中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
Slowing Extrusion Tectonics and Accelerated Uplift of Northern Tibet Since the Mid-Miocene

文献类型:期刊论文

作者Lu, Haijian1,5,6; Cao, Xinwen2; Malusa, Marco G.3; Zhang, Zhiyong4; Pan, Jiawei1,5,6; Li, Haibing1,5,6
刊名TECTONICS
出版日期2023-08-01
卷号42期号:8页码:23
ISSN号0278-7407
关键词anisotropy of magnetic susceptibility paleostress field rotation slip partitioning tectonic extrusion northern Tibet
DOI10.1029/2023TC007801
英文摘要Mechanisms of northern Tibet crustal thickening are strongly debated. Here we present a high-resolution and continuous record (24-4.8 Ma) of anisotropy of magnetic susceptibility and paleomagnetic declination from the Dahonggou section in the northern Qaidam Basin, northern Tibet. Our results reveal two major clockwise rotations of the regional paleostress field at similar to 15 Ma (similar to 20 degrees) and similar to 8.4 Ma (similar to 15 degrees), coeval with episodes of mountain building and basin deformation in northern Tibet. We suggest that simultaneous stress field rotation and uplift observed in the study area are related to progressively slowing lateral-extrusion tectonics along boundary-parallel strike-slip faults (Altyn Tagh and Haiyuan faults). The 15 Ma event can be explained by the transition from northeastward to eastward extrusion of northern Tibet materials due to the obstruction of the rigid Alxa block. As deformation keeps migrating toward the east, the 8 Ma event is possibly related to a change from eastward to southeastward extrusion of northeastern Tibet materials as a result of the resistance of the rigid Ordos block. We conclude that Tibetan deformation evolved through successive stages of slowing extrusion tectonics since the mid-Miocene. Deformation was initially localized along pre-existing lithospheric structures, and subsequently more distributed under confining boundary conditions, leading to crustal thickening and uniform uplift of northern Tibet during the late stage of plateau development. Plain Language Summary How northern Tibet evolved as a far-field response to the India-Asian collision remains an open question. Here we present high-resolution and continuous record (24-4.8 Ma) of anisotropy of magnetic susceptibility and paleomagnetic declination from a well-exposed sedimentary section in the northern Qaidam Basin, northern Tibet. The results indicate two significant clockwise rotations (similar to 20 degrees and similar to 15 degrees) of the regional paleostress field at 15 and 8.4 Ma. Interestingly, these two ages are characterized by large-scale mountain building, basin deformation and initiation or slowdown of major strike-slip faulting in northern Tibet. Given that the relatively weak northern Tibet crust is surrounded by several rigid blocks on its northern and eastern sides, we suggest that Tibetan deformation patterns since the mid-Miocene was associated with successive stages of a weakening extrusion process (from NE- to E-directed extrusion at 15 Ma and from E- to SE-directed extrusion at similar to 8 Ma) that exploits pre-existing lithospheric weak zones. This study lend support to the dominant role of strain transfer from localized strike-slip faulting to distributed thickening deformation under confining boundary conditions in raising the crust of northern Tibet uniformly during the late stage of plateau development.
WOS关键词ALTYN-TAGH FAULT ; RESOLUTION MAGNETO STRATIGRAPHY ; LATE CENOZOIC DEFORMATION ; INDIA-ASIA COLLISION ; CENTRAL QAIDAM BASIN ; QILIAN SHAN ; STRIKE-SLIP ; NORTHEASTERN MARGIN ; HAIYUAN FAULT ; NE TIBET
资助项目Second Tibetan Plateau Scientific Expedition and Research Program[2019QZKK0901] ; China Geological Survey[DD20221630]
WOS研究方向Geochemistry & Geophysics
语种英语
出版者AMER GEOPHYSICAL UNION
WOS记录号WOS:001037529900001
资助机构Second Tibetan Plateau Scientific Expedition and Research Program ; Second Tibetan Plateau Scientific Expedition and Research Program ; China Geological Survey ; China Geological Survey ; Second Tibetan Plateau Scientific Expedition and Research Program ; Second Tibetan Plateau Scientific Expedition and Research Program ; China Geological Survey ; China Geological Survey ; Second Tibetan Plateau Scientific Expedition and Research Program ; Second Tibetan Plateau Scientific Expedition and Research Program ; China Geological Survey ; China Geological Survey ; Second Tibetan Plateau Scientific Expedition and Research Program ; Second Tibetan Plateau Scientific Expedition and Research Program ; China Geological Survey ; China Geological Survey
源URL[http://ir.iggcas.ac.cn/handle/132A11/111331]  
专题地质与地球物理研究所_岩石圈演化国家重点实验室
通讯作者Lu, Haijian
作者单位1.Jiangsu Donghai Crustal Act Deep Holes Continental, Lianyungang, Peoples R China
2.Chinese Acad Geol Sci, Inst Geomech, Beijing, Peoples R China
3.Univ Milano Bicocca, Milan, Italy
4.Chinese Acad Sci, Inst Geol & Geophys, Beijing, Peoples R China
5.Chinese Acad Geol Sci, Inst Geol, Key Lab Deep Earth Dynam, Minist Nat Resources, Beijing, Peoples R China
6.Southern Marine Sci & Engn Guangdong Lab Guangzhou, Guangzhou, Peoples R China
推荐引用方式
GB/T 7714
Lu, Haijian,Cao, Xinwen,Malusa, Marco G.,et al. Slowing Extrusion Tectonics and Accelerated Uplift of Northern Tibet Since the Mid-Miocene[J]. TECTONICS,2023,42(8):23.
APA Lu, Haijian,Cao, Xinwen,Malusa, Marco G.,Zhang, Zhiyong,Pan, Jiawei,&Li, Haibing.(2023).Slowing Extrusion Tectonics and Accelerated Uplift of Northern Tibet Since the Mid-Miocene.TECTONICS,42(8),23.
MLA Lu, Haijian,et al."Slowing Extrusion Tectonics and Accelerated Uplift of Northern Tibet Since the Mid-Miocene".TECTONICS 42.8(2023):23.

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来源:地质与地球物理研究所

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