云南M≥7.6级地震伤亡因素的探讨

DISCUSSION ON THE CAUSES OF THE CASUALTIES OF M≥7.6 EARTHQUAKES IN YUNNAN

通过云南M≥7.6级地震震亡分布的统计,研究大地震的伤亡分布规律,寻找影响伤亡的主要原因。结果表明,震亡人数主要分布在Ⅷ度以上烈度区,这一区域的震亡人数占震亡总数的94%以上,其中极震区占到70%以上。调查分析认为:在震级相近的情况下,震区地质构造、地形地貌是影响地震烈度的因素;房屋、人口密度、发震时间是震亡人数的重要影响因素;在未来的大地震中,人口密度大的断裂带及其附近是应急救援和医疗救护的重点区域,在断裂带及其附近盆地内的震亡人数比非盆地震亡人数多,要投入更多的救援和医疗救护力量。

Using the distributed statistics of the casualties caused by M≥7.6 earthquakes in Yunnan, the authors have studied the regularity of the distribution of the casualties in the great earthquake events and discussed the main factors affecting the casualties. They find that the people died in the 8 intensity area account for more than 94% of the death toll and the ones died in the meizoseismal area are more than 70% of the total. When the magnitudes were approximate to each other, the geological structure and the to earthquake - stricken area became the main factors affecting the earthquake intensity. Quality of the buildings and population density in the earthquake - stricken area and the original time of the earthquake were the decisive factors for the death toll in the earthquake events. The earthquake belts and their neighboring regions with dense population are the key area for the emergency rescue medical aid. The death toll in the basin in the earthquake belt or nearby is more than the ones in other areas, so more emergency rescue and medical aid should be provided in this area.