Institute of the Earth's Crust, Siberian Branch of the Russian Academy of Sciences, 128 Lermontova St., Irkutsk, 664033, Russia.
J Environ Radioact. 2024 Sep;278:107509. doi: 10.1016/j.jenvrad.2024.107509. Epub 2024 Jul 30.
Time-dependent variations of Rn concentration (Q) in groundwater have been monitored for twelve years (2012-2023) at eight sites of groundwater discharge within the Baikal region in East Siberia, Russia. The concentrations of radioactive gas at different sites vary from 30% to 60% of average values (Q). The sampled waters are of three groups with Q ≈ 15 Bq/l (I), ≈30 Bq/l (II), and ≈50 Bq/l (II). Cluster analysis shows closest linkage between the two subgroups of group II due to similarity in the discharge mechanisms. Fourier analysis of periodic Rn behavior reveals major cycles of 365, 180, 126, and 30 days correlated with variations of air temperature and pressure, as well as with the patterns of groundwater discharge. In addition, radon anomalies are related with seismicity. Earthquakes are reflected in the radon field as three distinct anomaly types, occurring either subsequent to or prior to the seismic event. The anomalies responding to earthquake nucleation can be considered as precursors and used in earthquake prediction. The revealed trends make basis for a model designed to predict Q variations in groundwater of the area to 80% average efficiency. The external and internal factors that affect the concentration of radioactive gas in groundwater are linked in a hierarchic system and are classified according to the degree and type of their influence.
十二年来（2012-2023 年），我们一直在俄罗斯东西伯利亚贝加尔地区的 8 个地下水排泄点监测氡浓度（Q）的时间变化。不同地点的放射性气体浓度变化范围为平均值的 30%-60%（Q）。采样水分为三组，Q≈15 Bq/l（I）、≈30 Bq/l（II）和≈50 Bq/l（III）。聚类分析表明，由于排放机制相似，II 组的两个亚组之间存在最接近的联系。氡行为的傅里叶分析揭示了主要的周期为 365、180、126 和 30 天，与空气温度和压力的变化以及地下水排放模式相关。此外，氡异常与地震活动有关。地震在氡场中表现为三种不同的异常类型，要么发生在地震事件之后，要么发生在地震事件之前。对地震成核做出响应的异常可以被视为前兆，并用于地震预测。所揭示的趋势为该地区地下水 Q 变化的预测模型提供了基础，预测效率达到 80%。影响地下水放射性气体浓度的外部和内部因素在一个层次系统中相互关联，并根据其影响的程度和类型进行分类。
