土壤氡气测量与CSAMT测量在铜冶店——孙祖断裂勘查中应用

Application of Soil Radon Measurement and CSAMT Measurement in the Exploration of TongyedianSunzu Fault

摘要:

土壤氡气测量主要应用于探测断层的位置、产状、性质、活动性并应用于地震监测预警，与CSAMT测量联合使用可以相互补充、相互印证。本文在铜冶店孙祖断裂雪野段布设3条测线，分别进行土壤氡气测量和CSAMT测量，并在测线推测的氡异常带附近取地下水样品进行氡气测试：通过对各测线氡异常带分布特征分析，结合CSAMT测量反演生成的视电阻率断面解译结果，推断铜冶店孙祖断裂在雪野地区形成数条近平行的次级断裂，呈现随着与主断裂距离越远构造应力逐渐消减，其活动强度越弱，氡异常幅度亦弱的规律。本次研究采取土壤氡气测量与CSAMT测量联合探测断裂取得良好效果，可在各类地质勘查工作中推广使用，尤其在活动断裂勘查方面尤为有效。

Abstract:

Soil radon measurement is mainly used to detect the location, occurrence, nature and activity of faults. It is also used in earthquake monitoring and early warning. Combining with CSAMT measurement, it can complement and confirm each other. In this paper, three survey lines are set up in Xueye section of Tongyedian-Sunzu fault to conduct soil radon measurement and CSAMT measurement respectively, and groundwater samples are taken near the radon anomaly zone inferred by the survey lines to conduct radon measurement. Through analyzing the distribution characteristics of radon anomaly zone of each survey line, combining with the interpretation results of apparent resistivity section generated by CSAMT measurement inversion, it is inferred that Tongyedian-Sunzu fault is formed in Xueye area. Several nearly parallel secondary faults show the rule that with the distance from the main fault, the tectonic stress gradually decreases, the activity intensity is weaker, and the radon anomaly amplitude is weaker. In this study, the combination of soil radon measurement and CSAMT measurement has achieved good results, which can be widely used in all kinds of geological exploration, especially in the exploration of active faults.