As the link connecting the South China Continent and the northern South China Sea(SCS),the Pearl River is the focus of sedimentology and petroleum geology research.Its evolutionary process and controlling factors are ...As the link connecting the South China Continent and the northern South China Sea(SCS),the Pearl River is the focus of sedimentology and petroleum geology research.Its evolutionary process and controlling factors are of great significance in revealing the East Asian continental landscape reorganization during the Late Cenozoic.Based on published data,’source-to-sink’provenance analyses allow systematic deliberation on the birth and evolutionary history of the Pearl River.Close to the Oligocene/Miocene boundary,an abrupt shift in the sedimentary composition indicates significant westward and northward expansion of the river’s watershed area,followed by the establishment of a near-modern fluvial network.This sedimentary change generally concurred with a series of regional geological events,including the onset of the Yangtze throughflow,large-scale development of the loess plateau,and formation of the northwestern arid zone and Asian Monsoon system.These major changes in the geology-climate-ecoenvironment system are in close response to the process of the Cenozoic Xizang(Tibetan)Plateau uplift.Consequently,the East Asian continental landscape and most of midCenozoic drainage systems underwent critical reversion into east-tilting,or east-flowing networks.展开更多
Located at the end of the northern Manila Trench,the Hengchun Peninsula is the latest exposed part of Taiwan Island,and preserves a complete sequence of accretionary deep-sea turbidite sandstones.Combined with extensi...Located at the end of the northern Manila Trench,the Hengchun Peninsula is the latest exposed part of Taiwan Island,and preserves a complete sequence of accretionary deep-sea turbidite sandstones.Combined with extensive field observations,a’source-to-sink’approach was employed to systematically analyze the formation and evolutionary process of the accretionary prism turbidites on the Hengchun Peninsula.Lying at the base of the Hengchun turbidites are abundant mafic normal oceanic crust gravels with a certain degree of roundness.The gravels with U-Pb ages ranging from 25.4 to23.6 Ma are underlain by hundreds-of-meters thickness of younger deep-sea sandstone turbidites with interbedded gravels.This indicates that large amounts of terrigenous materials from both the’Kontum-Ying-Qiong’River of Indochina and the Pearl River of South China were transported into the deep-water areas of the northern South China Sea during the late Miocene and further eastward in the form of turbidity currents.The turbidity flow drastically eroded and snatched mafic materials from the normal South China Sea oceanic crust along the way,and subsequently unloaded large bodies of basic gravel-bearing sandstones to form turbidites near the northern Manila Trench.With the Philippine Sea Plate drifting clockwise to the northwest,these turbidite successions eventually migrated and,since the Middle Pleistocene,were exposed as an accretionary prism on the Hengchun Peninsula.展开更多
The process of Cenozoic sea-land changes in the northern South China Sea(SCS)controlled the sedimentary filling pattern and played an important role in the petroleum geological characteristics of the northern marginal...The process of Cenozoic sea-land changes in the northern South China Sea(SCS)controlled the sedimentary filling pattern and played an important role in the petroleum geological characteristics of the northern marginal sedimentary basins.Under the control of the opening process of the SCS,the northern SCS Cenozoic transgression generally showed the characteristics of early in the east and late in the west,and early in the south and late in the north.The initial transgression occurred in the Eocene in the Taixinan Basin(TXNB)of the eastern SCS,while the transgression occurred until the Pliocene in the Yinggehai Basin(YGHB)of the western SCS.International Ocean Discovery Program(IODP)expeditions(Expeditions 367/368)revealed that the initial transgression of the SCS basin occurred at approximately 34 Ma,which was the initial opening time of the SCS.The period of drastic changes in the sedimentary environment caused by large-scale transgression corresponded to the opening time of the southwestern subbasin(approximately 23 Ma),which also represented the peak of the spreading of the SCS.The sea-land transition process controls the distribution of alternating continent-marine facies,marine facies source rocks and reservoirs in the basins.The marine facies source rocks of the basins in the northern SCS have a trend of gradually becoming younger from east to west,which is consistent with the regional process of gradual transgression from east to west.Regional sea-level changes were comprehensively influenced by SCS opening and global sea-level changes.These processes led to the early development in the east and south and late development in the west and north for the carbonate platform in the SCS.Carbonate platforms form another type of"selfgenerating and self-accumulating"oil-gas reservoir in the northern SCS.The sea-land transition controlled the depositional filling patterns of different basins and laid the foundation of marine deposits for oil and gas resources.The source-reservoircap assemblage in the northern SCS was controlled horizontally by provenance supply and sedimentary environmental changes caused by sea-land transition and vertically by the tectonic evolution of the SCS and regional sea-level changes.展开更多
Geochemical and detrital zircon U-Pb dating data for drilled sediments from the Baiyun deepwater area of the northern South China Sea demonstrate a change of sedimentary sources from the Oligocene to the Miocene.Zirco...Geochemical and detrital zircon U-Pb dating data for drilled sediments from the Baiyun deepwater area of the northern South China Sea demonstrate a change of sedimentary sources from the Oligocene to the Miocene.Zircon ages of the pre-rift Eocene sequences are dominated by Yanshanian ages with various peak values（110–115 Ma for U1435 and L21; 150 Ma for H1）, indicating local sediment supply from the pre-existing Mesozoic magmatic belt. For the Oligocene sediments in the northern part of the basin, the rare earth elements show different distribution characteristics, indicating sediment supply from the paleo-Zhujiang River（Pearl River）, as also confirmed by the multimodal zircon age spectra of the Lower Oligocene strata in Well X28. By contrast, a positive Eu anomaly characterizes sediments from the western and southern parts of the basin, indicating potential provenances from intermediate to basic volcanic rock materials. The Baiyun Movement at the end of the Oligocene contributed to a large-scale subsidence in the deepwater area and also a northward retreat of continental shelf break, leading to deepening depositional environment in the basin. As a result, all the detrital zircon ages of the Upper Oligocene strata from Wells X28, L13, and L21 share a similar distribution, implying the possible control of a common source like the Zhujiang River. During the Miocene, whereas sediments in the northern area were mainly sourced from the Zhujiang River Delta, and those in the southern deepwater area continued to be affected by basic volcanic activities, the Dongsha Uplift could have contributed as the main source to the eastern area.展开更多
基金supported by the National Natural Science Foundation of China(grant Nos.42076066,92055203 and 41874076)the National Science and Technology Major Project of China(grant No.2016ZX05026004-002)the National Key Research and Development Program of China(grant No.2018YFE0202400)。
文摘As the link connecting the South China Continent and the northern South China Sea(SCS),the Pearl River is the focus of sedimentology and petroleum geology research.Its evolutionary process and controlling factors are of great significance in revealing the East Asian continental landscape reorganization during the Late Cenozoic.Based on published data,’source-to-sink’provenance analyses allow systematic deliberation on the birth and evolutionary history of the Pearl River.Close to the Oligocene/Miocene boundary,an abrupt shift in the sedimentary composition indicates significant westward and northward expansion of the river’s watershed area,followed by the establishment of a near-modern fluvial network.This sedimentary change generally concurred with a series of regional geological events,including the onset of the Yangtze throughflow,large-scale development of the loess plateau,and formation of the northwestern arid zone and Asian Monsoon system.These major changes in the geology-climate-ecoenvironment system are in close response to the process of the Cenozoic Xizang(Tibetan)Plateau uplift.Consequently,the East Asian continental landscape and most of midCenozoic drainage systems underwent critical reversion into east-tilting,or east-flowing networks.
基金supported by the National Natural Science Foundation of China(grant nos 42076066,92055203 and 41874076)the National Science and Technology Major Project of China(grant no.2016ZX05026004-002)the National Key Research and Development Program of China(grant no.2018YFE0202400)。
文摘Located at the end of the northern Manila Trench,the Hengchun Peninsula is the latest exposed part of Taiwan Island,and preserves a complete sequence of accretionary deep-sea turbidite sandstones.Combined with extensive field observations,a’source-to-sink’approach was employed to systematically analyze the formation and evolutionary process of the accretionary prism turbidites on the Hengchun Peninsula.Lying at the base of the Hengchun turbidites are abundant mafic normal oceanic crust gravels with a certain degree of roundness.The gravels with U-Pb ages ranging from 25.4 to23.6 Ma are underlain by hundreds-of-meters thickness of younger deep-sea sandstone turbidites with interbedded gravels.This indicates that large amounts of terrigenous materials from both the’Kontum-Ying-Qiong’River of Indochina and the Pearl River of South China were transported into the deep-water areas of the northern South China Sea during the late Miocene and further eastward in the form of turbidity currents.The turbidity flow drastically eroded and snatched mafic materials from the normal South China Sea oceanic crust along the way,and subsequently unloaded large bodies of basic gravel-bearing sandstones to form turbidites near the northern Manila Trench.With the Philippine Sea Plate drifting clockwise to the northwest,these turbidite successions eventually migrated and,since the Middle Pleistocene,were exposed as an accretionary prism on the Hengchun Peninsula.
基金granted by the National Natural Science Foundation of China(Grant No.42076066,92055203 and 41874076)the National Science and Technology Major Project(Grant No.2016ZX05026–004)the National Key Research and Development Program of China(Grant No.2018YFE0202400)。
文摘The process of Cenozoic sea-land changes in the northern South China Sea(SCS)controlled the sedimentary filling pattern and played an important role in the petroleum geological characteristics of the northern marginal sedimentary basins.Under the control of the opening process of the SCS,the northern SCS Cenozoic transgression generally showed the characteristics of early in the east and late in the west,and early in the south and late in the north.The initial transgression occurred in the Eocene in the Taixinan Basin(TXNB)of the eastern SCS,while the transgression occurred until the Pliocene in the Yinggehai Basin(YGHB)of the western SCS.International Ocean Discovery Program(IODP)expeditions(Expeditions 367/368)revealed that the initial transgression of the SCS basin occurred at approximately 34 Ma,which was the initial opening time of the SCS.The period of drastic changes in the sedimentary environment caused by large-scale transgression corresponded to the opening time of the southwestern subbasin(approximately 23 Ma),which also represented the peak of the spreading of the SCS.The sea-land transition process controls the distribution of alternating continent-marine facies,marine facies source rocks and reservoirs in the basins.The marine facies source rocks of the basins in the northern SCS have a trend of gradually becoming younger from east to west,which is consistent with the regional process of gradual transgression from east to west.Regional sea-level changes were comprehensively influenced by SCS opening and global sea-level changes.These processes led to the early development in the east and south and late development in the west and north for the carbonate platform in the SCS.Carbonate platforms form another type of"selfgenerating and self-accumulating"oil-gas reservoir in the northern SCS.The sea-land transition controlled the depositional filling patterns of different basins and laid the foundation of marine deposits for oil and gas resources.The source-reservoircap assemblage in the northern SCS was controlled horizontally by provenance supply and sedimentary environmental changes caused by sea-land transition and vertically by the tectonic evolution of the SCS and regional sea-level changes.
基金The National Natural Science Foundation of China under contract Nos 41576059,91128207 and 91528302the National Major Science and Technology Projects under contract No.2011ZX05025-006-02
文摘Geochemical and detrital zircon U-Pb dating data for drilled sediments from the Baiyun deepwater area of the northern South China Sea demonstrate a change of sedimentary sources from the Oligocene to the Miocene.Zircon ages of the pre-rift Eocene sequences are dominated by Yanshanian ages with various peak values（110–115 Ma for U1435 and L21; 150 Ma for H1）, indicating local sediment supply from the pre-existing Mesozoic magmatic belt. For the Oligocene sediments in the northern part of the basin, the rare earth elements show different distribution characteristics, indicating sediment supply from the paleo-Zhujiang River（Pearl River）, as also confirmed by the multimodal zircon age spectra of the Lower Oligocene strata in Well X28. By contrast, a positive Eu anomaly characterizes sediments from the western and southern parts of the basin, indicating potential provenances from intermediate to basic volcanic rock materials. The Baiyun Movement at the end of the Oligocene contributed to a large-scale subsidence in the deepwater area and also a northward retreat of continental shelf break, leading to deepening depositional environment in the basin. As a result, all the detrital zircon ages of the Upper Oligocene strata from Wells X28, L13, and L21 share a similar distribution, implying the possible control of a common source like the Zhujiang River. During the Miocene, whereas sediments in the northern area were mainly sourced from the Zhujiang River Delta, and those in the southern deepwater area continued to be affected by basic volcanic activities, the Dongsha Uplift could have contributed as the main source to the eastern area.
