辽宁彰武大四家子珍珠岩矿床特征及成因探讨

Discussions on geological characteristics and genesis of Dasijiazi perlite deposit in Zhangwu,Liaoning Province

根据前人研究成果及本次勘探工作,综合分析了大四家子珍珠岩矿床地质特征。珍珠岩矿体赋存于下白垩统义县组流纹岩中,呈似层状、透镜状展布,常与膨润土、沸石共生出现。通过对矿石中主要化学成分含量分析,了解矿石中膨胀倍数的变化规律;通过X衍射及差热分析结果系统研究,了解了珍珠岩中矿物成分与膨胀倍数关系和矿物中水的存在形式。在此基础上探讨了珍珠岩矿床的成因,系酸性岩浆沿构造部位喷发或喷溢至水下或地表,温度迅速骤降,急骤冷却形成的。

According to the previous research results and this exploration work,the paper has comprehensively summarized the geological characteristics of Dasijiazi perlite deposit.The perlite orebody is hosted in the rhyolite of Early Cretaceous Yixian Formation.It is semi-layered,layeroid and lenticular.The perlite often appears in association with bentonite and zeolite.Based on the analysis of the main chemical composition content of ores,the variation regularity of expansion multiples is studied in the paper.Through the systematic research of X-ray diffraction pattern and differential thermal analysis,the relationship between mineral composition and expansion multiples and the water form in mineral is also studied in the paper.On the basis of these results,the genesis of perlite deposit is inferred for that acid magma erupts or spills along the structural position into the water or the surface,and the temperature drops rapidly.The perpite deposit is formed for the rapid cooling.