旱涝交替下陕西地震时空分布规律与相关因子探究

Study on the Spatial-temporal Distribution of Earthquakes in Shaanxi and Their Driving Forces under the Alternation of Drought and Flood

为了研究在旱涝交替下陕西省地震时空分布与其驱动因子的关系,首先采用年尺度同步分析了旱涝交替下地震活动的变化特征;进而运用Mann-Kendall法和启发式分割算法对陕西省区域旱涝交替下地震震级与气象因子进行趋势分析以及变异点诊断;最后,运用交叉小波变换分析了其相关关系。结果表明:在年尺度上,旱涝交替下地震活动表现出在地震活跃期(平静期),旱涝次数呈多发性(稀少性)的特征;地震最大值和降水序列较为平稳,没有出现变异点;地震最小值和气温序列发生突变,其分别在地震活动的活跃期与平静期的开始时刻,且两个序列分别呈下降趋势和上升趋势;地震震级对降水和气温因子的敏感程度不同,但对降水的敏感程度更大。

In order to study the relationship between the spatial-temporal distribution of earthquakes in Shaanxi province and their driving factors under the alternation of drought and flood,this study first uses the annual scale synchronous analysis to analyze the variation characteristics of seismicity;then applies the Mann-Kendall method and heuristic segmentation algorithm to the analysis of earthquake magnitude trend and their meteorological factors and diagnosing the variation points under the condition of alternate drought and flood in Shanxi province;finally,the cross small method is used to analyze the correlation of wave transformation.The results show that on the annual scale,the seismicity under the alternation of drought and flood reflects the characteristics of multiple occurrence(rarity)in the seismicity active period(quiet period),the relatively stable maximum value of earthquake and the precipitation sequence without any variation point;the the minimum earthquake value and sharp mutation in temperature sequence,with which a descending curve and ascending curve can be obviously observed respectively at the beginning of the active period and the quiet period of seismicity;the sensitivity of earthquake magnitude to precipitation and temperature varies,but it is more sensitive to precipitation.