摘要
鞍本地区鞍山群变质岩出露区可分为鞍山、辽阳、本溪三个小区。所有的变质岩均属角闪岩相,从西向东,变质程度递增。三个小区最先出现的特征变质矿物分别是铁铝榴石、十字石和夕线石。退化变质作用由西向东递减,在东-西鞍山矿区已退变为绿片岩相,在绿泥片岩中普通角闪石仅作为残留矿物出现在绿泥石的核心。鞍山小岭子矿区有紫苏辉石、红柱石和尖晶石组合,它们是燕山期花岗岩围岩中的接触变质矿物。
Anshan Archaean metamorphic complex occurs in Anshan-Benxi area that can be subdivided into three districts, i.e., Anshan, Liaoyang and Benxi. The metamorphic grade of all the rocks belongs to amphiholite facies. In general, the grade of metamorphism increases from the west to the east. The typical metamorphic minerals which firstly occur in the metamorphic rocks are respectively almandine, staurolite and sillimanite in Anshan, Liaoyang and Benxi. Nevertheless, the grade of retrogressive metamorphism with strong deformation increases from the east to the west, and the metamorphic rocks in Anshan district have become greenschist facies ones. The previous metamorphic minerals of amphibolite facies occur only as metasomatic residual minerals in chlorite and sericite. Hypersthene, andalusite and spinel have been found in metamorphic rocks at Xiaolingzi in Anshan district. The metamorphic grade of these rocks discords with other rocks in the same district. It is evident that these rocks suffered contact metamorphism after regional metamorphism of amphibolite facies.
出处
《岩石矿物学杂志》
CAS
CSCD
1990年第2期148-158,共11页
Acta Petrologica et Mineralogica
关键词
鞍山群
矿物
变质
Anshan group
metamorphic minerals
P-T condition
