The eastern margin of the Tibetan Plateau has been characterized by frequent disastrous earthquakes, which has induced changes in groundwater such as variations in isotopes, ions, and dissolved gases. In this study, the fluctuation of groundwater radon recorded at six different monitoring stations from 2009 to 2018 was analyzed. With the statistical approach (the residual signal processing technique and the Hurst exponent estimates), groundwater radon variations caused by seismic events were unraveled, reflecting regional stress status changes. The results of this study indicated that (1) groundwater radon exhibits distinct differences between the eastern margin of the Sichuan-Yunnan Block and the South China Block; (2) the precursory anomalies of groundwater radon are principally categorized into three types: positive, negative, and dual behaviors; (3) the relatively low level of the groundwater radon results from the underlying rock masses resisting the compressional stress and the locking on the Xianshuihe fault, the Anninghe fault, and the Zemuhe fault. Additionally, the seismic response zone of each monitoring station was delineated using historical seismic precursors.

青藏高原东缘灾害性地震频发，引起地下水同位素、离子、溶解气体变化等变化。本研究分析了 2009 年至 2018 年六个不同监测站记录的地下水氡的波动情况。通过统计方法（残余信号处理技术和赫斯特指数估计），地震事件引起的地下水氡变化被解开，反映了区域应力状态的变化。研究结果表明：（1）川滇地块东缘与华南地块地下水氡含量存在明显差异；(2)地下水氡前兆异常主要分为正、负、和双重行为；(3) 地下水氡水平较低是由于下伏岩体抵抗压应力和对鲜水河断层、安宁河断层和则木河断层的锁定造成的。此外，每个监测站的地震响应带都是使用历史地震前兆来划定的。