| 西藏南部新生代东西向伸展作用的深部岩浆作用响应 |
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| 关键词:silicocarbonatite lamproite sequential melting fluid-fluxed melting extension Southern Tibet |
| 基金项目:国家重点研发计划项目(编号: 2021YFC2901901)；国家自然科学基金项目(编号: 42372070; 92055202)；第二次青藏高原综合科学考察研究项目(编号: 2019QZKK0702)；中国地质科学院地质研究所基本科研业务费项目(编号: J2310)；中国地质调查局地质调查项目(编号: DD20221817; DD20221630) |
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| Deep Magmatism Response to Cenozoic E–W Extension in the Southern Tibet |
| With the rise of the Himalayan chain during the Cenozoic, southern Tibet experienced significant east–west extension, forming a series of north–south trending rifts. Along with the convective thinning or delamination of the thickened lithosphere, due to asthenospheric upwelling, sequential partial melting of the lithospheric mantle and middle-lower crust induced the formation of magmatic rocks with different petrological and geochemical characteristics. First, the partial melting of the enriched lithospheric mantle resulted in the formation of carbonatites, lamproites, and ultrapotassic rocks. Then, partial melting of the thickened basal lower-crust-derived granites with high Sr/Y ratio. Finally, the middle- and lower-crust metamorphic sedimentary rocks underwent fluid-fluxed or fluid-absent melting of muscovite, forming leucogranites. These new discoveries suggest that the initiation of the north–south trending rifts could have occurred as early as ~30 Ma and provide a typical example for interpreting the precise melting patterns of the continental lithosphere in orogenic belts and intracontinental extensional processes worldwide. |
| ZENG Lingsen,GAO Li’e,HU Guyue,XU Qian,TIAN Yihong,DONG Hanwen,WANG Yaying,YAN Lilong,ZHAO Linghao,LI Guangxu,DI Yinglong,HAO Guangming,WANG Haitao.2024.Deep Magmatism Response to Cenozoic E–W Extension in the Southern Tibet[J].Acta Geoscientica Sinica,45(6):871-881. |
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