa,North China,Yangtze,Central Iran and Oman)and the orogenic belts between them,has long been the frontier in Earth science research.The Cryogenian and Ediacaran strata are extensively distributed in these blocks.Specifically,relatively complete Cryogenian and Ediacaran successions have been discovered in Oman,Indian,Yangtze,and Tarim blocks,while only the Ediacaran successions have been reported in Iran,the South Qiangtang,Central Qilian,Alxa,and North China blocks.Based on previous studies together with the integration of new materials and advancement obtained through the Second Tibetan Plateau Scientific Expedition and Research,this review aims to synthesize a correlative stratigraphic framework of the representative Cryogenian and Ediacaran sequences from the Qinghai-Tibetan Plateau and its surrounding areas.Furthermore,the Cryogenian and Ediacaran biotas and major geological events in these areas are comprehensively discussed in aspects of current research status.The results indicate that,in general,Ediacaran fossils of each area exhibit distinct features in preservation and assemblage composition,but the typical late Ediacaran fossils Cloudina and Shaanxilithes have been reported from most of these areas.In addition to the two global Cryogenian glaciations,late Ediacaran glaciogenic deposits are extensively recorded in the areas within and around the northern QinghaiTibetan Plateau(including the North China,Alxa,Central Qilian,Olongbuluk,and Tarim blocks,and the North Qilian Accretionary Belt),as well as central and southern Iran.However,further research is required to determine the age,distribution,and origin of these late Ediacaran glaciogenic deposits.Meanwhile,the middle Ediacaran DOUNCE/Shuram Excursion is widely documented in the Qinghai-Tibetan Plateau and its surrounding areas.The available data show that,after the break-up of the Rodinia supercontinent,most of the continental blocks in the areas were located along the northern margin of East Gondwana and a few(such as North China)were located between the Gondwana and Laurentia.In general,the paleogeographic evolution of most of these blocks during the Cryogenian and Ediacaran remains disputatious,necessitating further research to resolve the controversies surrounding their paleogeographic reconstruction models during this critical time interval.展开更多
The Qinghai-Tibetan Plateau and its surrounding areas have a long and complex tectonic evolutionary history.Cratons and blocks,such as northern India,Lhasa,Qiangtang,Qaidam and Central Qilian,and their in-between orog...The Qinghai-Tibetan Plateau and its surrounding areas have a long and complex tectonic evolutionary history.Cratons and blocks,such as northern India,Lhasa,Qiangtang,Qaidam and Central Qilian,and their in-between orogenic belts constitute the main part of the Qinghai-Tibetan Plateau.During the Cambrian Period,most of these cratons and blocks were on the northwestern periphery of Gondwana,and were associated with the surrounding blocks,e.g.Arabian,Central Iran,Afghanistan,Tarim,Alxa,North China,South China and Sibumasu through the Proto-Tethys Ocean.The Cambrian stratigraphic sequences on these stable blocks are composed of mixed siliciclastic and carbonate rocks deposited in the shallow-water marine environments,and contain the trilobite assemblages of shelf facies.The Cambrian stratigraphic sequences in the Qilian tectonic belts,however,are characterized by the intermediate-basic igneous rocks and silicates formed in the Proto-Tethys Ocean,and contain the trilobite assemblages of deep-water slope facies.Combining with previous data,field observations and newly discovered fossils through funding by the Second Tibetan Plateau Scientific Expedition and Research,the general characteristics of the Cambrian strata in different tectonic units of the Qinghai-Tibetan Plateau and its surrounding areas have been summarized in this paper.Furthermore,efforts have been made to subdivide and correlate the Cambrian strata across these areas by utilizing available biostratigraphic and geochronological data.As a result,a comprehensive litho-and biostratigraphy chart has been compiled.Finally,from the biogeographic perspective,this paper also provides a brief overview of the Cambrian paleogeographical reconstruction of the major tectonic blocks,and discusses the problems associated with the evolution of the ProtoTethys tectonic belt.展开更多
The Qinghai-Tibetan Plateau(QTP)is well known as the Roof of the World,the Third Pole and the Asian Water Tower.It spans a vast area from the Pamir Plateau in the west to the Longmenshan-Hengduan Mountains in the east...The Qinghai-Tibetan Plateau(QTP)is well known as the Roof of the World,the Third Pole and the Asian Water Tower.It spans a vast area from the Pamir Plateau in the west to the Longmenshan-Hengduan Mountains in the east,from the Himalaya Mountains in the south to the Kunlun-Qilian Mountains in the north.It stretches approximately 1,200 km from north to south and 2,500 km from east to west.When did the QTP start to uplift?This is still controversial between early and late Cenozoic scenarios.While some scholars advocated its uplift since the India-Asia continental collision at about 65 million years ago in the Paleogene(e.g.,Ding et al.,2017,2022),and the others suggested its uplift since the Miocene(Zheng and Wu,2018).展开更多
水是维持地球生物多样性和生态系统健康的根本保障,更是地球表层系统机体运作的“血液”.当今全球变暖背景下,与水循环变化密切相关的干旱、森林大火和洪涝等极端灾害天气频发,以及海平面上升、海洋热浪与酸化等全球性生态危机问题日益...水是维持地球生物多样性和生态系统健康的根本保障,更是地球表层系统机体运作的“血液”.当今全球变暖背景下,与水循环变化密切相关的干旱、森林大火和洪涝等极端灾害天气频发,以及海平面上升、海洋热浪与酸化等全球性生态危机问题日益突出,深刻影响了全球生态系统健康和人类社会的可持续发展.政府间气候变化专门委员会(Intergovernmental Panel on Climate Change,IPCC)第6次评估报告中,特别突出了系统性评估气候变化对全球水循环影响的重要性[1].毋容置疑,水循环是地球系统中的基本过程之一.展开更多
The Cambrian Period is the first period of the Phanerozoic Eon and witnessed the explosive appearance of the metazoans, representing the beginning of the modern earth-life system characterized by animals in contrary t...The Cambrian Period is the first period of the Phanerozoic Eon and witnessed the explosive appearance of the metazoans, representing the beginning of the modern earth-life system characterized by animals in contrary to the Precambrian earth-life system dominated by microbial life. However, understanding Cambrian earth-life system evolution is hampered by regional and global stratigraphic correlations due to an incomplete chronostratigraphy and consequent absence of a highresolution timescale. Here we briefly review the historical narrative of the present international chronostratigraphic framework of the Cambrian System and summarize recent advances and problems of the undefined Cambrian stage GSSPs, in particular we challenge the global correlation of the GSSP for the Cambrian base, in addition to Cambrian chemostratigraphy and geochronology. Based on the recent advances of the international Cambrian chronostratigraphy, revisions to the Cambrian chronostratigraphy of China, which are largely based on the stratigraphic record of South China, are suggested, and the Xiaotanian Stage is newly proposed for the Cambrian Stage 2 of China. We further summarize the integrative stratigraphy of South China, North China and Tarim platforms respectively with an emphasis on the facies variations of the Precambrian-Cambrian boundary successions and problems for identification of the Cambrian base in the different facies and areas of China. Moreover, we discuss stratigraphic complications that are introduced by poorly fossiliferous dolomite successions in the upper Cambrian System which are widespread in South China, North China and Tarim platforms.展开更多
The Neoproterozoic-Cambrian(N-C) and Permian-Triassic(P-T) transitions have been regarded the two most critical transitions in earth history because of the explosive biological radiation in the early Cambrian(the Camb...The Neoproterozoic-Cambrian(N-C) and Permian-Triassic(P-T) transitions have been regarded the two most critical transitions in earth history because of the explosive biological radiation in the early Cambrian(the Cambrian Explosion) and the largest mass extinction at the end-Permian.Previous studies suggest that these two critical transitions showed certain comparability in major evolutionary events.In other words,a series of biological,geological,and geochemical events that had happened in the N-C transition occurred repeatedly during the P-T transition.Those events included continental re-configuration related to the deep mantle dynamics,global-scale glaciations,large C-,Sr-,and S-isotope perturbations indicating atmospheric and oceanic changes,abnormal precipitation of carbonates,and associated multiple biological radiations and mass extinctions.The coupling of those events in both N-C and P-T transitions suggests that deep mantle dynamics could be a primary mechanism driving dramatic changes of environment on the earth's surface,which in turn caused major biological re-organizations.A detailed comparison of those events during the two critical transitions indicates that despite their general comparability,significant differences do exist in magnitude,duration,and frequency.The supercontinent Rodinia began to rift before the Snowball Earth time.By contrast,the supercontinent Pangea entered the dispersal stage after the greatest glaciation from the Late Carboniferous to Cisuralian.Quantitative data and qualitative analyses of different fossil groups show a more profound mass extinction during the N-C transition than at the end-Permian in terms of ecosystem disruption.This is indicated by the disappearance of the whole Ediacaran biota at the N-C boundary.The subsequent appearances of many new complex animals at phylum level in the early Cambrian mark the establishment of a brand new ecosystem.However,the end-Permian mass extinction is manifested mainly by the extinction of many different taxa at class and order levels.Although it caused the extinction of 95% of marine species and 75% of terrestrial species as well as complete cessation of coal and reef deposits after the mass extinction,this high-level biological re-organization still occurred within an established ecosystem,however drastic it may seem.Survived or Lazarus taxa re-occupied the existing ecospace in a relatively short duration after the end-Permian mass extinction.C-isotope excursions display large perturbations during both transitions,yet also in different magnitudes and frequencies,which suggest different atmospheric and oceanic conditions.The recurrent geological and geochemical events as well as the coupled major biological turnovers during the two transitions provide new clues to understanding the interplays among the earth-life system.Thus,it is essential to carry out multidisciplinary studies from the deep internal system to the surface of the Earth as a whole in order to unravel the interactions of different spheres of the earth.展开更多
A new Chengjiang-type fossil assemblage is reported herein from the lower part of the Hongjingshao Formation at Xiazhuang village of Chenggong,Kunming,Yunnan.The fossil assemblage,named as Xiazhuang fossil assemblage,...A new Chengjiang-type fossil assemblage is reported herein from the lower part of the Hongjingshao Formation at Xiazhuang village of Chenggong,Kunming,Yunnan.The fossil assemblage,named as Xiazhuang fossil assemblage,yields predominantly soft-bodied fossils,including arthropods,brachiopods,priapulids,lobopods and some problematic taxa,with arthropods being the most dominant group.Preservation and composition of the fossil assemblage are very similar to the typical Chengjiang biota,which is preserved in the middle Yu’anshan Formation in the large area of eastern Yunnan.The associated trilobites demonstrate that the soft-bodied fossil assemblage belongs to the late Qiongzhusian in age(Stage 3,Cambrian),suggesting that the Hongjingshao Formation is probably a diachronous lithostratigraphic unit ranging from the upper Qiongzhusian to the lower Canglangpuan stages in eastern Yunnan.The fossil assemblage from the Xiazhuang area fills up the missing link between the typical older Chengjiang biota and the younger Malong and Guanshan biotas,making eastern Yunnan a unique area in the world to reveal the early evolutionary history of animals and palaeocommunity dynamics during the‘‘Cambrian explosion’’.展开更多
The buildup of oxygen in the Earth's atmosphere and oceans has fundamentally reshaped the dynamics of nearly all major biogeochemical cycles and ultimately paved the way for the diversification of complex life on Ear...The buildup of oxygen in the Earth's atmosphere and oceans has fundamentally reshaped the dynamics of nearly all major biogeochemical cycles and ultimately paved the way for the diversification of complex life on Earth. Over the past decades there have been sustained efforts to develop a more comprehensive understanding of ocean-atmosphere redox evolution and its relationship to the evolution of early life (Fig. 1). It is generally accepted that the development of oxygenic photosynthesis at ~2.7 Ga may have been responsible for the Great Oxidation Event (GOE) at the beginning of the Proterozoic Eon, whereas a second big O2 rise at the end of the Proterozoic Eon (the so-called Neoproterozoic Oxidation Event or NOE) was responsible for the diversification of metazoans (Lyons et al., 2014).展开更多
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(Grant No.2019QZKK0706)the National Natural Science Foundation of China(Grant No.41921002)。
文摘The complex evolutionary history of the Qinghai-Tibetan Plateau and its surrounding areas,including the continental blocks(Indian,Lhasa,South Qiangtang,Tarim,Olongbuluk,Central Qilian,Alxa,North China,Yangtze,Central Iran and Oman)and the orogenic belts between them,has long been the frontier in Earth science research.The Cryogenian and Ediacaran strata are extensively distributed in these blocks.Specifically,relatively complete Cryogenian and Ediacaran successions have been discovered in Oman,Indian,Yangtze,and Tarim blocks,while only the Ediacaran successions have been reported in Iran,the South Qiangtang,Central Qilian,Alxa,and North China blocks.Based on previous studies together with the integration of new materials and advancement obtained through the Second Tibetan Plateau Scientific Expedition and Research,this review aims to synthesize a correlative stratigraphic framework of the representative Cryogenian and Ediacaran sequences from the Qinghai-Tibetan Plateau and its surrounding areas.Furthermore,the Cryogenian and Ediacaran biotas and major geological events in these areas are comprehensively discussed in aspects of current research status.The results indicate that,in general,Ediacaran fossils of each area exhibit distinct features in preservation and assemblage composition,but the typical late Ediacaran fossils Cloudina and Shaanxilithes have been reported from most of these areas.In addition to the two global Cryogenian glaciations,late Ediacaran glaciogenic deposits are extensively recorded in the areas within and around the northern QinghaiTibetan Plateau(including the North China,Alxa,Central Qilian,Olongbuluk,and Tarim blocks,and the North Qilian Accretionary Belt),as well as central and southern Iran.However,further research is required to determine the age,distribution,and origin of these late Ediacaran glaciogenic deposits.Meanwhile,the middle Ediacaran DOUNCE/Shuram Excursion is widely documented in the Qinghai-Tibetan Plateau and its surrounding areas.The available data show that,after the break-up of the Rodinia supercontinent,most of the continental blocks in the areas were located along the northern margin of East Gondwana and a few(such as North China)were located between the Gondwana and Laurentia.In general,the paleogeographic evolution of most of these blocks during the Cryogenian and Ediacaran remains disputatious,necessitating further research to resolve the controversies surrounding their paleogeographic reconstruction models during this critical time interval.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research(Grant No.2019QZKK0706)the National Natural Science Foundation of China(Grant No.41921002)。
文摘The Qinghai-Tibetan Plateau and its surrounding areas have a long and complex tectonic evolutionary history.Cratons and blocks,such as northern India,Lhasa,Qiangtang,Qaidam and Central Qilian,and their in-between orogenic belts constitute the main part of the Qinghai-Tibetan Plateau.During the Cambrian Period,most of these cratons and blocks were on the northwestern periphery of Gondwana,and were associated with the surrounding blocks,e.g.Arabian,Central Iran,Afghanistan,Tarim,Alxa,North China,South China and Sibumasu through the Proto-Tethys Ocean.The Cambrian stratigraphic sequences on these stable blocks are composed of mixed siliciclastic and carbonate rocks deposited in the shallow-water marine environments,and contain the trilobite assemblages of shelf facies.The Cambrian stratigraphic sequences in the Qilian tectonic belts,however,are characterized by the intermediate-basic igneous rocks and silicates formed in the Proto-Tethys Ocean,and contain the trilobite assemblages of deep-water slope facies.Combining with previous data,field observations and newly discovered fossils through funding by the Second Tibetan Plateau Scientific Expedition and Research,the general characteristics of the Cambrian strata in different tectonic units of the Qinghai-Tibetan Plateau and its surrounding areas have been summarized in this paper.Furthermore,efforts have been made to subdivide and correlate the Cambrian strata across these areas by utilizing available biostratigraphic and geochronological data.As a result,a comprehensive litho-and biostratigraphy chart has been compiled.Finally,from the biogeographic perspective,this paper also provides a brief overview of the Cambrian paleogeographical reconstruction of the major tectonic blocks,and discusses the problems associated with the evolution of the ProtoTethys tectonic belt.
基金supported by the Second Expedition of QTP Project(Grant No.2019QZKK0706)the National Natural Science Foundation of China(Grant No.42293280)。
文摘The Qinghai-Tibetan Plateau(QTP)is well known as the Roof of the World,the Third Pole and the Asian Water Tower.It spans a vast area from the Pamir Plateau in the west to the Longmenshan-Hengduan Mountains in the east,from the Himalaya Mountains in the south to the Kunlun-Qilian Mountains in the north.It stretches approximately 1,200 km from north to south and 2,500 km from east to west.When did the QTP start to uplift?This is still controversial between early and late Cenozoic scenarios.While some scholars advocated its uplift since the India-Asia continental collision at about 65 million years ago in the Paleogene(e.g.,Ding et al.,2017,2022),and the others suggested its uplift since the Miocene(Zheng and Wu,2018).
文摘水是维持地球生物多样性和生态系统健康的根本保障,更是地球表层系统机体运作的“血液”.当今全球变暖背景下,与水循环变化密切相关的干旱、森林大火和洪涝等极端灾害天气频发,以及海平面上升、海洋热浪与酸化等全球性生态危机问题日益突出,深刻影响了全球生态系统健康和人类社会的可持续发展.政府间气候变化专门委员会(Intergovernmental Panel on Climate Change,IPCC)第6次评估报告中,特别突出了系统性评估气候变化对全球水循环影响的重要性[1].毋容置疑,水循环是地球系统中的基本过程之一.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41672029, 41661134048)the Strategic Priority Research Program (B) of the Chinese Academy of Sciences (Grant Nos. XDB18000000, XDB10010101)
文摘The Cambrian Period is the first period of the Phanerozoic Eon and witnessed the explosive appearance of the metazoans, representing the beginning of the modern earth-life system characterized by animals in contrary to the Precambrian earth-life system dominated by microbial life. However, understanding Cambrian earth-life system evolution is hampered by regional and global stratigraphic correlations due to an incomplete chronostratigraphy and consequent absence of a highresolution timescale. Here we briefly review the historical narrative of the present international chronostratigraphic framework of the Cambrian System and summarize recent advances and problems of the undefined Cambrian stage GSSPs, in particular we challenge the global correlation of the GSSP for the Cambrian base, in addition to Cambrian chemostratigraphy and geochronology. Based on the recent advances of the international Cambrian chronostratigraphy, revisions to the Cambrian chronostratigraphy of China, which are largely based on the stratigraphic record of South China, are suggested, and the Xiaotanian Stage is newly proposed for the Cambrian Stage 2 of China. We further summarize the integrative stratigraphy of South China, North China and Tarim platforms respectively with an emphasis on the facies variations of the Precambrian-Cambrian boundary successions and problems for identification of the Cambrian base in the different facies and areas of China. Moreover, we discuss stratigraphic complications that are introduced by poorly fossiliferous dolomite successions in the upper Cambrian System which are widespread in South China, North China and Tarim platforms.
基金supported by National Basic Research Program of China (Grant Nos. 2006CB860400, 2011CB808905)Chinese Academy of Sciences (Grant No. KZCX2-YW-Q08-4)NSFC and the CAS/SAFEA International Partnership Program for Creative Research Teams
文摘The Neoproterozoic-Cambrian(N-C) and Permian-Triassic(P-T) transitions have been regarded the two most critical transitions in earth history because of the explosive biological radiation in the early Cambrian(the Cambrian Explosion) and the largest mass extinction at the end-Permian.Previous studies suggest that these two critical transitions showed certain comparability in major evolutionary events.In other words,a series of biological,geological,and geochemical events that had happened in the N-C transition occurred repeatedly during the P-T transition.Those events included continental re-configuration related to the deep mantle dynamics,global-scale glaciations,large C-,Sr-,and S-isotope perturbations indicating atmospheric and oceanic changes,abnormal precipitation of carbonates,and associated multiple biological radiations and mass extinctions.The coupling of those events in both N-C and P-T transitions suggests that deep mantle dynamics could be a primary mechanism driving dramatic changes of environment on the earth's surface,which in turn caused major biological re-organizations.A detailed comparison of those events during the two critical transitions indicates that despite their general comparability,significant differences do exist in magnitude,duration,and frequency.The supercontinent Rodinia began to rift before the Snowball Earth time.By contrast,the supercontinent Pangea entered the dispersal stage after the greatest glaciation from the Late Carboniferous to Cisuralian.Quantitative data and qualitative analyses of different fossil groups show a more profound mass extinction during the N-C transition than at the end-Permian in terms of ecosystem disruption.This is indicated by the disappearance of the whole Ediacaran biota at the N-C boundary.The subsequent appearances of many new complex animals at phylum level in the early Cambrian mark the establishment of a brand new ecosystem.However,the end-Permian mass extinction is manifested mainly by the extinction of many different taxa at class and order levels.Although it caused the extinction of 95% of marine species and 75% of terrestrial species as well as complete cessation of coal and reef deposits after the mass extinction,this high-level biological re-organization still occurred within an established ecosystem,however drastic it may seem.Survived or Lazarus taxa re-occupied the existing ecospace in a relatively short duration after the end-Permian mass extinction.C-isotope excursions display large perturbations during both transitions,yet also in different magnitudes and frequencies,which suggest different atmospheric and oceanic conditions.The recurrent geological and geochemical events as well as the coupled major biological turnovers during the two transitions provide new clues to understanding the interplays among the earth-life system.Thus,it is essential to carry out multidisciplinary studies from the deep internal system to the surface of the Earth as a whole in order to unravel the interactions of different spheres of the earth.
基金supported by the Program of Chinese Academy of Sciences(KZZD-EW-02-2)the National Basic Research Program of China(2013CB835006)+2 种基金the National NaturalScience Foundation of China(41002002,41372021,J1210006)the Natural Science Foundation of Jiangsu Province(BK2012893)the National Science and Technology Major Project(2011ZX05008)
文摘A new Chengjiang-type fossil assemblage is reported herein from the lower part of the Hongjingshao Formation at Xiazhuang village of Chenggong,Kunming,Yunnan.The fossil assemblage,named as Xiazhuang fossil assemblage,yields predominantly soft-bodied fossils,including arthropods,brachiopods,priapulids,lobopods and some problematic taxa,with arthropods being the most dominant group.Preservation and composition of the fossil assemblage are very similar to the typical Chengjiang biota,which is preserved in the middle Yu’anshan Formation in the large area of eastern Yunnan.The associated trilobites demonstrate that the soft-bodied fossil assemblage belongs to the late Qiongzhusian in age(Stage 3,Cambrian),suggesting that the Hongjingshao Formation is probably a diachronous lithostratigraphic unit ranging from the upper Qiongzhusian to the lower Canglangpuan stages in eastern Yunnan.The fossil assemblage from the Xiazhuang area fills up the missing link between the typical older Chengjiang biota and the younger Malong and Guanshan biotas,making eastern Yunnan a unique area in the world to reveal the early evolutionary history of animals and palaeocommunity dynamics during the‘‘Cambrian explosion’’.
文摘The buildup of oxygen in the Earth's atmosphere and oceans has fundamentally reshaped the dynamics of nearly all major biogeochemical cycles and ultimately paved the way for the diversification of complex life on Earth. Over the past decades there have been sustained efforts to develop a more comprehensive understanding of ocean-atmosphere redox evolution and its relationship to the evolution of early life (Fig. 1). It is generally accepted that the development of oxygenic photosynthesis at ~2.7 Ga may have been responsible for the Great Oxidation Event (GOE) at the beginning of the Proterozoic Eon, whereas a second big O2 rise at the end of the Proterozoic Eon (the so-called Neoproterozoic Oxidation Event or NOE) was responsible for the diversification of metazoans (Lyons et al., 2014).
基金supported by the National Basic Research Program of China(2006CB806401)the National Natural Science Foundation of China(40772020,40725005 and 40930211)
基金supported by the National Natural Science Foundation of China(41825019,42130208,41821001,and 42102343)the Programme of Introducing Talents of Discipline to Universities(BP0820004)+1 种基金China Postdoctoral Science Foundation(2020M682515)an award from “Laboratoire Excellence”LabexMER(ANR-10-LABX-19)。