"6" Landslide in Wukou Formation, Shanhou Village, Wangcun Town, Xiuning County, Huangshan City, Anhui Province

2011June 5th, affected by continuous heavy rainfall for several days, the front edge of a slope of Wukou Formation in Shanhou Village, Wangcun Town, Xiuning County collapsed in many places, and many arc-shaped tensile cracks appeared in the middle and upper parts. The width is 0. 5 ~ 5 cm, and there is a sinking sill with a height difference of 2 ~ 10 cm, which directly threatens the life and property safety of the people in the county-level highway and the wharf group in front. After receiving the report, the village cadres of Wangcun immediately organized personnel transfer. Due to the timely transfer, 38 people were successfully avoided.

1 1: 30, the slope slipped, and the geographical coordinates are: east longitude117 50' 49 ",north latitude 29 39' 52". After field investigation, it is considered that the landslide is a traction type of middle-earth landslide. The plane shape of the landslide is fan-shaped, with a length of 38m, a bottom width of 40m, a thickness of 6 ~ 12m and a volume of 15000m3. The slope toe elevation is 286m, the slope top elevation is 308m, the relative height difference is 22m, and the main landslide direction is 355m m.

The landslide area belongs to the low mountain landform in southern Anhui with strong erosion. The landslide is located on the north slope of the mountain, and the foot of the slope is eroded by running water. The slope is steep, the natural slope is 5 ~ 45, the lower part is slightly steep, the upper part is gentle, and the slope is 5 ~ 20. According to the field investigation, the slope is silty clay containing gravel formed by residual slope accumulation, and its thickness is 3 ~ 16m. Gravel is phyllite weathered rock of Mukeng Formation in Mesoproterozoic, with a content of 5% ~ 15%. The soil structure is loose and the stability is poor. The underlying bedrock is phyllite with poor weathering resistance. The average thickness of fully weathered-strongly weathered layer is greater than 10m, and the shear strength is low. The front edge is excavated for highway construction, and an artificial high and steep slope is formed after excavation, with the maximum height of about 16m and the slope greater than 70. The cause of landslide can be attributed to the influence of stratum lithology, cutting slope ahead and rainfall.

Figure 1 Warning signs on landslide site

Fig. 2 Panorama of Landslide

2 Monitoring and emergency hedging

2. 1 monitoring and early warning

Since the flood season, under the unified arrangement and deployment of Xiuning County, Wangcun Town has actively organized cadres to go deep into various village groups, conducted a serious investigation on hidden dangers of geological disasters and high and steep slopes, found hidden dangers, and kept cadres in the village day and night to guard against death and ensure the safety of people's lives and property.

/kloc-On the night of June in 0/4, the rainstorm struck again, and the village cadres behind the mountain held their posts and mobilized cadres to prepare for emergency rescue. 15438+065438+At 0: 30 on May 5, after receiving a report from the masses that stones were rolling down the mountain, the village cadres quickly rushed to the scene. After investigation, they found that there were cracks in the mountain, roads, shops and restaurants in front, many people in the house and pedestrians on the road. Town and village cadres immediately report the situation to their superiors.

2.2 Emergency hedging

After discovering the danger, the town and village cadres immediately launched an emergency plan to transfer 3/kloc-0 people who were threatened in shops and restaurants and 7 pedestrians who were passing, and left them at the intersection, prohibiting people from passing. Just as the masses moved to the village Committee, there was a loud bang, and the landslide washed away the house below, flooded the pigsty and broke the telephone pole. Due to timely warning and rapid avoidance, casualties were avoided.

2.3 Subsequent disposal

After receiving the disaster report, the Xiuning county government immediately organized land, transportation, health and other departments and geological experts to rush to the scene to guide the rescue and relief work, set up warning lines, set up warning signs, and implemented a 24-hour rotation system for village cadres to keep an eye on the changes in the disaster situation at any time, prohibiting pedestrians and vehicles from passing. Township cadres organize militia to clean up the landslide site to minimize disaster losses.

Figure 3 CCTV reporters interviewed the affected people.

Figure 4 Cadres and the masses clean up the landslide site

3 Experience and Enlightenment

Leaders' attention is the premise of doing a good job in geological disaster prevention and control. 20 1 1 At the beginning of the year, a meeting was held to deploy the prevention and control of geological disasters, and a target responsibility letter was signed at all levels to clarify the prevention and control responsibilities and tasks. During the flood season, the county magistrate was established as the team leader, and the main person in charge of relevant departments was a member of emergency headquarters geological disaster rescue and relief, who was fully responsible for the management, prevention and emergency work of geological disasters in the county. Villages and towns also set up corresponding organizations according to the actual situation, and take the overall responsibility of the "top leaders" in administration. Leaders at all levels attach great importance to it and implement their responsibilities step by step, which is the prerequisite for the success of this hedging.

Strengthening foundation is the key to the prevention and control of geological disasters. The basis of prevention and control of geological disasters lies in the grass-roots level of villages and towns, and the key lies in the monitoring and inspection of hidden dangers. In Xiuning County, technicians should patrol and investigate hidden dangers every year, determine key prevention and control areas, scientifically formulate prevention and control plans and emergency plans in combination with the disaster prevention situation and weather forecast throughout the year, strictly implement disaster prevention responsible persons and monitoring personnel, set up emergency teams, prepare sufficient emergency materials, and deal with them calmly and quickly in case of danger.

Group prevention and treatment is the guarantee of geological disaster prevention and control. Xiuning County insists on the publicity and training of mass geological disaster prevention knowledge, and constantly improves the network of group monitoring and prevention. During the flood season, the County Bureau of Land and Resources and the Meteorological Bureau jointly carry out the early warning and forecasting of geological disasters, and publish forecast and early warning information through electronic display screens, mobile phone text messages, telephones, networks and other channels every day. In order to enhance the people's awareness of disaster prevention and mitigation, various forms of emergency drills have been carried out in various places in light of the actual situation.

(This part of basic information is provided by Anhui Provincial Department of Land and Resources and edited by Xu Yongqiang)