河南栾川软玉(白玉)矿床特征及成因的初步研究

Preliminary Study on the Characteristics and Genesis of Nephrite(White Jade)Deposit in Luanchuan,Henan Province

栾川软玉分布在东秦岭造山带北部,产于新元古代栾川群中部煤窑沟组上段,与蛇纹岩共生。玉矿体共有8个,呈透镜体或小脉状产出,玉石矿物成分主要为细粒透闪石,化学成分与和田白玉、国外软玉近似。蚀变主要有蛇纹石化、透闪石化等,属于多期、多方式的中低温复合变质蛇纹岩型软玉矿床。

Luanchuan nephrite is distributed in the north of the East Qinling orogenic belt and occurs in the upper part of the Mei-yaogou formation in the middle of the Neoproterozoic Luanchuan Group,which is associated with serpentinite.There are 8 jade ore bodies in total,which are lenticular or veinlike.The mineral com-position of jade is mainly fine-grained tremolite,and its chemical composition is similar to Hetian white jade and foreign nephrite.The alteration of Luanchuan deposit is mainly serpentinite and tremolite,which belongs to the multi-stage and multi-mode medi-um low temperature composite serpentinite type nephrite deposit.