Characteristics of karst development on the top of the plateaumountain:Taking the ShikaMountain as one example

What is the situation of karst developed on the bare rock high mountain limestone planation above the elevation of 4，000m ? What are the behaviors of the karst process? This paper takes the Shika Mountain in Shangri-La, Yunnan Province as case study, with the intention of answering these questions through field investigation and analysis of the field findings. It is observed that in the 2.4 km2 survey area above the altitude of 4,000 m, there are more than 118 caverns in the Carboniferous limestone and 6 near horizontal karst caves. The results of high density electrical resistivity (ER) show that the underground karst is usually characterized by the zones with low ER, which indicates surface isolated sink holes and dolines become connected at the depth of 50-60 m, and the connected area became larger at the depth of 100-180 m. In groundwater system, the study area is located in the vertical precipitation recharge area. The upstream limestone and downstream mudstone have an influence on the runoff path and discharge manor of the water. As a result, there are 12 karst depressions and 4 spring points observed on the surface. In addition, the groundwater in the area is shallow, with a fast discharge. These characteristics of karst development provide a geological basis for site planning and utilization on the plateau surface.