2016年7月19日湖南涟源M_L 3.8事件类型判定

Determination of the type of Lianyuan M_L 3.8 earthquake in Hunan Province on July 19, 2016

通过地震波形及频谱特征与震源机制解结果,对湖南涟源ML 3.8事件类型进行分析判断,结果显示:本次事件波形与天然地震特征相似;频带分布较宽,集中在0—10 Hz,具有天然地震的频谱特征;主破裂面走向与地震烈度等震线长轴方向及附近断裂走向大体一致。此次事件处于华南地区新增粤闽赣湘NW向地震条带内边缘,故判定为天然地震。事件类型的正确判定,对湖南乃至华南地区的地震研究及地震活动趋势判断具有重要意义。

Basing on waveform analysis, frequency spectrum analysis and the result of focal mechanism, we analyzed and determined the type of Lianyuan M_L 3.8 earthquake in Hunan Province on July 19, 2016. The result shows that the seismic waveform is similar to that of natural seismic waveform; The frequency spectrum distribution is wide, it concentrated from 0 to 10 Hz, with the spectral characteristics of natural earthquakes; The main rupture surface is consistent to the long axis direction of the earthquake intensity isoseismal and consistent to the fault strike which is near the earthquake. As a result, we determined it is a natural earthquake. The earthquake is at an important part of the new northwest band of South China, the correct determination of its type will be of great significance to the future study of the earthquake and the tendency judgment of Hunan and even the whole South China area.