Adakites from continental collision zones: Melting of thickened lower crust beneath southern Tibet

Sun Lin Chung, Dunyi Liu, Jianqing Ji, Mei Fei Chu, Hao Yang Lee, Da Jen Wen, Ching Hua Lo, Tung Yi Lee, Qing Qian, Qi Zhang

研究成果: 雜誌貢獻文章

798 引文 斯高帕斯(Scopus)

摘要

Adakites are geochemically distinct intermediate to felsic lavas found exclusively in subduction zones. Here we report the first example of such magmas from southern Tibet in an active continental collision environment. The Tibetan adakites were emplaced from ca. 26 to 10 Ma, and their overall geochemical characteristics suggest an origin by melting of eclogites and/or garnet amphibolites in the lower part (≥50 km) of thickened Tibetan crust. This lower-crustal melting required a significantly elevated geotherm, which we attribute to removal of the tectonically thickened lithospheric mantle in late Oligocene time. The identification of collision-type adakites from southern Tibet lends new constraints to not only the Himalayan-Tibetan orogenesis-how and when the Indian lithosphere started underthrusting Asia can be depicted-but also the growth of the early continental crust on Earth that consists dominantly of the tonalite-trondhjemite-granodiorite suites marked by adakitic geochemical affinities.

原文英語
頁(從 - 到)1021-1024
頁數4
期刊Geology
31
發行號11
DOIs
出版狀態已發佈 - 2003 十一月 1

ASJC Scopus subject areas

  • Geology

指紋 深入研究「Adakites from continental collision zones: Melting of thickened lower crust beneath southern Tibet」主題。共同形成了獨特的指紋。

  • 引用此

    Chung, S. L., Liu, D., Ji, J., Chu, M. F., Lee, H. Y., Wen, D. J., Lo, C. H., Lee, T. Y., Qian, Q., & Zhang, Q. (2003). Adakites from continental collision zones: Melting of thickened lower crust beneath southern Tibet. Geology, 31(11), 1021-1024. https://doi.org/10.1130/G19796.1