The temporal variations of the instrumental seismicity (0.5 ≤ M_L ≤ 3.5) recorded in the Mingechevir area (Azerbaijan) between January 2010 to December 2018 and its relationship with the level variation of the water reservoir was analysed in this study. The monthly number of events was analysed by using the correlogram-based periodogram, the singular spectrum analysis (SSA) and the empirical mode decomposition (EMD), which are robust against the short size of the time series. Our results point out to the following findings: (1) quasi-annual periodicity was found in one SSA reconstructed component of the monthly number of events; (2) quasi-annual periodicity was found in one EMD intrinsic mode function of the monthly number of earthquakes. These obtained results could support in a rigorously statistical manner that the seismicity occurring in Mingechevir area could be triggered by the yearly cycle of the water level of the reservoir.

仪器地震活动性的时间变化（0.5≤M _L 本研究分析了2010年1月至2018年12月在Mingechevir地区（阿塞拜疆）记录的≤3.5）及其与水库水位变化的关系。通过使用基于相关图的周期图，奇异频谱分析（SSA）和经验模态分解（EMD）来分析每月事件的数量，这些事件对于时间序列的短长度具有鲁棒性。我们的结果指出了以下发现：（1）在每月事件数量的一个SSA重构部分中发现了准年度周期性；（2）在每月一次地震数的一种EMD固有模式函数中发现了准年周期。