Objective The Yingyangguan Group is widely exposed in the southwestern segment of boundary belt between Yangtze and Cathaysian blocks and is mainly composed of a suit of lower-grade metamorphic marine volcanoclastic-...Objective The Yingyangguan Group is widely exposed in the southwestern segment of boundary belt between Yangtze and Cathaysian blocks and is mainly composed of a suit of lower-grade metamorphic marine volcanoclastic- sedimentary rocks (Zhou Hanwen et al., 2002). Its forming age and petrogenesis are critical for better understanding the orogenic process and relationship of the Yangtze and Cathaysian blocks since the Neoproterozoic. However, few zircon U-Pb ages of samples from the Yingyangguan Group have been reported, which are much debated, such as the metamorphic spilite (819±11 Ma), keratophyre (415.1±2.1 Ma) and ignimbrite (821.3±3.9 Ma) (Tian Yang et al., 2015 and references in). In this study, we focus on the new discovered Early Yanshannian monzogranite and its mafic enclaves from the Yingyangguan Group, and conducted zircon U-Pb dating and in-situ Hf isotopic analyses to constrain their petrogenesis.展开更多
Objective Understanding the dynamics of sediment gravity flows is of great importance to correctly interpret their related deposits. The discovery of supercritical sediment gravity flows provides some new viewpoints ...Objective Understanding the dynamics of sediment gravity flows is of great importance to correctly interpret their related deposits. The discovery of supercritical sediment gravity flows provides some new viewpoints for the explanation of controversial sediment gravity flow deposits. However, the dynamics, formation, evolution processes of supercritical sediment gravity flows and their recognition criteria from their associated deposits are still worldwide controversial. The supercritical hyperpycnal flow deposits recognized in the upper part of Early Cretaceous Lingshandao Formation provide a rare opporttmity to understand their sedimentary characteristics. This work is aimed at documenting the typical sedimentary structures associated with the supercritical hyperpycnal flow, and discussing the vertical stacking and its relationship with flow evolution.展开更多
In the early days of the founding of the People’s Republic of China,in order to restore the national economy as soon as possible,the Communist Party of China carried out maintenance and repairs on the railways that c...In the early days of the founding of the People’s Republic of China,in order to restore the national economy as soon as possible,the Communist Party of China carried out maintenance and repairs on the railways that caused serious damage to transportation tasks through war-torn smoke,and carried out large-scale railway construction.However,in the course of operation,railway safety accidents occur frequently due to outdated equipment,low quality of staff,lack of rules and regulations,vandalism,and various natural disasters.In the face of severe conditions,the railway authorities summed up the accidents and learned the safety of the railways,so that the railway transportation industry,which started after the founding of the country,was gradually on the right track,and laid a solid foundation for the safe development of the railway industry.展开更多
Two well-preserved fossil dragonflies from the Late Mesozoic Yixian Formation, Liaoning Province, China are described and assigned to a new genus, Sopholibellula gen. nov. in Araripelibellulidae Bechly, 1996, closely ...Two well-preserved fossil dragonflies from the Late Mesozoic Yixian Formation, Liaoning Province, China are described and assigned to a new genus, Sopholibellula gen. nov. in Araripelibellulidae Bechly, 1996, closely related to the type genus Araripelibellula. This new genus differs from AraripelibeUula in the following characters: origins of RP and MA distinctly separated at arculus in both pairs of wings; anal loop wider and shorter, with Y-shaped veins inside; MA and IR2 not zigzag; several small intercalary veins present in the postdiscoidal area of hindwing; cells smaller and much more dense, especially in the apex and hind margin; bigger in size. Structures, including head, abdomen and parts of legs, were first described in details of this family.展开更多
Four Changes in World EconomyFirst,a new round of global economic growth is under way.In 2000,oil pricerose rapidly,stoek markets and exchange rates remained volatile and interestrates went up.All these disadvantages ...Four Changes in World EconomyFirst,a new round of global economic growth is under way.In 2000,oil pricerose rapidly,stoek markets and exchange rates remained volatile and interestrates went up.All these disadvantages did not undermine the foundations of worldeconomy,and the average growth rate of global gross domestic product(GDP)展开更多
A new Eocene catostomid genus and species,Plesiomyxocyprinus arratiae, is described from Huadian, Jilin Province, northeastern China. The materials include a nearly complete skeleton, dozens of pharyngeal bones with t...A new Eocene catostomid genus and species,Plesiomyxocyprinus arratiae, is described from Huadian, Jilin Province, northeastern China. The materials include a nearly complete skeleton, dozens of pharyngeal bones with teeth, and a number of disarticulated bones. The new articulated specimen is large-sized and deep-bodied, with an estimated standard length of ca. 300 mm and body depth of 156 mm or about half of its standard length. The assignment of the fish to the Catostomidae is based on its falciform pharyngeal bone with one row of numerous (more than 50) compressed teeth, and the bone is much smaller than in cyprinids, especially given the size of the fish. The new fish distinguishes itself from all known catostomids (both extinct and extant) in its long anal fin with four unbranched and 17-18 branched rays, and its extremely short caudal peduncle that is only about one fourth of its depth. Plesiomyxocyprinus arratiae resembles the Eocene-Oligocene transpacific-distributed Amyzon in many general skeletal characters. However, it shows a few characters uniquely shared with the Recent catostomid Myxocyprinus asiaticus. Those include a very long dorsal fin with about 50 branched fin rays, the end of dorsal fin rays being close to the caudal fin base, and anal rays stretching posteriorly beyond the base of caudal fin. It is the first fossil catostomid that shows a close relationship to the endemic Myxocyprinus now living in the Yangtze River and Minjiang River, China. The discovery of Plesiomyxocyprinus arratiae, along with two previously described possible catostomid genera Jianghanichthys and Vasnetzovia, may indicate that the divergence of the Catostomidae started much earlier, in the middle Eocene or earlier, on the western side of the Pacific than on its eastern side.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
Here we describe Huashancyprinus robustispinus,gen.et sp.nov,a fossil cyprinin fish from the Oligocene of Ningming Ba-sin,Guangxi,South China.It differs from all other cyprinin fishes in the following apomorphic chara...Here we describe Huashancyprinus robustispinus,gen.et sp.nov,a fossil cyprinin fish from the Oligocene of Ningming Ba-sin,Guangxi,South China.It differs from all other cyprinin fishes in the following apomorphic characters:extremely robust last unbranched dorsal and anal fin rays with very fine serrations along posterior edge,the crowns of pharyngeal teeth A2 and A3 with a number of deep grooves on the lateral wall,rather large A3,and relatively deep infraorbital 2.Among the members of the Tribe Cyprinini sensu stricto,it mostly resembles the extant genus Cyprinus,particularly to species Cyprinus micristius and C.fuxianensis,which are restricted to Yunnan,southwestern China.The discovery of the cyprinin Huashancyprinus from southern China,along with the previously known late Eocene Cyprinus maomingensis,indicates an early branching of the Cyprininae(Cyprinidae) in this area.展开更多
A single set of 5 bird tracks was discovered in the Tianjialou Formation (Barremian-Albian) of Junan County, Shandong Province, China. After careful study we infer that it is a new type of bird tracks, and a new ichno...A single set of 5 bird tracks was discovered in the Tianjialou Formation (Barremian-Albian) of Junan County, Shandong Province, China. After careful study we infer that it is a new type of bird tracks, and a new ichnoge- nus was erected and the name Shandongornipes was given. The characteristics of the new bird track are as follows: Moderately large tetradactyl footprints with well-developed hallux impression. Track width (about 5.8 cm) almost equal to track length (excluding hallux); total length of track (in- cluding hallux) 8.7 cm. The digit impressions are slender, with distal ends showing long sharp claw marks. Hallux pos- teriorly-directed, and hallux impressions well-developed. Digits II, III and IV point anteriorly, exhibiting mesaxonic asymmetry: divarication angle between II and III much lar- ger than that of III and IV, the former ranging from 91° to 118°, and the latter less than 30°. Divarication between digits II and IV ranging from 128° to 142°. Without web structures. Digital pads recognizable, usually at least three in digits III and IV, but sometimes only two due to preservation. The trackway shows slight positive (inward) rotation of feet. The bird tracks occur in association with abundant dinosaur tracks, and are believed to have formed in flood plain environments.展开更多
基金financially supported by the China Geological Survey(grants No.12120113063200 and DD20160035-1)
文摘Objective The Yingyangguan Group is widely exposed in the southwestern segment of boundary belt between Yangtze and Cathaysian blocks and is mainly composed of a suit of lower-grade metamorphic marine volcanoclastic- sedimentary rocks (Zhou Hanwen et al., 2002). Its forming age and petrogenesis are critical for better understanding the orogenic process and relationship of the Yangtze and Cathaysian blocks since the Neoproterozoic. However, few zircon U-Pb ages of samples from the Yingyangguan Group have been reported, which are much debated, such as the metamorphic spilite (819±11 Ma), keratophyre (415.1±2.1 Ma) and ignimbrite (821.3±3.9 Ma) (Tian Yang et al., 2015 and references in). In this study, we focus on the new discovered Early Yanshannian monzogranite and its mafic enclaves from the Yingyangguan Group, and conducted zircon U-Pb dating and in-situ Hf isotopic analyses to constrain their petrogenesis.
基金the National Science Foundation of China (grant No.U1262203)the National Science and Technology Special Grant (grant No.2016ZX05006-007) for their financial support
文摘Objective Understanding the dynamics of sediment gravity flows is of great importance to correctly interpret their related deposits. The discovery of supercritical sediment gravity flows provides some new viewpoints for the explanation of controversial sediment gravity flow deposits. However, the dynamics, formation, evolution processes of supercritical sediment gravity flows and their recognition criteria from their associated deposits are still worldwide controversial. The supercritical hyperpycnal flow deposits recognized in the upper part of Early Cretaceous Lingshandao Formation provide a rare opporttmity to understand their sedimentary characteristics. This work is aimed at documenting the typical sedimentary structures associated with the supercritical hyperpycnal flow, and discussing the vertical stacking and its relationship with flow evolution.
文摘In the early days of the founding of the People’s Republic of China,in order to restore the national economy as soon as possible,the Communist Party of China carried out maintenance and repairs on the railways that caused serious damage to transportation tasks through war-torn smoke,and carried out large-scale railway construction.However,in the course of operation,railway safety accidents occur frequently due to outdated equipment,low quality of staff,lack of rules and regulations,vandalism,and various natural disasters.In the face of severe conditions,the railway authorities summed up the accidents and learned the safety of the railways,so that the railway transportation industry,which started after the founding of the country,was gradually on the right track,and laid a solid foundation for the safe development of the railway industry.
基金The research was supported by the National Natural Science Foundation of China (grants 30025006, 30370184, and 30430100)State Key Laboratory of Biocontrol, Sun Yat-Sen University (2003-01)+2 种基金Beijing Natural Science Foundation (5032003)Scientific Research Key Program (KZ200410028013) RCQJ Project of the Beijing Municipal Commission of Education.
文摘Two well-preserved fossil dragonflies from the Late Mesozoic Yixian Formation, Liaoning Province, China are described and assigned to a new genus, Sopholibellula gen. nov. in Araripelibellulidae Bechly, 1996, closely related to the type genus Araripelibellula. This new genus differs from AraripelibeUula in the following characters: origins of RP and MA distinctly separated at arculus in both pairs of wings; anal loop wider and shorter, with Y-shaped veins inside; MA and IR2 not zigzag; several small intercalary veins present in the postdiscoidal area of hindwing; cells smaller and much more dense, especially in the apex and hind margin; bigger in size. Structures, including head, abdomen and parts of legs, were first described in details of this family.
文摘Four Changes in World EconomyFirst,a new round of global economic growth is under way.In 2000,oil pricerose rapidly,stoek markets and exchange rates remained volatile and interestrates went up.All these disadvantages did not undermine the foundations of worldeconomy,and the average growth rate of global gross domestic product(GDP)
基金Supported by National Natural Science Foundation of China (Grant No. 40432003, J0630965)Cypriniformes Tree of Life under the U.S. National Science Foundation to R. Mayden (Grant No. EF0431326)Ecocarp Project (European Commission, INCO-DEV Programme) (Grant No. ICA4-CT-2001-10024)
文摘A new Eocene catostomid genus and species,Plesiomyxocyprinus arratiae, is described from Huadian, Jilin Province, northeastern China. The materials include a nearly complete skeleton, dozens of pharyngeal bones with teeth, and a number of disarticulated bones. The new articulated specimen is large-sized and deep-bodied, with an estimated standard length of ca. 300 mm and body depth of 156 mm or about half of its standard length. The assignment of the fish to the Catostomidae is based on its falciform pharyngeal bone with one row of numerous (more than 50) compressed teeth, and the bone is much smaller than in cyprinids, especially given the size of the fish. The new fish distinguishes itself from all known catostomids (both extinct and extant) in its long anal fin with four unbranched and 17-18 branched rays, and its extremely short caudal peduncle that is only about one fourth of its depth. Plesiomyxocyprinus arratiae resembles the Eocene-Oligocene transpacific-distributed Amyzon in many general skeletal characters. However, it shows a few characters uniquely shared with the Recent catostomid Myxocyprinus asiaticus. Those include a very long dorsal fin with about 50 branched fin rays, the end of dorsal fin rays being close to the caudal fin base, and anal rays stretching posteriorly beyond the base of caudal fin. It is the first fossil catostomid that shows a close relationship to the endemic Myxocyprinus now living in the Yangtze River and Minjiang River, China. The discovery of Plesiomyxocyprinus arratiae, along with two previously described possible catostomid genera Jianghanichthys and Vasnetzovia, may indicate that the divergence of the Catostomidae started much earlier, in the middle Eocene or earlier, on the western side of the Pacific than on its eastern side.
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 National Natural Science Foundation of China(Grant Nos.40432003 and 40662001)State Key Laboratory of Palaeobiology and Stratigraphy(Nanjing Institute of Geology and Palaeontology,CAS)(Grant No.063106)Cypriniformes Tree of life under the U.S.National Science Foundation to R.Mayden(Grant No. EFO431326),and the Culture Department of Guangxi Zhuang Autonomous Region
文摘Here we describe Huashancyprinus robustispinus,gen.et sp.nov,a fossil cyprinin fish from the Oligocene of Ningming Ba-sin,Guangxi,South China.It differs from all other cyprinin fishes in the following apomorphic characters:extremely robust last unbranched dorsal and anal fin rays with very fine serrations along posterior edge,the crowns of pharyngeal teeth A2 and A3 with a number of deep grooves on the lateral wall,rather large A3,and relatively deep infraorbital 2.Among the members of the Tribe Cyprinini sensu stricto,it mostly resembles the extant genus Cyprinus,particularly to species Cyprinus micristius and C.fuxianensis,which are restricted to Yunnan,southwestern China.The discovery of the cyprinin Huashancyprinus from southern China,along with the previously known late Eocene Cyprinus maomingensis,indicates an early branching of the Cyprininae(Cyprinidae) in this area.
文摘A single set of 5 bird tracks was discovered in the Tianjialou Formation (Barremian-Albian) of Junan County, Shandong Province, China. After careful study we infer that it is a new type of bird tracks, and a new ichnoge- nus was erected and the name Shandongornipes was given. The characteristics of the new bird track are as follows: Moderately large tetradactyl footprints with well-developed hallux impression. Track width (about 5.8 cm) almost equal to track length (excluding hallux); total length of track (in- cluding hallux) 8.7 cm. The digit impressions are slender, with distal ends showing long sharp claw marks. Hallux pos- teriorly-directed, and hallux impressions well-developed. Digits II, III and IV point anteriorly, exhibiting mesaxonic asymmetry: divarication angle between II and III much lar- ger than that of III and IV, the former ranging from 91° to 118°, and the latter less than 30°. Divarication between digits II and IV ranging from 128° to 142°. Without web structures. Digital pads recognizable, usually at least three in digits III and IV, but sometimes only two due to preservation. The trackway shows slight positive (inward) rotation of feet. The bird tracks occur in association with abundant dinosaur tracks, and are believed to have formed in flood plain environments.