四川软玉猫眼赋存的围岩显微结构研究

对四川软玉猫眼的赋存围岩一蛇纹石化辉橄岩和橄榄岩的岩石显微结构的研究结果表明：围岩的主要结构类型为网格状结构和交代假象结构。交代假象结构又可分为橄榄石假象和辉石假象两种。辉石假象有两种表现形式：其一为蛇纹石交代辉石而保留辉石的晶形；另一种表现为由辉石蚀变所析出的磁铁矿经浓集而形成肋状条纹以及磁铁矿向辉石边缘迁移而形成浓缩边。研究认为：在超基性岩体蚀变过程中，首先发生橄榄石化和辉石化，生成蛇纹石。而后蛇纹石对与其接触的碳酸盐岩发生接触交代，吸收围岩中的钙而形成软玉。

Study on the microstructures of surrounding rock hosting nephrite cat's eye from Sichuan province

The Microstructures of surrounding rock-clinopyroxene and metamorphic peridotite hosting Nephrie Cat's Eye newly discovered in Sichuan Province, Southwest of China were studied in this paper. The results show that the main microstructures of surrounding rocks include the netted texture and metasomatic pseudomor-phic texture. The latter can be divided into two branches:olivine and pytoxene metasomatic pseudomorphic texture. Pyroxene in metasimatic pseudomorphic texture was replaced by serpentime as well as by magnetite , which was condensed at the side of pytoxene. It is reached cinclusion that during metamorphism, serpentime was firstly replaced by olivine and pyroxene. Then,serpentine replaced carbonate touching it,absorbing the element calcium from carbonate and forming nephrite.