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A set of nearly NS-trending rifts developed in the Himalayan orogen and southern Tibet, which are the large-scale extensional structures formed under the continuous compression of the Indo-Eurasia continent, playing a significant role in revealing the post-collisional evolution of the Tibetan Plateau. Different predictions have been made on the spatiotemporal distribution of these rifts through the existing hypothesis models, constituting the key factors constraining the formation system of the rifts. In this study we synthesized previous studies on the initiation time of rifting, and further clarified the spatiotemporal trend. The analysis results showed that the rifting initiated progressively earlier westward, which is consistent with the evolution of post-collisional magmatism in the Lhasa Terrain. Moreover, combined with the geophysical observations, it is inferred that the geodynamic mechanism of the nearly NS-trending rifts accords closely with the hypothesis model concerning the eastward-propagating lateral detachment of the subducted Indian slab. The Indian slab detachment resulted in asynchronous gravitational potential energy gradients, which drove the lithosphere flow eastward and eventually caused the eastward development of the rifting.

Geophysical features and crustal structure of the East China Sea basement were revealed based on geophysical inversion analysis with recent gravity and magnetic data. Our results show great differences between the East China Sea continental shelf basins and the Zhemin Volcanic Belt in the coastal South China Block with respect to geophysical features and crustal structures. These areas are separated by distinct geophysical and crustal changes, approximately along a line 100 km from the coastline of China. We hypothesize that the East China Sea basement is a buoyant allochthon in the Palaeo‐Pacific Plate, and that the East China margin was an Andean‐type active continental margin until the collision of the East China Sea basement with the South China Block in the Late Cretaceous, which jammed the Late Cretaceous Trench, terminating the subduction and the related granitoid magmatism. The East China continental margin was dominated by dextral transtension with limited magmatism due to the NNW‐trend motion of the Palaeo‐Pacific Plate with a reduced convergence rate until the Middle Eocene. The renewed westward subduction of the present‐day Pacific Plate replaced the East China Andean‐type continental margin with a Western Pacific‐type one. The detailed reconstructed tectonic model for the East China Sea since the Mesozoic is presented in this paper. [ABSTRACT FROM AUTHOR]

The Western Kunlun ranges and its foreland basin, the Tarim Basin, define the northwestmargin of the Tibetan Plateau, and provide important information on the Cenozoic expansionof the plateau after the India-Asia collision. In this study, we present a high-resolutionseismic reflection profile along the Hotan-Mazatagh transect of the Western Kunlun thrustsbelt in order to decipher the distribution of deformation and its propagation. Deformation inthis transect can be separated into three roughly east-west striking structures fromthe south to the north: the Hotan anticline, the Manan anticline, and the Mazataghthrust belt. The Hotan anticline is a fault-bend fold, mainly formed by the hangingwall sliding from the lower decóllement along the lower Cambrian units over apre-existing fault ramp into the upper decóllement that is located at the base ofthe Cenozoic strata. The Manan anticline, located ∼100 km north to the Hotananticline, is a reactivated low-amplitude fold with decreasing deformation upwards, theformation of which is mainly controlled by the lower decóllement. The Mazatagh thrustbelt, located ∼230 km north to the Hotan anticline, is controlled by both the upperdecóllement and the lower decóllement with the former ramping to the surface and thelatter building the Mazatagh anticline. The balanced cross-section reveals a totaldeformation of ∼28.93 km along this transect, with most deformation (∼25.0 km)transmitted by the upper decóllement among which at least 7.7 km of shortening hasbeen accommodated by the layer parallel compaction. The rest of shortening hasbeen absorbed by the Manan anticline (0.17 km) and the Mazatagh anticline (∼3.7km), respectively, transmitted along the lower decóllement. Our study highlightsthe effects of decóllement layer on transmitting deformation from the orogen intothe intracontinental region, the pre-existing structures on localizing distribution,and the penetrative strain on accommodating relatively homogeneous shortening. [ABSTRACT FROM AUTHOR]