Abstract:
Objective The Gonjo area is located in the suture zone of the Jinsha River plate in eastern Xizang. The landslide disaster is large in scale, high in frequency and widely distributed, which has a serious impact on the safety of local houses, roads and bridges. At present, the research on landslides mostly focuses on the engineering geological parameters after the occurrence of landslides, and there are few studies on the basic geological characteristics of landslides. The basic geological characteristics of typical landslide can provide theoretical support for interpreting the disaster mechanism and disaster prevention of landslides.
Methods In this paper, through the collection of previous research data and the field geological survey of the Sela landslide, starting from the basic geological point of view, the rock lithology characteristics and structural characteristics of the landslide are analyzed, and the reasons for the frequent occurrence of landslides in this area and the damage characteristics of landslides are summarized.
Results This study believes that the frequent occurrence of landslides in this area is the result of the combined influence of internal factors such as stratum lithology and a series of structures developed by the landslide itself and external factors such as earthquakes and rainfall.
Conclusions The development strata of the Sela landslide belong to the Jinshajiang tectonic mélange belt as a whole, and the lithology is complex. It is mainly composed of various schists and gneiss matrices of the Permian−Early Triassic Gangtuo Formation and a small amount of marble and feldspar quartz sandstone. The rock is relatively weak and prone to deformation. The landslide structure is characterized by the superposition of ancient structure and new structure. In addition, a large number of tensile fractures are developed at the trailing edge of the landslide, and the internal joints of the rock itself are developed and the occurrence is changeable, which further reduces the rock strength. Secondly, there are multi−stage activities in the new and old faults in this area. The lithology of the fault surface is different and the weak interlayer is developed at the fault surface. The stability of the landslide is greatly affected by the evolution strength of the weak interlayer, which lays a hidden danger for the occurrence of the landslide.