In the western part of the South Baikal Basin, spatial-temporal distribution of earthquake epicenters shows quasi-periodic seismic reactivation. The largest earthquakes that occurred in 1999 (M_W = 6.0) and 2008 (M_W = 6.3) fall within seismic intervals of 1994–2003 and 2003–2012, respectively. In the seismic interval that began in 2013, the ²³⁴U/²³⁸U activity ratio (AR) in groundwater was monitored assuming its dependence on crack opening/closing that facilitated/prevented water circulation in an active boundary fault of the basin. Transitions from disordered, high-amplitude fluctuations of AR values to consistent, low-amplitude fluctuations in different monitoring sites were found to be sensitive indicators of both small seismic events occurring directly on the observation area, and of a large remote earthquake. The hydroisotopic responses to seismic events were consistent with monitoring data on deformation and temperature variations of rocks. The hydroisotopic effects can be applied for detecting a seismically dangerous state of an active fault and prediction of a large future earthquake.

在贝加尔湖南部盆地的西部，地震震中的时空分布表明准周期性地震活动。发生在1999年最大地震（中号_{w ^} = 6.0）和2008（中号_{w ^} = 6.3）落在1994〜2003年分别和2003至2012年，地震间隔内。在2013年开始的地震间隔中，假设地下水对²³⁴ U / ²³⁸ U活度比（AR）的依赖性取决于裂缝的开/关，而裂缝的开/关有利于/防止了盆地活动边界断层中的水循环，因此对其进行了监测。从AR的无序，高振幅波动过渡人们发现，在不同的监测地点，一致的低振幅波动的值既是直接发生在观测区的小地震事件，又是大地震的敏感指标。同位素对地震事件的响应与岩石变形和温度变化的监测数据一致。氢同位素效应可用于检测活动断层的地震危险状态并预测未来的大地震。