藏南冈底斯岩浆带研究进展与展望
Research Progress and Prospect of the Gangdese Magmatic Belt in Southern Tibet
Online published: 2022-02-20
孟元库, 袁昊岐, 魏友卿, 张书凯, 刘金庆 . 藏南冈底斯岩浆带研究进展与展望[J]. 高校地质学报, 2022 , 28(1) : 1 -31 . DOI: 10.16108/j.issn1006-7493.2020057
scientific problems from thirteen aspects. It is shown that the Gangdese magmatic belt is a typical magmatism-tectonismmineralization-deformational metamorphism belt and experienced multi-stage evolution processes rather than a simple
continental magmatic arc aggregated in the Lhasa terrane. The review shows that (1) the Gangdese magmatic belt is a natural
laboratory for studying the evolution history of the Neo-Tethys, and provides better constraints on the styles of the subducting
slab. (2) The different-stage granitoid stocks and batholiths might be formed by multiple additions and incremental assembly of
magmas over a span of millions of years or even longer. Therefore, we should use a mush model to reconstruct petrogenesis and
petrogenetic secnarios of granitoid rocks in detail. (3) The mantle nature of the Gangdese region shows complicated features that
are characterized by geochemical heterogeneity along the arc strike direction. (4) The reversed isotopes exist in the Gangdese belt, probably indicating an ancient nucleus. (5) The Gangdese belt is tilting and has different crustal compositions that are characterized by lower crustal compositions in the eastern segment and middle-upper crustal compositions in the middle-western segment. Crustal tilting of the Gangdese region suggests a differential and imbalanced exhumation process. (6) At present, numerous studies are focused on igneous rocks with methods mainly including radioactive Sr-Nd-Hf isotopes, whereas non-traditional stable isotopes (Mg-O-Li-B-Mo) are rarely reported. In addition, research topics are mainly associated with petrogenesis and geochronology, but few studies focus on the magma emplacement and post-magmatic deformation and uplifting-denudation processes. (7) Research in structural geology of the area is few and usually tectonic evolution is inferred from magmatic evolution in the Gangdese belt, southern Tibet. Finally, we also provide future prospects based on the current research status of the Gangdese magmatic belt in southern Tibet.
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