摘要
本文通过对中条山铜矿田电气石和电气石岩地质产状、岩相学和矿物学、矿物化学等特征的研究，指出本区有三种成因类型的电气石：（１）北峪酸性侵入体岩浆期后热液成因电气石；（２）中条群地层中变质热液形成的电气石；（３）赋矿岩石和近矿围岩中热液蚀变电气石。第（３）类电气石具有特征的产状、矿物化学和矿物共生组合标型。
This paper studies characteristics of geological modes of occurrence, petrography and mineralogy of tourmaline bearing rocks as well as mineral chemistry of tourmaline, and deals with the genesis of tourmaline. Four modes of occurrence of tourmaline are recognized: (1) tourmaline accompanied with Beiyu granodiorite and granite porphyry, (2) veinlike tourmaline bearing rocks in metamorphic strata, (3) striped tournaline bearing rocks, and (4) tourmaline veins in the host rocks. The main mineral chemical characteristics of tourmaline are as follows: (1) the contents of FeO and MgO vary considerably, and there are four types of mineral species: Fe tourmaline, Fe rich tourmaline, Mg Fe tourmaline and dravite;(2) the relative variations of Al 2O 3, FeO, MgO contents are closely associated with types of host rocks and geneses of tourmaline;(3) Na 2O, Al 2O 3 and FeO, TiO 2 contents of tourmaline assume growth and decline relationship in granite porphyry and granodiorite, which corresponds with the mutual compensational relation of chemical composition of the host rocks. There exist three genetic types of tourmaline: (1) tourmaline formed by post magmatic hydrothermal solution at the late stage of Beiyu granitoid plutonism , including striped tourmaline bearing rocks;(2)tourmaline formed by metamorphic fluids in Zhongtiao Group; (3) tourmaline formed by hydrothermal alteration at the stage of copper mineralization and occurring in the host rocks and the near ore rocks. The third type of tourmaline is characterized by veinlet form, fine grain size, rich MgO and poor FeO and mineral assemblage of quartz, calcite, biotite, pyrite and chalcopyrite. All these characteristics constitute important ore prospecting indicators.
出处
《岩石矿物学杂志》
CAS
CSCD
北大核心
1997年第2期160-169,共10页
Acta Petrologica et Mineralogica
