论文部分内容阅读
北京密云地区太古界变质岩系以其丰富的铁矿资源和变质作用的特征曾引起多方面的注意,许多地质工作者先后进行过大量工作,但对矿物学的系统研究却比较缺乏。笔者在密云水库东部及南部的小槽、芦头、半截峪等矿区对含铁岩系的辉石、石榴石及磁铁矿进行了较系统的研究,进而探讨铁矿成因及变质作用的温度、压力条件。本区位于燕山台褶带密怀隆起的东部。出露地层为太古界密云群沙厂组及大槽组。半截峪铁矿及
The metamorphic rocks in the Miyun area of Beijing have attracted many attentions due to their rich features of iron ore resources and metamorphism. Many geologists have carried out a great deal of work in succession, but systematic researches on mineralogy are scarce. The author conducts a systematic study on the pyroxene, garnet and magnetite in iron-bearing rock series in the small trenches, Luotou and Ban-yu formations in the eastern and southern parts of the Miyun Reservoir and further explores the temperature of the genesis and metamorphism of the iron ore Pressure conditions. The area is located in the Yanshan Taiwan folds Mihuai uplift in the east. Exposed stratum is the Archean Miyun Sands plant group and large groove group. Half cut iron ore and