利用现代小地震分布研究1861年辽宁普兰店东6级地震的震中位置和发震构造

1861年7月19日发生在辽宁省普兰店东的6级地震在不同目录及研究中给出的震中位置有很大差异。总结以往对此次地震震中位置的研究,大致涉及4个不同地点。本文对分布在该区的现代小震进行重新定位,结果表明,小震活动在普兰店以东地区形成明显的北西向优势分布。综合分析1861年普兰店东6级地震的主要破裂方向为北西向,受北东向金州断裂北西向普兰店长海断裂的双重控制。

Research about the east of Pulandian M 6 earthquake and its causative structure in 1861 in Liaoning Province by the distribution of modern small earthquakes

On July 19, 1861, an earthquake of M 6 occurred in the east Pulandian in Liaoning Province, which is located at quite different epicenter in different catalogs. The summary of for- mer study involves generally four different position. In this paper, we use the Double-Differ- ence （DD） method to relocate small earthquakes from the study region. The results show that the predominant distribution direction of small earthquakes in the east of Pulandian area is in NW orientation. Comprehensive analysis indicates that the main fracture direction of the east of Pulandian M 6 earthquake in 1861 is NW that may be dual controlled by both Jinzhou NE fault and Pulandian-Changhai NW fault.