Abstract
Two large east-trending granitic batholiths are exposed on the plateau of Central Tibet. In the southern Lhasa Terrane , north of the Zangbo Suture, the Gangdise Belt is a calc-alkaline composite batholith dominated by monzodiorites, tonalites, granodiorites and monzo granites. Trace elements indicate that strongly fractionated melts were emplaced at an active continental margin; deeper crustal levels of the batholith are exposed in the crustally -derived Nyainqentanglha orthogneiss. A long the northern edge o f the plateau , a syn-tectonic calcic to calc-alkaline suite of tonalites, granodiorites and monzo granites forms the Kunlun batholith with post-tectonic granites emplaced to the south. The Kunlun intrusions are derived from anatexis of a garnet-bearing source at in termediate crustal depths above an active or recently active continental margin . Between these two batholiths, a bimodal suite of metaluminous tonalite -grano-diorite and peraluminous two-mica granite is exposed in the northern Lhasa Terrane, indicative of melting both in the upper crust and at deeper levels in the crust or upper mantle. This association suggests a post-collision setting.
Reference23 articles.
1. Brown G. C. 1982 Calc-alkaline intrusive rocks: their diversity evolution and relation to volcanic arcs. In Andesites(ed. R. S. Thorpe) pp. 437-461. New York and London: Jo h n Wiley and Sons.
2. The geochemical characteristics of granitoids in contrasting arcs and comments on m agm a sources. J . geol;Brown G. C.;Soc.,1984
3. geotraverse of Tibet;Chang Chengfa;Nature Lond.,1985
4. The Four Plutonic Belts of the Transhimalaya-Himalaya: a Chemical, Mineralogical, Isotopic, and Chronological Synthesis along a Tibet-Nepal Section
5. Granites of western Karakorum and northern Kohistan (Pakistan): A composite mid-cretaceous to upper cenozoic magmatism
Cited by
128 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献