A thrust-fold belt consisting of a series of thrusts and buckling folds developed in the Mesozoic and Cenozoic strata within the Kuqa Depression,Tarim Basin.In this study,a structural interpretation model of the Kuqa ...A thrust-fold belt consisting of a series of thrusts and buckling folds developed in the Mesozoic and Cenozoic strata within the Kuqa Depression,Tarim Basin.In this study,a structural interpretation model of the Kuqa Depression is established and the Mesozoic proto-basin is reconstructed on the basis of outcrop geology along the basin margin,seismic,well-log and CEMP data.The model is called‘delaminate contractional deformation',which emphasizes the decoupling between the Cenozoic,Mesozoic,pre-Mesozoic and the basin-basement within the Kuqa Depression,but there is no unified detachment.The model has a shortening amount ranging from 12 km to 16 km and the depth involved in contractional deformation ranges from 21 km to 28 km.A prototype of the Mesozoic basin reconstructed by interpretation model is a subbasin superposed on the transitional zone between the uplift at the northern edge of the Tarim Craton and the southern Tianshan orogenic wedge formed in the Hercynian orogeny.Lithospheric thermal and crustal isostatic activity after the Hercynian orogeny maybe the controlling dynamic factors of basin subsidence during the Mesozoic and early Cenozoic,the difference in rock mechanical properties between different levels,craton and orogenic wedge being the major cause of the‘delaminate contractional deformation'during the Himalayan orogeny.展开更多
Caledonian orogeny is another important tectonic event in South China Block after the breakup of the Rodinia supercontinent.With a view to constrain the tectonic evolution and proto-basin in South China,this paper rep...Caledonian orogeny is another important tectonic event in South China Block after the breakup of the Rodinia supercontinent.With a view to constrain the tectonic evolution and proto-basin in South China,this paper reports the geochemical and zircon U-Pb dating data of the Ordovician strata in central Hunan,South China.Geochemical features and paleocurrent directions suggest that the lower Ordovician deposited in a passive continental margin basin with a provenance of quartzose components and showing an affinity with the Yangtze Block.U-Pb age data for 260 detrital zircons from upper Ordovician identify three major age populations as:900-1200 Ma,1400-1800 Ma and 2400-2700 Ma.The detrital zircon age spectrum as well as the paleocurrent directions suggest that upper Ordovician deposited in a foreland basin and showing a close affinity with the Cathaysia Block.It is also suggest that the lower Ordovician continuously accepted the mineral from the Yangtze Block,whereas the provenance of the upper Ordovician sedimentary basin changed from the Yangtze Block to the Cathaysia Block.This change implies a tectonic movement,which caused the transformation of the proto-basin in the Hunan area in SCB from passive continental margin basin to foreland basin probably took place during late Ordovician.This fact also demonstrate that the Caledonian orogeny in South China Block began no later than 453 Ma,and a new crustal evolution model is proposed.展开更多
Temporal and spatial evolution of proto-basins and magmatism in the North China Craton might provide information of its destruction.Overall,the destruction of the North China Craton is a heterogeneous process of botto...Temporal and spatial evolution of proto-basins and magmatism in the North China Craton might provide information of its destruction.Overall,the destruction of the North China Craton is a heterogeneous process of bottom upward and from margin toward interior,related to multiple interactions between the craton and its surrounding plates.The interior of craton would be initially destructed during the Early-Middle Jurassic.Subduction of the Paleo-Asian Ocean Plate may have destructed the northern margin of the North China Craton.Collision of the Yangtze Plate with the North China Craton is significant for the magmatic and tectonic activities during the Late Triassic-Middle Jurassic.Subductions of the Izanagi and Paleo-Pacific plates lead to the ultimate destruction of the North China Craton.Temporal and spatial evolution of the proto-basins and related magmatism in the North China Craton indicate that the dominant mechanism of the cratonic destruction may be thermal mechanical-chemical erosion.展开更多
基金supported by the National Science and Technology Major Special Project(Grant No.2011ZX05003-004)the National Key Basic Research Development Plan(Grant No.2011CB201100)。
文摘A thrust-fold belt consisting of a series of thrusts and buckling folds developed in the Mesozoic and Cenozoic strata within the Kuqa Depression,Tarim Basin.In this study,a structural interpretation model of the Kuqa Depression is established and the Mesozoic proto-basin is reconstructed on the basis of outcrop geology along the basin margin,seismic,well-log and CEMP data.The model is called‘delaminate contractional deformation',which emphasizes the decoupling between the Cenozoic,Mesozoic,pre-Mesozoic and the basin-basement within the Kuqa Depression,but there is no unified detachment.The model has a shortening amount ranging from 12 km to 16 km and the depth involved in contractional deformation ranges from 21 km to 28 km.A prototype of the Mesozoic basin reconstructed by interpretation model is a subbasin superposed on the transitional zone between the uplift at the northern edge of the Tarim Craton and the southern Tianshan orogenic wedge formed in the Hercynian orogeny.Lithospheric thermal and crustal isostatic activity after the Hercynian orogeny maybe the controlling dynamic factors of basin subsidence during the Mesozoic and early Cenozoic,the difference in rock mechanical properties between different levels,craton and orogenic wedge being the major cause of the‘delaminate contractional deformation'during the Himalayan orogeny.
基金financially supported by the China Geological Survey(Nos.DD20190370,121201111120117 and 121201102000150012-32)。
文摘Caledonian orogeny is another important tectonic event in South China Block after the breakup of the Rodinia supercontinent.With a view to constrain the tectonic evolution and proto-basin in South China,this paper reports the geochemical and zircon U-Pb dating data of the Ordovician strata in central Hunan,South China.Geochemical features and paleocurrent directions suggest that the lower Ordovician deposited in a passive continental margin basin with a provenance of quartzose components and showing an affinity with the Yangtze Block.U-Pb age data for 260 detrital zircons from upper Ordovician identify three major age populations as:900-1200 Ma,1400-1800 Ma and 2400-2700 Ma.The detrital zircon age spectrum as well as the paleocurrent directions suggest that upper Ordovician deposited in a foreland basin and showing a close affinity with the Cathaysia Block.It is also suggest that the lower Ordovician continuously accepted the mineral from the Yangtze Block,whereas the provenance of the upper Ordovician sedimentary basin changed from the Yangtze Block to the Cathaysia Block.This change implies a tectonic movement,which caused the transformation of the proto-basin in the Hunan area in SCB from passive continental margin basin to foreland basin probably took place during late Ordovician.This fact also demonstrate that the Caledonian orogeny in South China Block began no later than 453 Ma,and a new crustal evolution model is proposed.
基金supported by National Natural Science Foundation of China(Grant Nos.41003017,41273042,70914001)Knowledge Innovation Project of Chinese Academy of Sciences(Grant No.KZCX1-YW-15-1)
文摘Temporal and spatial evolution of proto-basins and magmatism in the North China Craton might provide information of its destruction.Overall,the destruction of the North China Craton is a heterogeneous process of bottom upward and from margin toward interior,related to multiple interactions between the craton and its surrounding plates.The interior of craton would be initially destructed during the Early-Middle Jurassic.Subduction of the Paleo-Asian Ocean Plate may have destructed the northern margin of the North China Craton.Collision of the Yangtze Plate with the North China Craton is significant for the magmatic and tectonic activities during the Late Triassic-Middle Jurassic.Subductions of the Izanagi and Paleo-Pacific plates lead to the ultimate destruction of the North China Craton.Temporal and spatial evolution of the proto-basins and related magmatism in the North China Craton indicate that the dominant mechanism of the cratonic destruction may be thermal mechanical-chemical erosion.
