The relevance of hydrogeological precursors (HGPs) study is justified by the need to obtain reliable information about the spatio-temporal manifestations and the relationships of HGPs with the parameters of subsequent earthquakes for seismic forecasting. In the review the data on repeated manifestations of HGPs before strong earthquakes obtained from long-term observations in five deep wells on the Kamchatka Peninsula (Far East of Russia) are presented. The analysis of the correlation of HGPs occurring in several wells is carried out in comparison with earthquake parameters characterizing both earthquake sources (magnitude, linear size of the source) and the impact of earthquakes in the area of wells (specific energy density in wave, intensity of shaking). It is shown that the manifestation of HGPs in several wells is observed before earthquakes with M_w = 6.6–7.8 at epicentral distances up to the first hundreds of km to observation wells in the near and intermediate zones of the sources with the ratio of the epicentral distances and the source sizes no more than 1–5. A feature of our study was the use of certain types of HGPs in water-level changes for predictive assessments of the strong earthquakes in the Kamchatka Peninsula. The review presents precursors in water-level changes detected in real time and the corresponding earthquake forecasts, which were recognized as successful according to the conclusions of the expert council on earthquake prediction.

水文地质先兆（HGPs）研究的相关性是由于需要获得有关时空表现以及HGPs与后续地震参数之间的关系以进行地震预报的可靠信息而证明的。在审查中，提供了从堪察加半岛（俄罗斯远东）的五个深井的长期观测获得的强地震之前HGP重复表现的数据。与表征地震源（震级，震源的线性大小）和地震对井区的影响（波的比能量密度，强度）的地震参数进行了比较，分析了多口井中发生的HGP的相关性。摇晃）。中号_w = 6.6–7.8，在震源附近和中间区域至震源的前数百公里处的震中距离处，震中距离与震源尺寸之比不超过1-5。我们研究的一个特点是在水位变化中使用某些类型的HGP对堪察加半岛的强地震进行预测评估。审查提出了实时检测到的水位变化的前兆以及相应的地震预报，根据地震预报专家委员会的结论，这些预报被认为是成功的。