大别山典型燕山期侵入体中矿物成分特征及其地质意义

分析了大别造山带核部典型燕山期侵入体中的斜长石、黑云母和角闪石的化学成分和成因特点,并从矿物平衡角度讨论了典型侵入体岩石成因。结果表明：（１）石鼓尖侵入岩中,斜长石成分较稳定,共生角闪石和黑云母为岩浆平衡结晶的矿物;（２）天堂寨和九资河侵入岩中,部分斜长石和黑云母可能为深蚀残留矿物,角闪石属于火成岩区的新生矿物,可能为斜长石和黑云母发生融反应所形成;（３）三个侵入体的岩石均为岩浆成因。

Mineral compositions of typical Yanshanian intrusions in the Dabie Orogenic Belt and their geological implications

Chemical compositions and genetic characteristics of plagioclases, biotites and amphiboles of typical Yanshanian intrusions in the core of Dabie Orogenic Belt are presented. The petrogenesis of intrusive rocks is discussed in this paper according to the equilibrium of minerals. It is suggests that in the Shigujian pluton, the designations of plagioclases are 15 - 25, the plagioclases are all oligoclase; the biotites are Mg-biotites, and most of the amphiboles are edenitic amphiboles or edenite; paragenetic biotites and amphiboles were the crystallization of magama at the condition of equilibrium. In the Tiantangzhai and Jiuzihe plutons, the designations of plagioclases are 0 - 25 with apex numerals of 20 and 5 - 30 with apex numerals of 23, respectively. The plagioclases are mainly oligoclase, and some other ones are sodaclases, and the biotites are Mg-biotites. Most of the amphiboles are edenitic amphiboles or edenite. Some of the plagioclases and biotites were residuals of melting, there existed equilibrium between paragenetic biotites and amphiboles, and amphiboles were formed by melting reactions of plagioclases and biotites. None of the three intrusions was originated from "metamorphism or metasomatism", they were originated from magmatism.