北京平原区隐伏碳酸盐岩地层划分及识别方法研究  

Geostratigraphic classification and identification method of hidden carbonate in Beijing plain area

作　　者：刘清晓 LIU Qingxiao(Beijing Institute of Geology,Beijing 100195,China;Beijing Institute of Engineering Geology,Beijing 100048,China)

机构地区：[1]北京市地质矿产勘查院,北京100195 [2]北京市工程地质研究所,北京100048

出　　处：《城市地质》2025年第1期39-46,共8页Urban Geology

基　　金：北京市地热资源和矿泉水动态监测及设备维护管理项目资助。

摘　　要：北京平原区隐伏碳酸盐岩地层的识别由于严重缺乏岩心等实物资料而成为地层划分中的难点。文章从研究岩石密度入手,在分析了十三陵山区出露基岩剖面的岩石化学数据后,发现不同时代、不同层位岩石的理化性质差异显著,并有一定的规律可循,是研究隐伏基岩地层的有效方法。研究表明:碳酸盐岩岩石密度大于2.80 g·cm^(-3),一般为中元古界;小于2.80 g·cm^(-3),一般为古生界。CaO含量大于30%,CaO/MgO大于8,Ti/Li大于100,这3项指标应是古生界碳酸盐岩的反映。上述标志得到了来自钻孔岩屑测量分析方面的支持。In stratigraphic division of the Beijing plain area,it is difficult to identify the hidden carbonate strata because of the serious lack of physical data such as core.Starting with the study of rock density,this paper analyzes the petrochemical data of exposed bedrock profiles in the Ming Tombs Mountain area,and finds that the physical and chemical properties of rocks in different times and strata have their own characteristics and laws.This is an effective method to study hidden bedrock strata.The results show that when the density of carbonate rock is more than 2.80 g/cm^(3),it is generally upper and middle Proterozoic strata and when less than 2.80 g/cm^(3),it is generally Paleozoic strata.CaO percentage at more than 30,CaO/MgO at larger than 8,and Ti/Li at larger than 100 are all indicative of Paleozoic carbonate strata.The above conclusions are also supported by borehole cuttings measurement and analysis.

关 键 词：碳酸盐岩 岩屑 密度测量 岩石化学分析 

分 类 号：P61[天文地球—矿床学]