2014年鲁甸MS6.5地震后地质灾害发育分布特征

Development and Distribution Characteristics of GeologicalHazards after the 2014 Ludian MS6.5 Earthquake

摘要:

2014年云南鲁甸“8·03”M_S6.5地震造成了重大人员伤亡和财产损失，诱发了大量滑坡、崩塌、泥石流等地质灾害。基于对鲁甸县龙头山幅（G48E006006）地质灾害调查数据和对典型地质灾害的剖析，震后地质灾害发育分布有特征如下：（1）震后地质灾害较震前成倍增长，震前地质灾害多以中小型浅层崩滑为主，地震诱发了诸如甘家寨、红石岩等大型—特大型滑坡、崩塌，大量沟谷崩滑堆积物为泥石流储备了丰富的物源；（2）震中高烈度区域地质灾害密度大，沿发震断裂带NNE—NE向构造密集发育，震中区龙头山镇地质灾害发育最为集中；（3）地质灾害呈带状分布，明显受控于河流水系（牛栏江、沙坝河、龙泉河等）、公路（昭巧二级公路、沙乐公路）等线性地貌单元和线性工程，人类活动影响明显。

Abstract:

The Ludian M_S6.5 earthquake on August third,2014,caused heavy casualties and property losses and induced a large number of landslides,collapses,and secondary geological disasters.Based on a geological disaster survey of Longtoushan map (G48E006006) in Ludian County and analysis of typical geological disasters,development laws and distribution characteristics of geological hazards after the earthquake are revealed in this paper:(1) Most of the geological disasters before the earthquake are mainly medium and small shallow landslides and collapses.After the earthquake,large and extra-large landslides and collapses were induced,such as Ganjiazhai and Hongshiyan,and a large number of valley deposits were formed; (2) The distribution of geological disasters is concentrated in high-intensity areas of epicentral region,especially in Longtoushan town and intensively developed along the NNE-NE trending seismogenic fault zone, the geological disasters develop most intensively in epicentral area; (3) The geological disasters show a zonal distribution feature,obviously controlled by linear geomorphic units and linear engineering,such as river systems (Niulan River,Shaba River,and Longquan River) and highways (Zhaoqiao road and Shale road), and the impact of human activity is striking.