Schizolepis daohugouensis sp. nov. is described from the Jurassic sediments of Daohugou flora, from Ningcheng County, Inner Mongolia Autonomous Region, China. The female cone is slender, cylindrical in shape, seed sca...Schizolepis daohugouensis sp. nov. is described from the Jurassic sediments of Daohugou flora, from Ningcheng County, Inner Mongolia Autonomous Region, China. The female cone is slender, cylindrical in shape, seed scale complexes are loosely and helically arranged on the cone axis at intervals of 3-5 mm. The seed scales are bilobed and divided almost from the base; the scales have no evident petiole but an articulation at the region of attachment to the cone axis. Each lobe of the seed scales is oval in shape, widest at the lower middle part; lobes are obtusely pointed with entire margins. Bract scale is fan shaped. Based on the records of Schizolepis, this is the first report of the occurrence of female cone of Schizolepis with the seed scales, the winged seeds and vegetative branches preserved together in the Jurassic deposits. The new discovery provides evidence that confirms the phylogenetic position of Schizolepis to the extant Pinaceae.展开更多
The demarcation of the Lower-Middle Triassic boundary is a disputed problem in global stratigraphic research. Lower-Middle Triassic strata of different types, from platform to basin facies,are well developed in Southw...The demarcation of the Lower-Middle Triassic boundary is a disputed problem in global stratigraphic research. Lower-Middle Triassic strata of different types, from platform to basin facies,are well developed in Southwest China. This is favorable for the study of the Olenekian-Anisian boundary and establishing a stratotype for the Qingyan Stage. Based on research at the Ganheqiao section in Wangmo county and the Qingyan section in Guiyang city, Guizhou province, six conodont zones have been recognized, which can be correlated with those in other regions, in ascending order as follows: 1, Neospathodus cristagalli Interval-Zone; 2, Neospathodus pakistanensis Interval-Zone; 3,Neospathodus waageni Interval-Zone; 4, Neospathodus homeri-N, triangularis Assemblage-Zone; 5,Chiosella timorensis Interval-Zone; and 6, Neogongdolella regalis Range-Zone. An evolutionary series of the Early-Middle Triassic conodont genera Neospathodus-Chiosella-Neogongdolella discovered in the Ganheqiao and Qingyan sections has an intermediate type named Neospathodus qingyanensis that appears between Neospathodus homeri and Chiosella timorensis in the upper part of the Neospathodus homeri-N, triangularis Zone, showing an excellent evolutionary relationship of conodonts near the Lower-Middle Triassic boundary. The Lower-Middle Triassic boundary is located at 1.5 m below the top of the Ziyun Formation, where Chiosella timorensis Zone first appears in the Qingyan section,whereas this boundary is located 0.5 m below the top of the Ziyun Formation, where Chiosella timorensis Zone first appears in the Ganheqiao section. There exists one nearly 6-m thick vitric tuff bed at the bottom of the Xinyuan Formation in the Ganheqiao section, which is usually regarded as a lithologic symbol of the Lower-Middle Triassic boundary in South China. Based on the analysis of high -precision and high-sensitivity Secondary Ion Mass Spectrum data ,the zircon age of this tuff has a weighted mean 206Pb/238U age of 239.0±2.9 Ma (2σ), which is a directly measured zircon U-Pb age of the Lower-Middle Triassic boundary. The Ganheqiao section in Wangmo county can therefore provide an excellent section through the Lower-Middle Triassic because it is continuous, the evolution of the conodonts is distinctive and the regionally stable distributed vitric tuff near the Lower-Middle Triassic boundary can be regarded as a regional key isochronal layer. This section can be regarded not only as a standard section for the establishment of the Qingyan Stage in China, but also as a reference section for the GSSP of the Lower-Middle Triassic boundary.展开更多
The Permian fusulinoidean genus Monodiexodina is widely distributed in east Tethys. The genus might be an important indicator for the northern margin of Gondwana in northwestern China, but this is disputed. Monodiexod...The Permian fusulinoidean genus Monodiexodina is widely distributed in east Tethys. The genus might be an important indicator for the northern margin of Gondwana in northwestern China, but this is disputed. Monodiexodina-bearing areas can be restored as in either northern or southern middle latitudes with a symmetrical distribution between a high latitudinal, cool/cold water climatic realm and a paleotropical, warm water realm. Permian strata bearing Monodiexodina in Karakorum, Muztag Pear, and Buka Daban Pear of the east Kunlun Mountains can be correlated with each other. Faunal analyses and the stratigraphical position of Monodiexodina-bearing strata indicate that both Karakorum, east Kunlun, and the Pamirs were formed in a cool temperate sea area of the northern hemisphere in middle latitudes during the Permian, rather than at the Gondwana margin.展开更多
Scientific research and productive practice for earth history are inseparable from the accurate stratigraphic framework and time framework. Establishing the globally unified, precise and reliable chronostratigraphic s...Scientific research and productive practice for earth history are inseparable from the accurate stratigraphic framework and time framework. Establishing the globally unified, precise and reliable chronostratigraphic series and geological time series is the major goal of the International Commission on Stratigraphy (ICS). Under the leadership of the ICS, the countries around the world have carried out research on the Global Standard Stratotype-section and Points (GSSPs) for the boundaries of chronostratigraphic systems. In the current International Chronostratigraphic Chart (ICC), 65 GSSPs have been erected in the Phanerozoic Eonothem, and one has yet been erected in the Precambrian Eonothem. Based on the progress of research on stratigraphy especially that from its subcommissions, the ICS is constantly revising the ICC, and will publish a new International Stratigraphic Guide in 2020. After continual efforts and broad international cooperation of Chinese stratigraphers, 10 GSSPs within the Phanerozoic Eonothem have been approved and ratified to erect in China by the ICS and IUGS. To establish the standards for strafigraphic division and correlation of China, with the support from the Ministry of Science and Technology, the National Natural Science Foundation of China and the China Geological Survey, Chinese stratigraphers have carried out research on the establishment of Stages in China. A total of 102 stages have been defined in the "Regional Chronostratigraphic Chart of China (geologic time)", in which 59 stages were studied in depth. In 2014, the "Stratigraphic Chart of China" was compiled, with the essential contents as follows: the correlation between international chronostratigraphy and regional chronostratigraphy of China (geologic time), the distributive status of lithostratigraphy, the characteristics of geological ages, the biostratigraphic sequence, the magnetostratigraphy, the geological events and eustatic sea-level change during every geological stage. The "Stratigraphical Guide of China and its Explanation (2014)" was also published. Chinese stratigraphers have paid much attention to stratigraphic research in south China, northeast China, north China and northwest China and they have made great achievements in special research on stratigraphy, based on the 1:1000000, 1:250000, 1:200000 and 1:50000 regional geological survey projects. Manifold new stratigraphic units were discovered and established by the regional geological surveys, which are helpful to improve the regional chronostratigraphic series of China. On the strength of the investigation in coastal and offshore areas, the status of marine strata in China has been expounded. According to the developing situation of international stratigraphy and the characteristics of Chinese stratigraphic work, the contrast relation between regional stratigraphic units of China and GSSPs will be established in the future, which will improve the application value of GSSPs and the standard of regional stratigraphic division and correlation. In addition, the study of stratigraphy of the Precambrian, terrestrial basins and orogenic belts will be strengthened, the Stratigraphic Chart of China will be improved, the typical stratigraphic sections in China will be protected and the applied study of stratigraphy in the fields of oil and gas, solid minerals, etc. will be promoted. On the ground of these actions, stratigraphic research will continue to play a great role in the social and economic development of China.展开更多
基金supported by the China Geological Survey (No. 1212010911047 and 1212010811057)the support from the Ministry Science Technology of the People's Republic of China (Grant 2006FY120300-12)
文摘Schizolepis daohugouensis sp. nov. is described from the Jurassic sediments of Daohugou flora, from Ningcheng County, Inner Mongolia Autonomous Region, China. The female cone is slender, cylindrical in shape, seed scale complexes are loosely and helically arranged on the cone axis at intervals of 3-5 mm. The seed scales are bilobed and divided almost from the base; the scales have no evident petiole but an articulation at the region of attachment to the cone axis. Each lobe of the seed scales is oval in shape, widest at the lower middle part; lobes are obtusely pointed with entire margins. Bract scale is fan shaped. Based on the records of Schizolepis, this is the first report of the occurrence of female cone of Schizolepis with the seed scales, the winged seeds and vegetative branches preserved together in the Jurassic deposits. The new discovery provides evidence that confirms the phylogenetic position of Schizolepis to the extant Pinaceae.
基金support from the Ministry Science Technology of the People's Republic of China (Grant 2006FY120300-12)the China Geological Survey (Grant 1212010811057)
文摘The demarcation of the Lower-Middle Triassic boundary is a disputed problem in global stratigraphic research. Lower-Middle Triassic strata of different types, from platform to basin facies,are well developed in Southwest China. This is favorable for the study of the Olenekian-Anisian boundary and establishing a stratotype for the Qingyan Stage. Based on research at the Ganheqiao section in Wangmo county and the Qingyan section in Guiyang city, Guizhou province, six conodont zones have been recognized, which can be correlated with those in other regions, in ascending order as follows: 1, Neospathodus cristagalli Interval-Zone; 2, Neospathodus pakistanensis Interval-Zone; 3,Neospathodus waageni Interval-Zone; 4, Neospathodus homeri-N, triangularis Assemblage-Zone; 5,Chiosella timorensis Interval-Zone; and 6, Neogongdolella regalis Range-Zone. An evolutionary series of the Early-Middle Triassic conodont genera Neospathodus-Chiosella-Neogongdolella discovered in the Ganheqiao and Qingyan sections has an intermediate type named Neospathodus qingyanensis that appears between Neospathodus homeri and Chiosella timorensis in the upper part of the Neospathodus homeri-N, triangularis Zone, showing an excellent evolutionary relationship of conodonts near the Lower-Middle Triassic boundary. The Lower-Middle Triassic boundary is located at 1.5 m below the top of the Ziyun Formation, where Chiosella timorensis Zone first appears in the Qingyan section,whereas this boundary is located 0.5 m below the top of the Ziyun Formation, where Chiosella timorensis Zone first appears in the Ganheqiao section. There exists one nearly 6-m thick vitric tuff bed at the bottom of the Xinyuan Formation in the Ganheqiao section, which is usually regarded as a lithologic symbol of the Lower-Middle Triassic boundary in South China. Based on the analysis of high -precision and high-sensitivity Secondary Ion Mass Spectrum data ,the zircon age of this tuff has a weighted mean 206Pb/238U age of 239.0±2.9 Ma (2σ), which is a directly measured zircon U-Pb age of the Lower-Middle Triassic boundary. The Ganheqiao section in Wangmo county can therefore provide an excellent section through the Lower-Middle Triassic because it is continuous, the evolution of the conodonts is distinctive and the regionally stable distributed vitric tuff near the Lower-Middle Triassic boundary can be regarded as a regional key isochronal layer. This section can be regarded not only as a standard section for the establishment of the Qingyan Stage in China, but also as a reference section for the GSSP of the Lower-Middle Triassic boundary.
基金support of the National Nature Science Foundation of China(no.:40572018)the China Geological Survey(no.:200313000054,1212010611702,1212010661312,1212010511702,and1212010561605).
文摘The Permian fusulinoidean genus Monodiexodina is widely distributed in east Tethys. The genus might be an important indicator for the northern margin of Gondwana in northwestern China, but this is disputed. Monodiexodina-bearing areas can be restored as in either northern or southern middle latitudes with a symmetrical distribution between a high latitudinal, cool/cold water climatic realm and a paleotropical, warm water realm. Permian strata bearing Monodiexodina in Karakorum, Muztag Pear, and Buka Daban Pear of the east Kunlun Mountains can be correlated with each other. Faunal analyses and the stratigraphical position of Monodiexodina-bearing strata indicate that both Karakorum, east Kunlun, and the Pamirs were formed in a cool temperate sea area of the northern hemisphere in middle latitudes during the Permian, rather than at the Gondwana margin.
基金supported by the Ministry of Science and Technology(Grant No.2015FY310100)the National Natural Science Foundation of China(Grant Nos.41472030)the China Geological Survey(Grant Nos.DD20160120-04,DD20160120-02,DD20160345,1212011120427,12120114026701)
文摘Scientific research and productive practice for earth history are inseparable from the accurate stratigraphic framework and time framework. Establishing the globally unified, precise and reliable chronostratigraphic series and geological time series is the major goal of the International Commission on Stratigraphy (ICS). Under the leadership of the ICS, the countries around the world have carried out research on the Global Standard Stratotype-section and Points (GSSPs) for the boundaries of chronostratigraphic systems. In the current International Chronostratigraphic Chart (ICC), 65 GSSPs have been erected in the Phanerozoic Eonothem, and one has yet been erected in the Precambrian Eonothem. Based on the progress of research on stratigraphy especially that from its subcommissions, the ICS is constantly revising the ICC, and will publish a new International Stratigraphic Guide in 2020. After continual efforts and broad international cooperation of Chinese stratigraphers, 10 GSSPs within the Phanerozoic Eonothem have been approved and ratified to erect in China by the ICS and IUGS. To establish the standards for strafigraphic division and correlation of China, with the support from the Ministry of Science and Technology, the National Natural Science Foundation of China and the China Geological Survey, Chinese stratigraphers have carried out research on the establishment of Stages in China. A total of 102 stages have been defined in the "Regional Chronostratigraphic Chart of China (geologic time)", in which 59 stages were studied in depth. In 2014, the "Stratigraphic Chart of China" was compiled, with the essential contents as follows: the correlation between international chronostratigraphy and regional chronostratigraphy of China (geologic time), the distributive status of lithostratigraphy, the characteristics of geological ages, the biostratigraphic sequence, the magnetostratigraphy, the geological events and eustatic sea-level change during every geological stage. The "Stratigraphical Guide of China and its Explanation (2014)" was also published. Chinese stratigraphers have paid much attention to stratigraphic research in south China, northeast China, north China and northwest China and they have made great achievements in special research on stratigraphy, based on the 1:1000000, 1:250000, 1:200000 and 1:50000 regional geological survey projects. Manifold new stratigraphic units were discovered and established by the regional geological surveys, which are helpful to improve the regional chronostratigraphic series of China. On the strength of the investigation in coastal and offshore areas, the status of marine strata in China has been expounded. According to the developing situation of international stratigraphy and the characteristics of Chinese stratigraphic work, the contrast relation between regional stratigraphic units of China and GSSPs will be established in the future, which will improve the application value of GSSPs and the standard of regional stratigraphic division and correlation. In addition, the study of stratigraphy of the Precambrian, terrestrial basins and orogenic belts will be strengthened, the Stratigraphic Chart of China will be improved, the typical stratigraphic sections in China will be protected and the applied study of stratigraphy in the fields of oil and gas, solid minerals, etc. will be promoted. On the ground of these actions, stratigraphic research will continue to play a great role in the social and economic development of China.