1.Objectives Shaanxilithes is one of the potential biostratigraphic markers for the definition and correlation of terminal Ediacaran strata.They have been found in terminal Ediacaran siliciclastic successions from Sha...1.Objectives Shaanxilithes is one of the potential biostratigraphic markers for the definition and correlation of terminal Ediacaran strata.They have been found in terminal Ediacaran siliciclastic successions from Shaanxi Province(Meyer M et al.,2012),Ningxia Hui Autonomous Region(Shen B et al.,2007),Qinghai Province(Shen B et al.,2007),Guizhou Province(Hua H et al.,2004),Yunnan Province(Zhang ZL et al.,2015)in China,and India(Tarhan LG et al.,2014),Siberia(Cai YP and Hua H,2011)and Namibia(Darroch S et al.,2016).However,these fossils have never been found in the carbonate dominant Dengying Formation in the Yangtze Gorges area.展开更多
Objective Geological records of Earth history in the Hadean(>4.0 Ga)are critical for understanding the earliest evolution of the planet’s continental crust.Unfortunately,investigation of such proto-continental cru...Objective Geological records of Earth history in the Hadean(>4.0 Ga)are critical for understanding the earliest evolution of the planet’s continental crust.Unfortunately,investigation of such proto-continental crust,including its formation mechanism and evolution,has been extremely limited due to the scarcity of Hadean terranes,because most ancient crustal records have been destroyed during subsequent geological processes.展开更多
Jurassic continental strata are widely distributed in the Changdu area of eastern Tibet,but very few dinosaur footprints have been reported.Abundant sauropod,ornithopod and theropod footprints preserved in the Wenda s...Jurassic continental strata are widely distributed in the Changdu area of eastern Tibet,but very few dinosaur footprints have been reported.Abundant sauropod,ornithopod and theropod footprints preserved in the Wenda site have been found during the recent geological surveys.This is a novel assemblage of the Middle Jurassic dinosaur footprints.These footprint fossils provide a key insight into the members of dinosaur faunas,and the behavior of the trackmakers.Here,the newly discovery small theropod footprints,which are identified as Wildeichnus isp.,are discussed.The analysis of two trackways suggest that these two trackmakers(with a hip height of approx.35 cm,and a body length of approx.1 m)were moving slowly,with an estimated speed of 0.82 and 0.57 m/s,respectively.It is unusual for small theropods to move so slowly,and the present study supports the view that Wildeichnus had a global distribution,but the trackmaker of Wildeichnus is not interpreted as a juvenile Grallator.展开更多
The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figur...The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figured, including a new species named Wangshangkia jiwozhaiensis sp. nov. The ostracod fauna in the Jiwozhai patch reef represents a Givetian age. The ostracod assemblage belongs to the smooth-podocopid association, which is also ecologically equivalent to the Eifelian Mega-Assemblage Ⅲ. This association is indicative of shallow open-marine environments. The Jiwozhai patch reef fauna is primarily comprised of suspension feeders, including filter-feeding ostracods, corals, brachiopods and bryozoans. Ostracods from the Jiwozhai patch reef were compared to the ostracod faunas from Laurentia-Baltica at generic level, which reveals limited faunal exchanges between South China and Laurentia-Baltica during the Middle Devonian.展开更多
This study provides an overview and discussion of controls on the distribution of organic reefs during the Early Ordovican Period, in the Yangtze Platform, a region of epicontinental sedimentary rocks in South China. ...This study provides an overview and discussion of controls on the distribution of organic reefs during the Early Ordovican Period, in the Yangtze Platform, a region of epicontinental sedimentary rocks in South China. The Yangtze Platform was located in low latitudes during the Early Ordovician and recorded rich and diverse reefs through that time. During the late Tremadocian Epoch, dolomitic and stratiform stromatolites were common in supratidal to intertidal zones of the western Yangtze Platform, while columnar stromatolites formed in deeper waters of the eastern Yangtze Platform. Skeletal-dominated reefs occurred in upper subtidal settings of the central Yangtze Platform. A transition from microbial-dominated to metazoan-dominated reefs with shallowing-upward cycles was evident, indicating that the composition of the main reef-builders was driven mainly by water depth.Increasing metazoan competition during the Great Ordovician Biodiversification Event reduced the abundance of microbial reefs. Sufficient nutrient supply is interpreted to have promoted development of skeletal-dominated reefs locally in shallow settings in the central Yangtze Platform, especially represented by the expansion of abundant solitary fossils of lithistid sponges and Calathium. High salinity environmental settings facilitated the bloom of stromatolites in near-shore locations. Low oxygen content in deep subtidal settings may have led to the absence of skeletal reefs in these habitats, so the mass occurrences of stromatolites was located in the shallower-water central and eastern platform. No keratose sponge-bearing stromatolite can be confirmed across the platform during this interval.展开更多
基金This work was supported by the National Natural Science Foundation of China(41802206,41530104,41303026)Open Fund of State Key Laboratory of Biogeology and Environmental Geology(GBL201709)project of China Geological Survey(DD20190811).
文摘1.Objectives Shaanxilithes is one of the potential biostratigraphic markers for the definition and correlation of terminal Ediacaran strata.They have been found in terminal Ediacaran siliciclastic successions from Shaanxi Province(Meyer M et al.,2012),Ningxia Hui Autonomous Region(Shen B et al.,2007),Qinghai Province(Shen B et al.,2007),Guizhou Province(Hua H et al.,2004),Yunnan Province(Zhang ZL et al.,2015)in China,and India(Tarhan LG et al.,2014),Siberia(Cai YP and Hua H,2011)and Namibia(Darroch S et al.,2016).However,these fossils have never been found in the carbonate dominant Dengying Formation in the Yangtze Gorges area.
基金financially supported by National Science Foundation of China(Grant Nos.41303026)the funded project of Hubei Key Laboratory of Paleontology and Geological Environment Evolution(Grant No.PEL-202010)China Geological Survey(Grant No.DD20190050)。
文摘Objective Geological records of Earth history in the Hadean(>4.0 Ga)are critical for understanding the earliest evolution of the planet’s continental crust.Unfortunately,investigation of such proto-continental crust,including its formation mechanism and evolution,has been extremely limited due to the scarcity of Hadean terranes,because most ancient crustal records have been destroyed during subsequent geological processes.
基金supported by the National Natural Science Foundation of China(No.92055212)the China Geological Survey(Nos.DD20242327 and DD20230006)+3 种基金the Open Foundation of the State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan(No.GPMR202105)the Open Foundation of the Hubei Key Laboratory of Paleontology and Geological Environment Evolution,Wuhan Center,China Geological Survey(No.PEL-202203)supported by the Chengdu Bureau of State Natural Resources Supervision,Department of Natural Resources of Tibet Autonomous Region,Changdu Natural Resources BureauRitong Town People’s Government.
文摘Jurassic continental strata are widely distributed in the Changdu area of eastern Tibet,but very few dinosaur footprints have been reported.Abundant sauropod,ornithopod and theropod footprints preserved in the Wenda site have been found during the recent geological surveys.This is a novel assemblage of the Middle Jurassic dinosaur footprints.These footprint fossils provide a key insight into the members of dinosaur faunas,and the behavior of the trackmakers.Here,the newly discovery small theropod footprints,which are identified as Wildeichnus isp.,are discussed.The analysis of two trackways suggest that these two trackmakers(with a hip height of approx.35 cm,and a body length of approx.1 m)were moving slowly,with an estimated speed of 0.82 and 0.57 m/s,respectively.It is unusual for small theropods to move so slowly,and the present study supports the view that Wildeichnus had a global distribution,but the trackmaker of Wildeichnus is not interpreted as a juvenile Grallator.
基金financially supported by the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2023324)the Hubei Key Laboratory of Paleontology and Geological Environment Evolution,Wuhan Center of China Geological Survey(PEL-202301)+1 种基金the Science and Technology Fundamental Resources Investigation Program(Grand No.2023FY100900)the Natural Science Foundation of China(Grant No.41802018).
文摘The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figured, including a new species named Wangshangkia jiwozhaiensis sp. nov. The ostracod fauna in the Jiwozhai patch reef represents a Givetian age. The ostracod assemblage belongs to the smooth-podocopid association, which is also ecologically equivalent to the Eifelian Mega-Assemblage Ⅲ. This association is indicative of shallow open-marine environments. The Jiwozhai patch reef fauna is primarily comprised of suspension feeders, including filter-feeding ostracods, corals, brachiopods and bryozoans. Ostracods from the Jiwozhai patch reef were compared to the ostracod faunas from Laurentia-Baltica at generic level, which reveals limited faunal exchanges between South China and Laurentia-Baltica during the Middle Devonian.
基金supported by the China Geological Survey Project (Grant No.DD2019823)the Natural Science Foundation of China (Grant No. 41702003)+1 种基金the Youth Innovation Promotion Association of CAS (2019310)the special fund for strategic pilot technology Chinese Academy of Sciences(Type B, Grant No. XDB26000000)。
文摘This study provides an overview and discussion of controls on the distribution of organic reefs during the Early Ordovican Period, in the Yangtze Platform, a region of epicontinental sedimentary rocks in South China. The Yangtze Platform was located in low latitudes during the Early Ordovician and recorded rich and diverse reefs through that time. During the late Tremadocian Epoch, dolomitic and stratiform stromatolites were common in supratidal to intertidal zones of the western Yangtze Platform, while columnar stromatolites formed in deeper waters of the eastern Yangtze Platform. Skeletal-dominated reefs occurred in upper subtidal settings of the central Yangtze Platform. A transition from microbial-dominated to metazoan-dominated reefs with shallowing-upward cycles was evident, indicating that the composition of the main reef-builders was driven mainly by water depth.Increasing metazoan competition during the Great Ordovician Biodiversification Event reduced the abundance of microbial reefs. Sufficient nutrient supply is interpreted to have promoted development of skeletal-dominated reefs locally in shallow settings in the central Yangtze Platform, especially represented by the expansion of abundant solitary fossils of lithistid sponges and Calathium. High salinity environmental settings facilitated the bloom of stromatolites in near-shore locations. Low oxygen content in deep subtidal settings may have led to the absence of skeletal reefs in these habitats, so the mass occurrences of stromatolites was located in the shallower-water central and eastern platform. No keratose sponge-bearing stromatolite can be confirmed across the platform during this interval.
