则木河断裂带灾害效应及致灾模式研究

STUDY OF DISASTER EFFECT AND DISASTER MITIGATION MODEL OF ZEMUHE FAULT ZONE

则木河断裂带位于青藏高原东南缘,川滇菱形地块东边界的突起上,为大型左旋走滑活动断裂,因其所处的特殊构造部位、强烈的地壳形变与断裂活动,从而具有地形复杂、构造强烈、地震活跃、次生地质灾害严重的特点。大箐断层在则木河断裂带次级断裂中活动速率最大,地处断陷河谷盆地和大箐梁子隆起区,且大箐梁子为1850年7.5级地震震中和断层枢纽运动中心,河谷保留冰川活动的遗迹,地质灾害发育,因此将大箐断层作为研究对象具有良好的典型性和代表性。通过现场调查,依据孕育地灾的地质背景条件,斜坡在地震动力作用下的响应特征和斜坡失稳的成因机制,将断裂致灾模式分为3大类,7亚类,共15种类型。大类的划分主要依据地质灾害的类型,亚类考虑灾害动力响应过程及斜坡失稳演化模式,是斜坡失稳破坏最显著的差异;小类的划分主要依据坡体的地质结构,是灾害失稳具体形式上的差异。本文较为系统地揭示了大箐断层地质灾害的成因机制及致灾模式。

The Zemuhe fault zone has large sinistral strike slip faults,which locates at the southeastern margin of the Tibetan Plateau and the eastern boundary of Sichuan-Yunnan rhombic block projections. It has the characteristics of complex terrain and strong tectonic earthquake,active and serious secondary geological disasters due to its special tectonic position,crustal deformation and faulting. The Daqing fault is located in the faulted valley basin. The Daqing Liangzi uplift area is the largest in the secondary fault of the Zemuhe fault zone. The Daqing Liangzi is the earthquake center of the magnitude 7. 5 earthquake in 1850. The river valley retains the remains ofglacier activities,geological disaster development. So the Daqing fault as a research object has a good typical and representative. According to the geological background condition of the disaster,the response characteristics of the slope under the action of the earthquake power and the mechanism of the slope instability,the fault disaster pattern are divided into 3 categories,7 sub-categories and 15 types. The division of the categories is mainly based on the types of geological disasters,sub-categories to consider the disaster dynamic response process and slope instability evolution model,which is the most significant difference in the failure of the slope instability. The sub-class division is mainly based on the slope of the geological structure and stability of the form of the difference. This paper systematically reveals the genesis mechanism and the disaster model of the geological fault of Daqing fault.