The non-marine Cretaceous sequences are well developed in the relict basins, i.e. the Luxi basin in the west, and the Jiaolai basin in the east of Shandong Province. The Lower Cretaceous Santai Formation (140 - 136 Ma...The non-marine Cretaceous sequences are well developed in the relict basins, i.e. the Luxi basin in the west, and the Jiaolai basin in the east of Shandong Province. The Lower Cretaceous Santai Formation (140 - 136 Ma) in the Luxi basin contains aeolian dune deposits, which were formed under the control by westerly. The Cretaceous strata of the Jiaolai basin are divided into three groups: i.e. in ascending order, the Laiyang, Qingshan and Wangshi groups. New SHRIMP zircon U-Pb radiometric dating data demonstrated six Cretaceous volcanism episodes. The lower part of the Wangshi Group should be assigned to the upper Lower Cretaceous. An Ir anomaly recovered in the lower Jiaozhou Formation suggests that the Cretaceous/Palaeogene boundary would be in the interval between 537.3 - 537.4 m in the borehole JK1. At last the detailed information about the pre-symposium field excursion was introduced.展开更多
Clam shrimps are large bivalved branchiopod crustacean. They first occurred in the Devonian, and flourished during the Mesozoic in Asia. Fossil clam shrimps play an important role in the subdivision and correlation of...Clam shrimps are large bivalved branchiopod crustacean. They first occurred in the Devonian, and flourished during the Mesozoic in Asia. Fossil clam shrimps play an important role in the subdivision and correlation of non-marine fossil-bearing strata. The phosphatized carapaces or carapace external/internal moulds are the main objects for taxonomical studies. The delicate ornament and the ontogenetically developing morphological patterns on the growth bands of carapaces are the main fossil taxonomic criteria. While modern clam shrimp taxonomy is based on soft body morphological features and molecular data, which could not be found in the fossil records. This makes it difficult to discuss the fossil and modern clam shrimp phylogenetic relationship. Nowadays scanning electron microscopes are widely available, and can play an important role in investigating clam shrimp carapace morphology which could be common language to integrate fossil and modern taxonomy.展开更多
The Lower Cretaceous mixed siliciclastic-carbonate successions of the Boulouha Formation at the type locality in the Dahar escarpment of southern Tunisia have yielded a new discovered assemblage of bivalves which cont...The Lower Cretaceous mixed siliciclastic-carbonate successions of the Boulouha Formation at the type locality in the Dahar escarpment of southern Tunisia have yielded a new discovered assemblage of bivalves which contains Anomia laevigata (Sowerby);Modiolus sp. cf. M. dahuashuensis (Yu et Li);Astarte sp.;and ?Mytilus sp.. The temporal distribution of the Anomia laevigata (Sowerby) and Modiolus sp. cf. M. dahuashuensis (Yu et Li) is limited to the Aptian formations of northeastern China, Japan and Korea, thus we suggest a Hauterivian-Barremian age for the Boulouha Formation. Henceforth, the new biostratigraphic data are used to improve a regional chronostratigraphic correlation between the lower Cretaceous strata of the Saharan Platform domain and those coeval from the Chotts domain.展开更多
The evolutionary history of Eupolypods still remains unclear, especially on its diversification scenarios. In recent years, it has been found that approximately 100 million-year-old Myanmar amber provides a unique sou...The evolutionary history of Eupolypods still remains unclear, especially on its diversification scenarios. In recent years, it has been found that approximately 100 million-year-old Myanmar amber provides a unique source of polypod fossils. Different families and numerous sporangia, spores, and scales have been found in Myanmar amber. These discoveries are nevertheless important because they provided the first unequivocal fossil evidence that the diversity of eupolypod ferns was present already in the mid-Cretaceous Myanmar amber forest. This clearly shows that Eupolypods originated before mid-Cretaceous, probably as early as the Early Jurassic, which is consistent with the recent divergence time estimate based on molecular dating.展开更多
Normally, trees on the side directly exposed to sunlight will grow faster than the opposing side. This phenomenon is termed plant phototropism. Moreover, palaeomagnetists have revealed that the Junnar Block has never ...Normally, trees on the side directly exposed to sunlight will grow faster than the opposing side. This phenomenon is termed plant phototropism. Moreover, palaeomagnetists have revealed that the Junnar Block has never rotated since the Mesozoic. The petrified woods in the Jiangjunmiao area of Qitai County show the positive phototropism direction of SSW220. By compared with the modern normal growth stumps in plain area, which have positive phototropism direction of SSW 219 ± 5, this observation supports the conclusion of palaeomagnetic researchers: the Junggar basin has never rotated since the Late Jurassic.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
Two new coniferous wood taxa, Protocedroxylon zhangii sp. nov. and P. zhalantunense sp. nov., are described from the Middle Jurassic Wanbao Formation in Zhalantun City, Inner Mongolia, NE China. The new discovery repr...Two new coniferous wood taxa, Protocedroxylon zhangii sp. nov. and P. zhalantunense sp. nov., are described from the Middle Jurassic Wanbao Formation in Zhalantun City, Inner Mongolia, NE China. The new discovery represents the first record of petrified wood in the Wanbao Formation, and contributes to further understanding the floral composition, especially that of the forest, of the Wanbao Formation. Anatomically, the two new species are characterized by having a mixed type of radial pitting and Abietineentüpfelung. In extant conifers, Abietineentüpfelung is considered to be characteristic of the wood of Pinaceae. The new discovery further indicates that the first occurrence of Abietineentüpfelung in conifer-like wood should be earlier than the Kimmeridgian. The palaeolatitudinal distribution pattern of Protocedroxylon indicates that the genus is a palaeobiogeographically consistent group, which was probably restricted to wetter and cooler temperate climates. In combination with distinct growth rings, the occurrence of Protocedroxylon suggests that a cool temperate and seasonal climate might have prevailed during the sedimentation period of the Wanbao Formation in eastern Inner Mongolia, NE China. Such a view is also in agreement with the palaeoclimatic conditions indicated by the plant megafossils of the Wanbao Formation.展开更多
The alternating marine and nonmarine coal-bearing Lower Cretaceous successions are well developed in eastern Heilongjiang, northeastern China, including the Jixi Group in the west and the Longzhaogou Group in the east...The alternating marine and nonmarine coal-bearing Lower Cretaceous successions are well developed in eastern Heilongjiang, northeastern China, including the Jixi Group in the west and the Longzhaogou Group in the east. The correlation of these two lithostratigraphic groups with the nonmarine Jehol Group is important for dating the exceptionally well-preserved Jehol Biota. The Early Cretaceous marine fossils recovered from eastern Heilongjiang include ammonites, bivalves, radiolarians, foraminifers and dinocysts. During the early Aptian transgression the ammonite fauna entered the Hulin and Mishan areas and the bivalve Aucellina fauna in the Jixi area. This enables correlation of the marine lower part of the Chengzihe Formation of the Jixi Group with the Qihulin Formation of the Longzhaogou Group.展开更多
The latest Cretaceous strata of the Jiaolai Basin were studied in two scientific cores,including LK-1 drilled by the Institute of Geology,Chinese Academy of Geological Sciences(Li et al.,2018;Li et al.,2020),and JK-1 ...The latest Cretaceous strata of the Jiaolai Basin were studied in two scientific cores,including LK-1 drilled by the Institute of Geology,Chinese Academy of Geological Sciences(Li et al.,2018;Li et al.,2020),and JK-1 drilled by the Shandong Institute of the Geological Survey and Institute of Geology,Chinese Academy of Geological Sciences(Xu et al.,2017).However,outcrop sections were poorly studied,and the latest Cretaceous charophyte flora in particular had not previously been adequately documented from outcrops in the Jiaolai area.展开更多
Paleobiogeography investigates geographical distributions of fossil organisms and controlling factors that affect their distributions in geological history,to reveal the macro-evolution and coordinated development of ...Paleobiogeography investigates geographical distributions of fossil organisms and controlling factors that affect their distributions in geological history,to reveal the macro-evolution and coordinated development of life and the environment.It is a crucial window for understanding the biosphere and the geographical environment.After two centuries of development,paleobiogeographic studies have led to the accumulation of significant amounts of knowledge and data;however,the voluminous outputs present the characteristics of an“isolated island”with a scattered,limited number of authoritative definitions of terminologies and semantic heterogeneity among them.This makes data queries cumbersome,the rate of data reuse low,and data sharing more difficult.A knowledge graph(KG)has the advantage of expressing concepts and their semantic relations,which is an important tool for achieving data organization and fusion,and data mining;further,it is also a key technology for realizing the unrestricted sharing of paleobiogeographic information.Through our efforts over the past two years,a paleobiogeographic KG was developed based on the established construction procedure of the KG,which contains 273 concepts,172 properties,and 47 rules.Meanwhile,the completion of this KG and the construction of a paleobiogeographic platform for display and analysis are now being carried out.展开更多
Protolepidodendralean lycopsids are characteristic of morphologically complex leaves.Most taxa of this group are herbaceous and widely distributed in global Devonian sediments,with exceptions of a few members,such as ...Protolepidodendralean lycopsids are characteristic of morphologically complex leaves.Most taxa of this group are herbaceous and widely distributed in global Devonian sediments,with exceptions of a few members,such as Frenguellia eximia from the Lower Carboniferous of Argentina.In this study,we focus on the morphology of Frenguellia eximia and emend its generic and specific diagnoses,based on new materials from the Upper Devonian Hongguleleng Formation of West Junggar,Xinjiang Uygur Autonomous Region,Northwest China,within the fossil-bearing bed palynologically dated as a latest Famennian age.This is the first finding of Frenguellia eximia out of Gondwana.Frenguellia eximia bears planate leaf with three upward pairs of lateral tips,isomorphic sporophyll to the leaf,and elongated,oval sporangium.Leaf morphology of the members of the Order Protolepidodendrales is summarized and classified into lateral-tip and distal-tip types.Lateral-tip type leaf consists of an obvious main body and several paired lateral tips,whereas distal-tip type leaf shows a petiole and a distal lamina with several planate or three-dimensional segments.Two leaf types probably indicate two independent evolutionary routes of microphylls evolving from simple leaf of prelycopsids during the Devonian period.The new occurrence of Frenguellia eximia further shows paleophytogeographical similarities between West Junggar and northwestern Gondwana.展开更多
Ediacaran successions occur widely in various depositional facies in South China and yield a series of fossil Lagerst?tten, providing a complete fossil record for the evolution of marine ecosystems after the terminal ...Ediacaran successions occur widely in various depositional facies in South China and yield a series of fossil Lagerst?tten, providing a complete fossil record for the evolution of marine ecosystems after the terminal Cryogenian global glaciation. Carbonate-dominated Ediacaran successions in shallow water facies in South China record a nearly complete δ^(13)C profile that may reflect variations of marine carbon isotopic composition during the Ediacaran Period. The Ediacaran fossils andδ^(13)C profiles from South China permit stratigraphic correlation and subdivision of the Ediacaran strata. Based on biostratigraphic, chemostratigraphic, and geochronometric data from the Ediacaran successions in South China, we propose that the Ediacaran System in China can be subdivided into two series, with three stages in each series. The lower series is characterized by acanthomorphic acritarchs and the upper series by Ediacara-type macrofossils, and the two series are separated by the declining limb of a pronounced δ^(13)C negative excursion(EN3) in the upper Doushantuo Formation. The basal boundary of Stage1 is the same as the basal boundary of Ediacaran System, which has been defined at the base of the cap carbonate unit. Stage 2 represents the first radiation of Ediacaran microscopic organisms, with δ^(13)C feature representing by positive values(EP1). The base of the Stage 2 is placed at the first appearance level of a spiny acritarch species. Stage 3 is characterized by the occurrence of more diverse acritarchs and δ^(13)C feature EP2, with its basal boundary defined by a δ^(13)C negative excursion(EN2) occurring in the middle Doushantuo Formation. The basal boundary of Stage 4 is the same as the upper series. Stage 5 is marked by the occurrence of macrfossils of Miaohe biota, and its lower boundary can be placed at the level where δ^(13)C values transition from positive to negative in MNE, or the first appearance level of macrofossils of the Miaohe biota. Stage 6 is characterized by the occurrences of Ediacara-type Shibantan biota and Gaojiashan biota, with its lower boundary defined by the first appearance level of Conotubus hemiannulatus. The formal establishment of the aforementioned series and stages requires further and more detailed integrative stratigraphic study on the Ediacaran successions in China. Some of the Ediacaran successions in South China have great potential to become global standards in Ediacaran subdivision.展开更多
Lime mud(i.e.,micrite)is a major component of carbonate deposits.Various mechanisms(biotic versus abiotic)have been proposed for the formation of lime mud in Earth’s history.However,the detailed role that microbes pl...Lime mud(i.e.,micrite)is a major component of carbonate deposits.Various mechanisms(biotic versus abiotic)have been proposed for the formation of lime mud in Earth’s history.However,the detailed role that microbes play in the nucleation and subsequent precipitation of micrites remains to be resolved.Herein we undertook a detailed geobiological characterization of laminated lime mudstone from the Middle Triassic Guanling Formation in Yunnan Province,southwestern China.Morphological features,together with previous geobiological investigations,suggest that the laminated lime mudstones represent the former presence of microbial mats.These lime mudstones consist mainly of calcite,dolomite and quartz,with clay minerals and pyrites as subordinate components.In particular,micro-analysis shows copious nano-globules(65–878 nm)and capsule-shaped nano-rods in laminations.These low-Mg calcite nano-globule aggregates are closely associated with mucilaginous biofilms resembling extracellular polymeric substances(EPS).Nano-sized globules coalesce to form semi-euhedral micrite crystals.We suggest that a decaying hydrolytic destruction of the EPS by microbial communities within microbial mat leads to the precipitation of the nano-globules by enhancing alkalinity in local micro-environment.As an intermediate,these nano-globules further aggregate to form micrite crystals possibly through a dissolution-reprecipitation process.展开更多
The Ordovician-Silurian transition(OST)hosted profound and frequent changes in the atmospheric-terres trial-oceanic-climatic system(ATOCS).Previous studies have found contrasting stages for such changes,primarily base...The Ordovician-Silurian transition(OST)hosted profound and frequent changes in the atmospheric-terres trial-oceanic-climatic system(ATOCS).Previous studies have found contrasting stages for such changes,primarily based on hiatus-interrupted sections.However,the dominant driving factors and mechanisms reconciling such frequent changes remain controversial.Mercury isotopes,which undergo both massdependent and mass-independent fractionation,can provide critical insights into the deep-time ATOCSs,especially for those impacted by large igneous provinces(LIPs)events.Here,we build a highresolution multi-proxy record of Hg(concentrations and isotopic compositions)combined with organic carbon isotopes(δ^(13)Corg)and whole-rock geochemical data(including trace elements and phosphorus)from continuous cores in the Yangtze Platform,South China.Our data,combined with reported ones,indicate the occurrence of LIP eruptions against localized volcanism,and four successive,yet contrasting stages of ATOCSs during the OST.Moreover,we identified the coupling between two-pulse LIP magmatism and extreme ATOCSs,each with special pCO_(2),weathering rate,primary productivity,redox condition,climatic mode,and biotic evolution.For stage I,the first pulse of LIP magmatism triggered global warming,enhanced terrestrial weathering,oceanic acidification,eutrophication,anoxia,P recycling,and thereby widespread deposition of black shales.During stage II,the Hirnantian glaciation and oxygenation arose from the intense chemical weathering and black shale deposition of stage I;slashed terrestrial weathering and oceanic oxygenation facilitated CO_(2) accumulation.In stage III,another pulse of LIP magmatism triggered the de-glaciation,and the ATOCS was largely similar to that of stage I.This led to another round of oxygenation and positive d13Corg excursion in stage IV.Compared with the environmental pressure by the peculiar ATOCS of each stage,their transitions might have been more devastating in triggering the prolonged Late Ordovician Mass Extinction(LOME).Moreover,limited biotic recovery was possible in the later portion of stages I and III.The multi-proxy study of continuous strata of the OST provides an excellent framework for better illuminating LIPs’essential role in driving the“roller-coaster”behavior of the ATOCS and thus biotic crisis during the pivotal period of the OST.展开更多
A series of major geological and biological events which altered the evolutionary processes of whole biosphere occurred during the earth history. Establishing a high-resolution stratigraphic framework and timescale is...A series of major geological and biological events which altered the evolutionary processes of whole biosphere occurred during the earth history. Establishing a high-resolution stratigraphic framework and timescale is essential to understand their tempo and causes. High-resolution biostratigraphy remains the most useful approach and forms the basis of dividing the chronostratigraphic system and making the inter-continental and regional correlation. China possesses nearly complete strata from Ediacaran to Quaternary covering wide palaeogeographic regions and containing abundant well-preserved fossils. Traditional biostratigraphy based on sytematic palaeontology of various fossil groups have played an important role in establishing the GSSPs and improving the International and Chinese Stratigraphic Charts. 11 out of 72 establised GSSPs are located in China.Recently, more high-precision geochronology, chemostratigraphy, cyclostrtatigraphy have been applied for stratigraphy and correlation and important advances have been made in some periods. This volume invited Chinese palaeontologists and stratigraphers to summarize the progresses of stratigraphy and timescale from Ediacaran to Quaternary and intercontinental and regional correlation during the last two decades.展开更多
An integrated study of biostratigraphy,microfacies,and stable carbon isotope stratigraphy was carried out on the late Famennian–early Asselian carbonates of the Long’an section in Guangxi,South China.Stable carbon i...An integrated study of biostratigraphy,microfacies,and stable carbon isotope stratigraphy was carried out on the late Famennian–early Asselian carbonates of the Long’an section in Guangxi,South China.Stable carbon isotope studies in the Long’an section have revealed four major positive shifts ofδ13C values in the Carboniferous strata in South China.The first shift occurred in the Siphonodella dasaibaensia zone in the Tournaisian,with an amplitude of 4.19‰.The second shift occurred near the Visean/Serpukhovian boundary,with an amplitude of 2.63‰.The third shift occurred in the Serpukhovian,with an amplitude of 3.95‰.The fourth shift occurred in the Kasimovian,with an amplitude of 3.69‰.Furthermore,there were several brief positiveδ13C shifts during the late Famennian to early Tournaisian.All of these shifts can be well correlated globally,and each corresponds to sea-level regressions in South China and Euro-America,indicating increases in ocean primary productivity and global cooling events.Chronologically,the four major positive excursions ofδ13C,together with several brief positiveδ13C shifts that were observed during the late Famennian to the early Tournaisian,correspond to the well-accepted Glacial I,II,and III events.展开更多
Western Liaoning is a unique region in China that bears diverse types of Jurassic plants, including leaves, fern rhizomes,and wood, providing significant proxy for vegetation and palaeoenvironment reconstruction of th...Western Liaoning is a unique region in China that bears diverse types of Jurassic plants, including leaves, fern rhizomes,and wood, providing significant proxy for vegetation and palaeoenvironment reconstruction of the well-known Yanliao Flora in East Asia. In particular, the silicified wood is very abundant in the fossil Lagerst?tte of the Jurassic Tiaojishan Formation in Beipiao, western Liaoning. Previous and recent systematic investigations documented a high diversity of the Jurassic wood assemblages. These assemblages are dominated by conifers, followed by cycads and ginkgoaleans.In total, about 30 species belonging to 21 genera of fossil wood have been recorded so far, which are represented by Cycadopsida, Ginkgopsida, Coniferopsida, and Gymnospermae incertae sedis. The evolutionary implications of several distinctive fossil wood taxa as well as palaeoclimate implications are summarized based on their anatomical structures and growth ring patterns. This work approaches the vegetation development and evolutionary significances of the wood taxa and their relatives, and provides clues for the further understanding of the diversity of the Jurassic Yanliao Flora in East Asia.展开更多
文摘The non-marine Cretaceous sequences are well developed in the relict basins, i.e. the Luxi basin in the west, and the Jiaolai basin in the east of Shandong Province. The Lower Cretaceous Santai Formation (140 - 136 Ma) in the Luxi basin contains aeolian dune deposits, which were formed under the control by westerly. The Cretaceous strata of the Jiaolai basin are divided into three groups: i.e. in ascending order, the Laiyang, Qingshan and Wangshi groups. New SHRIMP zircon U-Pb radiometric dating data demonstrated six Cretaceous volcanism episodes. The lower part of the Wangshi Group should be assigned to the upper Lower Cretaceous. An Ir anomaly recovered in the lower Jiaozhou Formation suggests that the Cretaceous/Palaeogene boundary would be in the interval between 537.3 - 537.4 m in the borehole JK1. At last the detailed information about the pre-symposium field excursion was introduced.
文摘Clam shrimps are large bivalved branchiopod crustacean. They first occurred in the Devonian, and flourished during the Mesozoic in Asia. Fossil clam shrimps play an important role in the subdivision and correlation of non-marine fossil-bearing strata. The phosphatized carapaces or carapace external/internal moulds are the main objects for taxonomical studies. The delicate ornament and the ontogenetically developing morphological patterns on the growth bands of carapaces are the main fossil taxonomic criteria. While modern clam shrimp taxonomy is based on soft body morphological features and molecular data, which could not be found in the fossil records. This makes it difficult to discuss the fossil and modern clam shrimp phylogenetic relationship. Nowadays scanning electron microscopes are widely available, and can play an important role in investigating clam shrimp carapace morphology which could be common language to integrate fossil and modern taxonomy.
文摘The Lower Cretaceous mixed siliciclastic-carbonate successions of the Boulouha Formation at the type locality in the Dahar escarpment of southern Tunisia have yielded a new discovered assemblage of bivalves which contains Anomia laevigata (Sowerby);Modiolus sp. cf. M. dahuashuensis (Yu et Li);Astarte sp.;and ?Mytilus sp.. The temporal distribution of the Anomia laevigata (Sowerby) and Modiolus sp. cf. M. dahuashuensis (Yu et Li) is limited to the Aptian formations of northeastern China, Japan and Korea, thus we suggest a Hauterivian-Barremian age for the Boulouha Formation. Henceforth, the new biostratigraphic data are used to improve a regional chronostratigraphic correlation between the lower Cretaceous strata of the Saharan Platform domain and those coeval from the Chotts domain.
文摘The evolutionary history of Eupolypods still remains unclear, especially on its diversification scenarios. In recent years, it has been found that approximately 100 million-year-old Myanmar amber provides a unique source of polypod fossils. Different families and numerous sporangia, spores, and scales have been found in Myanmar amber. These discoveries are nevertheless important because they provided the first unequivocal fossil evidence that the diversity of eupolypod ferns was present already in the mid-Cretaceous Myanmar amber forest. This clearly shows that Eupolypods originated before mid-Cretaceous, probably as early as the Early Jurassic, which is consistent with the recent divergence time estimate based on molecular dating.
文摘Normally, trees on the side directly exposed to sunlight will grow faster than the opposing side. This phenomenon is termed plant phototropism. Moreover, palaeomagnetists have revealed that the Junnar Block has never rotated since the Mesozoic. The petrified woods in the Jiangjunmiao area of Qitai County show the positive phototropism direction of SSW220. By compared with the modern normal growth stumps in plain area, which have positive phototropism direction of SSW 219 ± 5, this observation supports the conclusion of palaeomagnetic researchers: the Junggar basin has never rotated since the Late Jurassic.
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).
基金jointly supported by the Geological Survey Programs of the China Geological Survey(Grant Nos.DD20160048-4,12120113053900,12120113053800&1212011085210)the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant Nos.XDB18030502&XDB26010302)+2 种基金the National Natural Science Foundation of China(Grant Nos.41790454,41702032,41688103&41302004)the State Key Laboratory of Palaeobiology and Stratigraphy(NIGPAS,CAS)(Grant No.173124)the Special Fund of the Liaoning Provincial Universities’ Fundamental Scientific Research Project(Grant No.LQN201718)
文摘Two new coniferous wood taxa, Protocedroxylon zhangii sp. nov. and P. zhalantunense sp. nov., are described from the Middle Jurassic Wanbao Formation in Zhalantun City, Inner Mongolia, NE China. The new discovery represents the first record of petrified wood in the Wanbao Formation, and contributes to further understanding the floral composition, especially that of the forest, of the Wanbao Formation. Anatomically, the two new species are characterized by having a mixed type of radial pitting and Abietineentüpfelung. In extant conifers, Abietineentüpfelung is considered to be characteristic of the wood of Pinaceae. The new discovery further indicates that the first occurrence of Abietineentüpfelung in conifer-like wood should be earlier than the Kimmeridgian. The palaeolatitudinal distribution pattern of Protocedroxylon indicates that the genus is a palaeobiogeographically consistent group, which was probably restricted to wetter and cooler temperate climates. In combination with distinct growth rings, the occurrence of Protocedroxylon suggests that a cool temperate and seasonal climate might have prevailed during the sedimentation period of the Wanbao Formation in eastern Inner Mongolia, NE China. Such a view is also in agreement with the palaeoclimatic conditions indicated by the plant megafossils of the Wanbao Formation.
文摘The alternating marine and nonmarine coal-bearing Lower Cretaceous successions are well developed in eastern Heilongjiang, northeastern China, including the Jixi Group in the west and the Longzhaogou Group in the east. The correlation of these two lithostratigraphic groups with the nonmarine Jehol Group is important for dating the exceptionally well-preserved Jehol Biota. The Early Cretaceous marine fossils recovered from eastern Heilongjiang include ammonites, bivalves, radiolarians, foraminifers and dinocysts. During the early Aptian transgression the ammonite fauna entered the Hulin and Mishan areas and the bivalve Aucellina fauna in the Jixi area. This enables correlation of the marine lower part of the Chengzihe Formation of the Jixi Group with the Qihulin Formation of the Longzhaogou Group.
基金projects(Grant nos.41972018,41730317,and 41688103)funded by the National Natural Science Foundation of ChinaStrategic Priority PreResearch Program(B)of the Chinese Academy of Sciences(XDB26000000)China Geological Survey(DD20190009).
文摘The latest Cretaceous strata of the Jiaolai Basin were studied in two scientific cores,including LK-1 drilled by the Institute of Geology,Chinese Academy of Geological Sciences(Li et al.,2018;Li et al.,2020),and JK-1 drilled by the Shandong Institute of the Geological Survey and Institute of Geology,Chinese Academy of Geological Sciences(Xu et al.,2017).However,outcrop sections were poorly studied,and the latest Cretaceous charophyte flora in particular had not previously been adequately documented from outcrops in the Jiaolai area.
基金supported by the National Natural Science Foundation of China(Nos.42172174,41802017,42250104)the National Key R&D Program of China(No.2018YFE0204201)the Fundamental Research Funds for the Central Universities(No.0206-14380168)。
文摘Paleobiogeography investigates geographical distributions of fossil organisms and controlling factors that affect their distributions in geological history,to reveal the macro-evolution and coordinated development of life and the environment.It is a crucial window for understanding the biosphere and the geographical environment.After two centuries of development,paleobiogeographic studies have led to the accumulation of significant amounts of knowledge and data;however,the voluminous outputs present the characteristics of an“isolated island”with a scattered,limited number of authoritative definitions of terminologies and semantic heterogeneity among them.This makes data queries cumbersome,the rate of data reuse low,and data sharing more difficult.A knowledge graph(KG)has the advantage of expressing concepts and their semantic relations,which is an important tool for achieving data organization and fusion,and data mining;further,it is also a key technology for realizing the unrestricted sharing of paleobiogeographic information.Through our efforts over the past two years,a paleobiogeographic KG was developed based on the established construction procedure of the KG,which contains 273 concepts,172 properties,and 47 rules.Meanwhile,the completion of this KG and the construction of a paleobiogeographic platform for display and analysis are now being carried out.
基金supported by the National Key R&D Program of China(Grant No.2022YFF0800200)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant Nos.XDA19050101 and XDB26000000)。
文摘Protolepidodendralean lycopsids are characteristic of morphologically complex leaves.Most taxa of this group are herbaceous and widely distributed in global Devonian sediments,with exceptions of a few members,such as Frenguellia eximia from the Lower Carboniferous of Argentina.In this study,we focus on the morphology of Frenguellia eximia and emend its generic and specific diagnoses,based on new materials from the Upper Devonian Hongguleleng Formation of West Junggar,Xinjiang Uygur Autonomous Region,Northwest China,within the fossil-bearing bed palynologically dated as a latest Famennian age.This is the first finding of Frenguellia eximia out of Gondwana.Frenguellia eximia bears planate leaf with three upward pairs of lateral tips,isomorphic sporophyll to the leaf,and elongated,oval sporangium.Leaf morphology of the members of the Order Protolepidodendrales is summarized and classified into lateral-tip and distal-tip types.Lateral-tip type leaf consists of an obvious main body and several paired lateral tips,whereas distal-tip type leaf shows a petiole and a distal lamina with several planate or three-dimensional segments.Two leaf types probably indicate two independent evolutionary routes of microphylls evolving from simple leaf of prelycopsids during the Devonian period.The new occurrence of Frenguellia eximia further shows paleophytogeographical similarities between West Junggar and northwestern Gondwana.
基金supported by the Strategic Priority Research Program (B) of Chinese Academy of Sciences (Grant No. XDB18000000)the National Natural Science Foundation of China (Grant No. 41672027)
文摘Ediacaran successions occur widely in various depositional facies in South China and yield a series of fossil Lagerst?tten, providing a complete fossil record for the evolution of marine ecosystems after the terminal Cryogenian global glaciation. Carbonate-dominated Ediacaran successions in shallow water facies in South China record a nearly complete δ^(13)C profile that may reflect variations of marine carbon isotopic composition during the Ediacaran Period. The Ediacaran fossils andδ^(13)C profiles from South China permit stratigraphic correlation and subdivision of the Ediacaran strata. Based on biostratigraphic, chemostratigraphic, and geochronometric data from the Ediacaran successions in South China, we propose that the Ediacaran System in China can be subdivided into two series, with three stages in each series. The lower series is characterized by acanthomorphic acritarchs and the upper series by Ediacara-type macrofossils, and the two series are separated by the declining limb of a pronounced δ^(13)C negative excursion(EN3) in the upper Doushantuo Formation. The basal boundary of Stage1 is the same as the basal boundary of Ediacaran System, which has been defined at the base of the cap carbonate unit. Stage 2 represents the first radiation of Ediacaran microscopic organisms, with δ^(13)C feature representing by positive values(EP1). The base of the Stage 2 is placed at the first appearance level of a spiny acritarch species. Stage 3 is characterized by the occurrence of more diverse acritarchs and δ^(13)C feature EP2, with its basal boundary defined by a δ^(13)C negative excursion(EN2) occurring in the middle Doushantuo Formation. The basal boundary of Stage 4 is the same as the upper series. Stage 5 is marked by the occurrence of macrfossils of Miaohe biota, and its lower boundary can be placed at the level where δ^(13)C values transition from positive to negative in MNE, or the first appearance level of macrofossils of the Miaohe biota. Stage 6 is characterized by the occurrences of Ediacara-type Shibantan biota and Gaojiashan biota, with its lower boundary defined by the first appearance level of Conotubus hemiannulatus. The formal establishment of the aforementioned series and stages requires further and more detailed integrative stratigraphic study on the Ediacaran successions in China. Some of the Ediacaran successions in South China have great potential to become global standards in Ediacaran subdivision.
基金supported by the Chinese Academy of Sciences(No.XDB26000000)the CAS Pioneer Hundred Talents Program(No.2018-039)+2 种基金the CAS Open Fund(No.193110)the National Natural Science Foundation of China(Nos.41830323,41930322)the Key Research Program of Frontier Sciences,CAS(No.QYZDY-SSWDQC023)。
文摘Lime mud(i.e.,micrite)is a major component of carbonate deposits.Various mechanisms(biotic versus abiotic)have been proposed for the formation of lime mud in Earth’s history.However,the detailed role that microbes play in the nucleation and subsequent precipitation of micrites remains to be resolved.Herein we undertook a detailed geobiological characterization of laminated lime mudstone from the Middle Triassic Guanling Formation in Yunnan Province,southwestern China.Morphological features,together with previous geobiological investigations,suggest that the laminated lime mudstones represent the former presence of microbial mats.These lime mudstones consist mainly of calcite,dolomite and quartz,with clay minerals and pyrites as subordinate components.In particular,micro-analysis shows copious nano-globules(65–878 nm)and capsule-shaped nano-rods in laminations.These low-Mg calcite nano-globule aggregates are closely associated with mucilaginous biofilms resembling extracellular polymeric substances(EPS).Nano-sized globules coalesce to form semi-euhedral micrite crystals.We suggest that a decaying hydrolytic destruction of the EPS by microbial communities within microbial mat leads to the precipitation of the nano-globules by enhancing alkalinity in local micro-environment.As an intermediate,these nano-globules further aggregate to form micrite crystals possibly through a dissolution-reprecipitation process.
基金supported by the National Natural Science Foundation of China(41873047,41372123)National Science and Technology Major Project(2016ZX05034)Geological Survey Program of China(DD20190085)。
文摘The Ordovician-Silurian transition(OST)hosted profound and frequent changes in the atmospheric-terres trial-oceanic-climatic system(ATOCS).Previous studies have found contrasting stages for such changes,primarily based on hiatus-interrupted sections.However,the dominant driving factors and mechanisms reconciling such frequent changes remain controversial.Mercury isotopes,which undergo both massdependent and mass-independent fractionation,can provide critical insights into the deep-time ATOCSs,especially for those impacted by large igneous provinces(LIPs)events.Here,we build a highresolution multi-proxy record of Hg(concentrations and isotopic compositions)combined with organic carbon isotopes(δ^(13)Corg)and whole-rock geochemical data(including trace elements and phosphorus)from continuous cores in the Yangtze Platform,South China.Our data,combined with reported ones,indicate the occurrence of LIP eruptions against localized volcanism,and four successive,yet contrasting stages of ATOCSs during the OST.Moreover,we identified the coupling between two-pulse LIP magmatism and extreme ATOCSs,each with special pCO_(2),weathering rate,primary productivity,redox condition,climatic mode,and biotic evolution.For stage I,the first pulse of LIP magmatism triggered global warming,enhanced terrestrial weathering,oceanic acidification,eutrophication,anoxia,P recycling,and thereby widespread deposition of black shales.During stage II,the Hirnantian glaciation and oxygenation arose from the intense chemical weathering and black shale deposition of stage I;slashed terrestrial weathering and oceanic oxygenation facilitated CO_(2) accumulation.In stage III,another pulse of LIP magmatism triggered the de-glaciation,and the ATOCS was largely similar to that of stage I.This led to another round of oxygenation and positive d13Corg excursion in stage IV.Compared with the environmental pressure by the peculiar ATOCS of each stage,their transitions might have been more devastating in triggering the prolonged Late Ordovician Mass Extinction(LOME).Moreover,limited biotic recovery was possible in the later portion of stages I and III.The multi-proxy study of continuous strata of the OST provides an excellent framework for better illuminating LIPs’essential role in driving the“roller-coaster”behavior of the ATOCS and thus biotic crisis during the pivotal period of the OST.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41290260, 41521061)the Strategic Priority Research Program of Chinese Academy of Sciences (Grant Nos. XDB26000000, XDB18000000)the Key Research Program of Frontier Sciences from the Chinese Academy of Sciences (Grant No. QYZDY-SSW-DQC023)
文摘A series of major geological and biological events which altered the evolutionary processes of whole biosphere occurred during the earth history. Establishing a high-resolution stratigraphic framework and timescale is essential to understand their tempo and causes. High-resolution biostratigraphy remains the most useful approach and forms the basis of dividing the chronostratigraphic system and making the inter-continental and regional correlation. China possesses nearly complete strata from Ediacaran to Quaternary covering wide palaeogeographic regions and containing abundant well-preserved fossils. Traditional biostratigraphy based on sytematic palaeontology of various fossil groups have played an important role in establishing the GSSPs and improving the International and Chinese Stratigraphic Charts. 11 out of 72 establised GSSPs are located in China.Recently, more high-precision geochronology, chemostratigraphy, cyclostrtatigraphy have been applied for stratigraphy and correlation and important advances have been made in some periods. This volume invited Chinese palaeontologists and stratigraphers to summarize the progresses of stratigraphy and timescale from Ediacaran to Quaternary and intercontinental and regional correlation during the last two decades.
基金This paper has received both technical and financial supports respectively from the National Basic Research Program of China under the State Key Laboratory of Geological Process and Mineral Resources,China University of Geosciences(Wuhan)(No.KZ11K312)the National Natural Science Foundation of China(Grant No.41702366)the Fundamental Research Funds for the Central Universities(No.3142018004)。
文摘An integrated study of biostratigraphy,microfacies,and stable carbon isotope stratigraphy was carried out on the late Famennian–early Asselian carbonates of the Long’an section in Guangxi,South China.Stable carbon isotope studies in the Long’an section have revealed four major positive shifts ofδ13C values in the Carboniferous strata in South China.The first shift occurred in the Siphonodella dasaibaensia zone in the Tournaisian,with an amplitude of 4.19‰.The second shift occurred near the Visean/Serpukhovian boundary,with an amplitude of 2.63‰.The third shift occurred in the Serpukhovian,with an amplitude of 3.95‰.The fourth shift occurred in the Kasimovian,with an amplitude of 3.69‰.Furthermore,there were several brief positiveδ13C shifts during the late Famennian to early Tournaisian.All of these shifts can be well correlated globally,and each corresponds to sea-level regressions in South China and Euro-America,indicating increases in ocean primary productivity and global cooling events.Chronologically,the four major positive excursions ofδ13C,together with several brief positiveδ13C shifts that were observed during the late Famennian to the early Tournaisian,correspond to the well-accepted Glacial I,II,and III events.
基金grants from the Strategic Priority Program(B)of CAS(Grant Nos.XDB 18000000 and26000000)National Natural Sciences Foundation of China(Grant Nos.41709464 and 41688103)+3 种基金State Key Program for Basic Research and Development of Ministry of Science and Technology of China(Grant No.2016YSC0600406)grants from National Natural Sciences Foundation of China(Grant Nos.41772023 and 41402004)State Key Laboratory of Palaeobiology and Stratigraphy(Nanjing Institute of Geology and Palaeontology,CAS)(Grant No.173113)the grant of National Natural Sciences Foundation of China(Grant No.41302004)
文摘Western Liaoning is a unique region in China that bears diverse types of Jurassic plants, including leaves, fern rhizomes,and wood, providing significant proxy for vegetation and palaeoenvironment reconstruction of the well-known Yanliao Flora in East Asia. In particular, the silicified wood is very abundant in the fossil Lagerst?tte of the Jurassic Tiaojishan Formation in Beipiao, western Liaoning. Previous and recent systematic investigations documented a high diversity of the Jurassic wood assemblages. These assemblages are dominated by conifers, followed by cycads and ginkgoaleans.In total, about 30 species belonging to 21 genera of fossil wood have been recorded so far, which are represented by Cycadopsida, Ginkgopsida, Coniferopsida, and Gymnospermae incertae sedis. The evolutionary implications of several distinctive fossil wood taxa as well as palaeoclimate implications are summarized based on their anatomical structures and growth ring patterns. This work approaches the vegetation development and evolutionary significances of the wood taxa and their relatives, and provides clues for the further understanding of the diversity of the Jurassic Yanliao Flora in East Asia.
