北京平原区隐伏断裂与氡浓度响应关系

北京地区隐伏断裂发育,NW及NE向断裂相互交汇,成为未来可能发生地震的构造。为了研究活动断裂与土壤氡浓度的响应关系,本次对北京平原区NW和NE向2条剖面进行了氡浓度测量。通过测试分析,基本查明了隐伏构造与土壤氡浓度的对应关系以及影响土壤氡浓度的相关地质因素。研究表明,活动断裂存在的区域氡浓度明显高于周边区域,且在构造复杂与活动性强的断裂区域氡浓度值变化更为明显;新生界厚度对氡的散逸强度存在一定的制约,北京地区新生界厚度与氡浓度水平成正相关;不同成土母质核素比活度不同,对区域氡浓度背景值亦存在影响。本次研究成果确定了隐伏断裂与土壤氡浓度的对应关系,以及新生界厚度和不同成土母质土壤对土壤氡浓度的影响,为今后在平原区开展隐伏断裂调查及氡浓度研究工作有重要借鉴和指导意义。

Relationship between concealed faults and radon concentration in plain areas of Beijing

Concealed faults are developed in the Beijing area. They intersect with NW- and NE-trending faults, forming a potential tectonic background of earthquakes in the future. To study the relationship between active faults and the radon concentration in soil, this study measured the radon concentration of two profiles (NW- and NE-trending) in plain areas of Beijing. Through tests and analysis, this study roughly ascertained the relationship between concealed structures and the radon concentration in soil, as well as the geological factors influencing the radon concentration of soil. The results show that the radon concentration in areas with active faults is significantly higher than that in the surrounding areas, and the radon concentration in areas with complex structure and highly active faults changes more noticeably. The depth of Cainozoic strata constrains the dissipation of radon to a certain extent, and there is a positive correlation between the depth of Cainozoic strata and the radon concentration in soil. The specific activity of radionuclides in parent rocks with different soil quality also affects the background value of regional radon concentration. The results of this study determined the relationship between concealed faults ahe specific activity of radionuclides in parent rocks with different soil quality also affect the background value of regional radon concentration. The results of this nd the radon concentration in soil and identified the influence of the thickness of Cainozoic strata and parent rocks with different soil quality on the radon concentration in soil, thus serving as an important reference and guidance for the surveys of concealed faults and the research on radon concentration in plain areas of Beijing in the future.