The terrigenously-dominated marine shales which were deposited in the lower Eocene Pinghu Formation were thought to be a potential source rock in the Xihu Depression of the East China Sea Shelf Basin.However,the excep...The terrigenously-dominated marine shales which were deposited in the lower Eocene Pinghu Formation were thought to be a potential source rock in the Xihu Depression of the East China Sea Shelf Basin.However,the exceptionally high total organic carbon content(TOC,>6%on average)of the tidal sand ridge samples was not compatible with their sedimentary environment,indicating coal-bearing sedimentary debris may have been transferred from the coast to the ocean.In this study,new sights into the origins and supply of organic materials in the coastal environment were proposed in the neritic organic matter of the Eocene Pinghu Formation.A discriminant model was developed using plynofacies analysis data to pinpoint the source of organic materials in marine source rocks.The discrimination results suggested that marine mudstones were associated with tidal flat mudstones rather than deltaic ones.The biomarker characteristics of mudstones deposited in various environments support this assertion,indicating that the supply of plant materials in tidal flats is the primary organic matter source for the marine environment.The organic matter abundance was elevated in tidal flats due to their superior preservation conditions.Additionally,the lithological assemblage of tidal flats suggests that tidal currents can scour marshes and then transport dispersed terrigenous organic materials to neritic areas.These findings indicate that coal-bearing sedimentary debris was likely transferred from the coast to the ocean,and tidal currents are thought to be the dominant mechanism driving organic matter from the tidal to the marine environment.展开更多
INTRODUCTIONThe coast zone is the area where most human activities take place and where the highest economic benefit is produced. The knowledge of the distribution and variation of primary production provides the base...INTRODUCTIONThe coast zone is the area where most human activities take place and where the highest economic benefit is produced. The knowledge of the distribution and variation of primary production provides the bases as reference helping the marine exploitation and management.展开更多
There were different biogeographical tintinnids in the oceans. Knowledge of their distribution pattern and mixing was important to the understanding of ecosystem functions. Yellow Sea(YS) and Bohai Sea(BS) were semi-e...There were different biogeographical tintinnids in the oceans. Knowledge of their distribution pattern and mixing was important to the understanding of ecosystem functions. Yellow Sea(YS) and Bohai Sea(BS) were semi-enclosed seas influenced by warm water intrusion and YS cold bottom water. The occurrence of tintinnids in YS and BS during two cruises(summer and winter) were investigated to find out: i) whether warm-water tintinnids appeared in YS and BS; ii) whether boreal tintinnids appeared in high summer; iii) the core area of neritic tintinnids and iv) how these different biogeographical tintinnids mixed. Our results showed that tintinnid community was dominated by neritic tintinnid. We confirmed the occurrence of warm-water tintinnids in summer and winter. In summer, they intruded into BS and mainly distributed in the upper 20 m where Yellow Sea Surface Warm Water(YSSWW) developed. In winter, they were limited in the surface water of central deep region(bottom depth >50 m) of YS where were affected by Yellow Sea Warm Water(YSWW). Boreal tintinnids occurred in YS in high summer(August) and in winter, while they were not observed in BS. In summer, the highest abundance of boreal tintinnids occurred in Yellow Sea Bottom Cold Water, indicating the presence of an oversummering stock. In winter, they were concentrated in the north of YSWW. Vertically, neritic tintinnids abundance was high in the bottom layers. Horizontally, high neritic tintinnids abundance in bottom layers occurred along the 50 m isobath coinciding with the position of front systems. Front systems were the core distribution area of neritic tintinnids. High abundance areas of warm-water and boreal tintinnids were clearly separated vertically in summer, and horizontally in winter. High abundance of neritic tintinnids rarely overlapped with that of warm-water or boreal tintinnids.展开更多
Grain size analysis, X ray diffraction analysis and biostratigraphy analysis of the structure, composition and formation conditions of the neritic silty clay facies sediments extensively distributed in the central par...Grain size analysis, X ray diffraction analysis and biostratigraphy analysis of the structure, composition and formation conditions of the neritic silty clay facies sediments extensively distributed in the central part of the South Yellow Sea showed that the sediments were composed of more than 70% clay, less than 30% silt, had very little or no sand, and were characterized by homogenous texture, soapy feeling, high plasticity, light green gray color and elliptical distribution being about 3 m thick in the center, being thinner towards the margin and finally thinning out. These shelf cyclonic eddy environment sediments formed a sedimentary facies different from that of the sediments in the neighbouring area and revealed the particular sediment dynamic pattern in the environment.展开更多
Mixed deposition is a sedimentary phenomenon of special significance to the tectonic movement, material supply, sea level change, andpaleoclimate of the sedimentary environment. The sediments of the Late Carboniferous...Mixed deposition is a sedimentary phenomenon of special significance to the tectonic movement, material supply, sea level change, andpaleoclimate of the sedimentary environment. The sediments of the Late Carboniferous-Early Permian System in the North China Craton, whichare composed of clastic rock and limestone, are mixed clastic-platform carbonate sediments in the epicontinental sea. Based on the geologicaland well logging data of nearly 100 exploratory wells and hundreds of development wells in the region, the lithologic association and cyclefeatures of the Upper Carboniferous-Lower Permian were determined. From this data, the Benxi Formation and the Taiyuan Formation of theDaniudi Gasfield are considered to belong to a mixed clastic coastline-carbonate platform sedimentary system and coastal plain sedimentarysystem in the epicontinental sea. Based on the six transgressions and regressions during the Late Carboniferous-Early Permian epochs in theregion, combined with the regional evolution history, this study analyzed the sedimentary evolution history of the Daniudi Gasfield from the LateCarboniferous to the Early Permian.展开更多
As an important component of microzooplankton,ciliates play a key role in matter cycling and energy fow in marine planktonic ecosystems.Studies of planktonic ciliate have been extensive in the South China Sea(SCS)over...As an important component of microzooplankton,ciliates play a key role in matter cycling and energy fow in marine planktonic ecosystems.Studies of planktonic ciliate have been extensive in the South China Sea(SCS)over the last 20 years.Here,we summarize the recent progress on the diversity and distribution of this group in the SCS.This includes that in:(1)the waters covering the intertidal zone of the northern SCS,most studies have focused on taxonomy,with 71 species collected,identifed,and described(with~40%new species);(2)neritic waters distribution patterns have been examined at a regional scale,with ciliates displaying signifcant spatial variations and seasonal dynamics;(3)in oceanic waters,there has been a focus on ciliate distribution in north,centre,and south regions,where mesoscale physical processes play roles in controlling distributions,and noticeable vertical variations occur.More generally,some studies examine the infuences of environment variables on ciliates,and indicate that chlorophyll a concentration is commonly positively correlated with ciliates abundance.In addition,some signifcant fndings are summarized,the limitations of past studies are considered,and recommendations are made for future work on planktonic ciliates in SCS.展开更多
基金China Postdoctoral Science Foundation under contract No.2021M703619。
文摘The terrigenously-dominated marine shales which were deposited in the lower Eocene Pinghu Formation were thought to be a potential source rock in the Xihu Depression of the East China Sea Shelf Basin.However,the exceptionally high total organic carbon content(TOC,>6%on average)of the tidal sand ridge samples was not compatible with their sedimentary environment,indicating coal-bearing sedimentary debris may have been transferred from the coast to the ocean.In this study,new sights into the origins and supply of organic materials in the coastal environment were proposed in the neritic organic matter of the Eocene Pinghu Formation.A discriminant model was developed using plynofacies analysis data to pinpoint the source of organic materials in marine source rocks.The discrimination results suggested that marine mudstones were associated with tidal flat mudstones rather than deltaic ones.The biomarker characteristics of mudstones deposited in various environments support this assertion,indicating that the supply of plant materials in tidal flats is the primary organic matter source for the marine environment.The organic matter abundance was elevated in tidal flats due to their superior preservation conditions.Additionally,the lithological assemblage of tidal flats suggests that tidal currents can scour marshes and then transport dispersed terrigenous organic materials to neritic areas.These findings indicate that coal-bearing sedimentary debris was likely transferred from the coast to the ocean,and tidal currents are thought to be the dominant mechanism driving organic matter from the tidal to the marine environment.
文摘INTRODUCTIONThe coast zone is the area where most human activities take place and where the highest economic benefit is produced. The knowledge of the distribution and variation of primary production provides the bases as reference helping the marine exploitation and management.
基金supported by the National Natural Science Foundation of China (No.41576164)the ‘Strategic Priority Research Program-Western Pacific Ocean System:Structure,Dynamics and Consequences’ of the Chinese Academy of Sciences (No.XDA11020103.1)NSFC-Shandong Joint Fund for Marine Ecology and Environmental Sciences (No.U1606404)
文摘There were different biogeographical tintinnids in the oceans. Knowledge of their distribution pattern and mixing was important to the understanding of ecosystem functions. Yellow Sea(YS) and Bohai Sea(BS) were semi-enclosed seas influenced by warm water intrusion and YS cold bottom water. The occurrence of tintinnids in YS and BS during two cruises(summer and winter) were investigated to find out: i) whether warm-water tintinnids appeared in YS and BS; ii) whether boreal tintinnids appeared in high summer; iii) the core area of neritic tintinnids and iv) how these different biogeographical tintinnids mixed. Our results showed that tintinnid community was dominated by neritic tintinnid. We confirmed the occurrence of warm-water tintinnids in summer and winter. In summer, they intruded into BS and mainly distributed in the upper 20 m where Yellow Sea Surface Warm Water(YSSWW) developed. In winter, they were limited in the surface water of central deep region(bottom depth >50 m) of YS where were affected by Yellow Sea Warm Water(YSWW). Boreal tintinnids occurred in YS in high summer(August) and in winter, while they were not observed in BS. In summer, the highest abundance of boreal tintinnids occurred in Yellow Sea Bottom Cold Water, indicating the presence of an oversummering stock. In winter, they were concentrated in the north of YSWW. Vertically, neritic tintinnids abundance was high in the bottom layers. Horizontally, high neritic tintinnids abundance in bottom layers occurred along the 50 m isobath coinciding with the position of front systems. Front systems were the core distribution area of neritic tintinnids. High abundance areas of warm-water and boreal tintinnids were clearly separated vertically in summer, and horizontally in winter. High abundance of neritic tintinnids rarely overlapped with that of warm-water or boreal tintinnids.
文摘Grain size analysis, X ray diffraction analysis and biostratigraphy analysis of the structure, composition and formation conditions of the neritic silty clay facies sediments extensively distributed in the central part of the South Yellow Sea showed that the sediments were composed of more than 70% clay, less than 30% silt, had very little or no sand, and were characterized by homogenous texture, soapy feeling, high plasticity, light green gray color and elliptical distribution being about 3 m thick in the center, being thinner towards the margin and finally thinning out. These shelf cyclonic eddy environment sediments formed a sedimentary facies different from that of the sediments in the neighbouring area and revealed the particular sediment dynamic pattern in the environment.
文摘Mixed deposition is a sedimentary phenomenon of special significance to the tectonic movement, material supply, sea level change, andpaleoclimate of the sedimentary environment. The sediments of the Late Carboniferous-Early Permian System in the North China Craton, whichare composed of clastic rock and limestone, are mixed clastic-platform carbonate sediments in the epicontinental sea. Based on the geologicaland well logging data of nearly 100 exploratory wells and hundreds of development wells in the region, the lithologic association and cyclefeatures of the Upper Carboniferous-Lower Permian were determined. From this data, the Benxi Formation and the Taiyuan Formation of theDaniudi Gasfield are considered to belong to a mixed clastic coastline-carbonate platform sedimentary system and coastal plain sedimentarysystem in the epicontinental sea. Based on the six transgressions and regressions during the Late Carboniferous-Early Permian epochs in theregion, combined with the regional evolution history, this study analyzed the sedimentary evolution history of the Daniudi Gasfield from the LateCarboniferous to the Early Permian.
基金This work was supported by the Science and Technology Planning Project of Guangzhou(No.202002030489)Guangdong MEPP Fund[No.GDOE(2019)A23]+1 种基金Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(GML2019ZD0405)Natural Science Foundation of China(No.32070517,41576124,31772440,31761133001).
文摘As an important component of microzooplankton,ciliates play a key role in matter cycling and energy fow in marine planktonic ecosystems.Studies of planktonic ciliate have been extensive in the South China Sea(SCS)over the last 20 years.Here,we summarize the recent progress on the diversity and distribution of this group in the SCS.This includes that in:(1)the waters covering the intertidal zone of the northern SCS,most studies have focused on taxonomy,with 71 species collected,identifed,and described(with~40%new species);(2)neritic waters distribution patterns have been examined at a regional scale,with ciliates displaying signifcant spatial variations and seasonal dynamics;(3)in oceanic waters,there has been a focus on ciliate distribution in north,centre,and south regions,where mesoscale physical processes play roles in controlling distributions,and noticeable vertical variations occur.More generally,some studies examine the infuences of environment variables on ciliates,and indicate that chlorophyll a concentration is commonly positively correlated with ciliates abundance.In addition,some signifcant fndings are summarized,the limitations of past studies are considered,and recommendations are made for future work on planktonic ciliates in SCS.
