摘要
大别山东段北部和南部榴辉岩的矿物组成和形成的温压条件有明显差异。北部榴辉岩有两种产状:一种产于超基性岩体内,另一种产于片麻岩內;它们均为石榴石-透辉石组合,不含石英,形成温度为600—740℃。南部榴辉岩均产于大别群片麻岩或大理岩中,为石榴石-绿辉石组合,含石英,形成温度为650—800℃。这些差异反映了它们形成环境不同,前者可能是俯冲洋壳在较深部位变质而成,后者可能与俯冲陆壳有关。
There are obvious differences in the mineral assemblage and metamorphic P-T conditions between the eclogitic rocks from the Northern and Southern Dabie Mountains. Those from the Northern Dabie Mountains are developed in Alpine peridotite and gneiss. Their mineral assemblage consists of garnet+diopside with no quartz, formed at temperatures of 600°—740℃. Those from the Southern Dabie Mountains are developed in gneiss and marble. Their mineral assemblage consists of garnet+omphosite+less quartz, metamorphosed in the range of 650°—800℃ These differences suggest that the former may be formed during the metamorphism of the subducted oceanic crust, whereas the latter may be genetically related to the subduction of the continental crust in this area.
出处
《地质学报》
EI
CAS
CSCD
北大核心
1993年第2期109-122,共14页
Acta Geologica Sinica
基金
国家自然科学基金(项目代号 4870188)
关键词
榴辉岩
成分
成因
造山带
collisional orogen, eclogitic rocks of the Southern and Northern Dabie Mountains, T-P conditions
