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岩相学证据表明大别山区超高压榴辉岩是绿帘角闪岩相岩石经超高压变质而成;碰撞造山峰期超高压变质之后,由于造山带的演化,地体隆升,超高压榴辉岩普遍表现近等温减压退变质,经高压榴辉岩相至角闪岩相,然后降温降压为绿帘角闪岩相及绿片岩相,有些超高压岩石则通过等压冷却过程达绿帘蓝片岩相而后降压降温为绿片岩相,随着退变质作用的进行,岩石经历多期变形可识别出6个世代,从塑性到脆性。减压P-T轨迹亦见于流体包裹体的演化,捕获压力可从2.05GPa近等温减压至<1.0GPa,含盐度显著降低,流体的Br/Cl和I/Cl比高于海水和全球平均值,说明流体来源是深部变质水。
The petrographic evidence shows that the ultrahigh-pressure eclogite in the Dabie area is formed by epithermal metamorphism of the epidote amphibolite facies. After the collision during the UHP metamorphism, due to the evolution of the orogenic belt, the uplift of the ground, Hyphaenites generally exhibit near-isothermal depressions and degenerations, passing through the high-pressure eclogite facies to amphibolite facies, and then depressurizing to greengrown amphibolite facies and greenschist facies, while some ultrahigh-pressure rocks pass the isobaric cooling process Green curtain blue lithofacies and then step-down cooling greenschist facies, with the degeneration and metamorphism, the rock experienced multi-stage deformation can be identified six generations, from plastic to brittle. Decompression PT trajectory is also seen in the evolution of fluid inclusions, the capture pressure can be nearly isothermal decompression from 2.05GPa to <1.0GPa, salinity decreased significantly, the fluid Br / Cl and I / Cl ratio higher than the sea water and the global average , Indicating that the fluid source is deep metamorphic water.