明代生命损失型地震的时空分布特征及成因分析

利用史料记录建立了明代生命损失型地震的数据库，构建生命损失型地震等级序列、10 a尺度上生命损失型地震的频次序列和县次序列，再现明代生命损失型地震的时空分布特征，探讨了生命损失型地震发生及导致人口死亡的时空差异原因。结果表明：（1）从明初到明末，生命损失型地震等级强度有逐渐扩大的趋势。（2）明代前期处于生命损失型地震发生较少的稳定时期；明代中后期处于生命损失型地震发生较多的波动时期。明代生命损失型地震发生频次存在明显的周期性变化特征。（3）生命损失型地震在明代大部分区域皆有分布。灾害重心随时间变化发生移动，由西南到中部再到华北、华东。（4）明代地震频繁的原因除地球本身因素外，太阳活动通过影响气候变化，进而间接影响地壳活动。气候寒冷与干旱和地震有较好的对应关系。明代后期生命损失型地震导致死亡人数大量增加，与明代经济发展，人口密度逐渐增长有关；不同地区生命损失型地震导致的死亡人数不同，且死亡人数与地震频发地区是否处于板块之间的活动构造带和人口分布密度有关。

Temporal and spatial distribution and cause analysis of life-loss earthquakes in the Ming Dynasty

The database of life-loss earthquakes in the Ming Dynasty is established based on using historical records, and the intensity, frequency and epicentral county of life-loss earthquakes are ranked on a 10 a scale . This paper analyses the temporal and spatial distribution characteristics of life-loss earthquakes in the Ming Dynasty. The causes of life-loss earthquakes and differences of the death toll in the time and space are discussed. The results show:(1) From the beginning to the end of the Ming Dynasty, the intensity of life-loss earthquakes gradually increased.(2)The early time of the Ming Dynasty was in a period of stable epidemic with less life-loss earthquakes. The middle and late Ming Dynasty was in a period of frequent fluctuations in the epidemic. There were obvious periodic variations in the frequency of the earthquakes causing death in the Ming Dynasty.(3) The life-loss earthquakes were distributed in most areas of the Ming Dynasty. The epicentral area of the disaster moves with time, from southwest to central of China then to north and east China.(4) The reasons for more earthquakes occurring in the Ming Dynasty included the factors of the earth itself and solar activity. Solar activity indirectly affected crustal activity by influencing climate change. Climate of cold and drought has a good correspondence with the earthquakes. The number of deaths caused by life-loss earthquakes in the late Ming Dynasty increased significantly, which should be related to the gradual development of the Ming Dynasty economy, when population density increased. The number of deaths caused by life-loss earthquakes in different regions is different. On the one hand, seismic frequent areas are in active tectonic zones between plates, and on other hand, they should be related to population distribution.