Experimental study on dehydration melting of natural biotite-plagioclase gneiss from High Himalayas and implications for Himalayan crust anatexis |
| |
Authors: | Xiaosong Yang Zhenmin Jin Huenges Ernst Frank R. Schilling Wunder Bernd |
| |
Affiliation: | (1) Faculty of Earth Sciences, China University of Geosciences, 430074 Wuhan, China;(2) GeoForschungsZentrum, Potsdam, D-14473, Germany |
| |
Abstract: | Here we present the results of dehydration melting, melt morphology and fluid migration based on the dehydration melting experiments on natural biotite-plagioclase gneiss performed at the pressure of 1.0–1.4 GPa, and at the temperature of 770–1028°C. Experimental results demonstrate that: (i) most of melt tends to be distributed along mineral boundaries forming “melt filmrd even the amount of melt is less than 5 vol%; melt connectivity is controlled not only by melt topology but also by melt fraction; (ii) dehydration melting involves a series of subprocesses including subsolidus dehydration reaction, fluid migration, vapor-present melting and vapor-absent melting; (iii) experiments produce peraluminous granitic melt whose composition is similar to that of High Himalayan leucogranites (HHLG) and the residual phase assemblage is Pl+Qz+ Gat+Bio+Opx±Cpx+Ilm/Rut±Kfs and can be comparable with granulites observed in Himalayas. The experiments provide the evidence that biotite-plagioclase gneiss is one of source rocks of HHLG and dehydration melting is an important way to form HHLG and the granulites. Additionally, experimental results provide constraints on determining the P-T conditions of Himalayan crustal anatexis. |
| |
Keywords: | gneiss dehydration melting melt topology fluid migration leucogranite granulite Himalayas |
本文献已被 SpringerLink 等数据库收录! |
| 点击此处可从《科学通报(英文版)》浏览原始摘要信息 |
|
点击此处可从《科学通报(英文版)》下载全文 |