Main achievements and benefits achieved

(a) basically solve the problem of drinking water for people and livestock and farmland irrigation in gongyi city.

Twenty exploration-production demonstration wells were implemented in Gongyi, Henan Province, with a total drilling footage of 3,453.4 m and a total water inflow of 22,323.4 t/d, which directly solved the drinking water problem of 26,654.38 people and 5,000 large livestock and the irrigation problem of13,040 mu of farmland (Table 654.38+0-3).

Table 1-3 Statistics of emergency drought-resistant drilling results in Gongyi, Henan Province, Nanjing Geological Survey Center

(2) The hydrogeological conditions and the present situation of groundwater development and utilization in gongyi city are basically found out.

Due to the relative lack of surface water resources in gongyi city, Henan Province, the development and utilization of groundwater resources plays an important role in gongyi city. In recent years, the average groundwater exploitation (water supply) is123.88 million m3.

There are three types of groundwater in gongyi city, Henan Province: loose rock pore water, carbonate fissure karst water and bedrock fissure water. According to the hydrochemical characteristics of groundwater, it can be roughly divided into four hydrochemical types: Mangshan hilly area and Yellow River terrace area (HCO3-Ca. Sodium magnesium type and calcium bicarbonate type. Mg.Na type), the terrace of Luo Yi River and the piedmont plain area behind the terrace (HCO3-Ca. Mg type), southeast clastic rock distribution area (HCO3-Ca. Na type)

On the whole, the deep groundwater level in gongyi city shows a downward trend, such as the northern loess hilly area and piedmont slope plain area south of Luo Yi, and the hilly and mountainous areas such as Mihe, Xinzhong, Xiaoguan, Dayugou, Walnut Garden, Shecun, Jiajinkou and Xicun.

Groundwater in gongyi city basically meets the hygienic standard for drinking water (GB5749—2006).

(3) The occurrence regularity of groundwater and the types of water storage structures in gongyi city are basically found out.

Groundwater in gongyi city, Henan Province mainly occurs in loose rock pores, carbonate fracture karst and bedrock fractures. According to the depth, the pore water of loose rocks can be further divided into two types: shallow water (60m shallow) and deep water (60 ~ 300 m). The water-rich areas of shallow water-bearing formation are distributed in the Yellow River beaches and terraces, Luo Yi Valley, Sishui Valley, terraces and hillsides, and the success rate of well setting is high. The water-deficient areas of shallow aquifer group are distributed in Mangshan, piedmont inclined plain and piedmont loess hilly area, such as Kangdian, Shayugou-Beishankou-Zhitian-Luzhuang area, with large loess thickness and low success rate of exploration well. Deep pore water-rich areas are distributed in gongyi city, Beishankou-Shayugou, south of Huiguo Town-Zhitian and north of Nianzizhuang-Luokou, and the success rate of well layout is high. The middle area of deep pore water volume is located in the south of water-rich area, the east of Zhan Jie-Yu Ying South District and the west of Luzhuang-Xicun District, so the success rate of well sitting is high. In hilly areas, a moderate amount of carbonate fissure karst water is distributed in Xinzhong-Mihe area, Walnut Garden and Shecun-Jiajinkou area in the east. The aquifer is Cambrian and Ordovician limestone, dolomite limestone and dolomite, and the success rate of well construction is high. However, due to mining, the regional groundwater level drops, some bedrock aquifers are drained, and mine drainage makes the success rate of well drilling in some areas low. The bedrock fissure water in hilly areas is distributed to the north of the main peaks of Songshan Mountain and Wu Zhiling, to the north of Mihe-Xiaoguan-Dayugou, and to the north of Shecun-Guandi Temple. The groundwater is poor and the success rate of well drilling is not high.

The investigation shows that it is very important to distinguish the occurrence structure and conditions of groundwater in the process of finding groundwater. It is found that there are five types of groundwater storage structures in gongyi city, Henan Province: karst or contact karst storage structure, loose rock storage structure, fractured storage structure, monoclinic storage structure and bedrock weathering crust sheet storage structure. Among them, the water storage structures of loose strata can be further divided into two kinds of water storage structures: river terrace loose strata and piedmont inclined plain loose strata, and fault water storage structures can be further divided into three kinds of water storage structures: fault lateral influence zone, fault intersection influence zone and fault fracture zone.

(4) The zoning of groundwater development and utilization in gongyi city is compiled.

According to the spatial distribution of groundwater in the area and the distribution law of groundwater exploitation, combined with the results of field geological survey and field drilling construction, the development and utilization of groundwater in gongyi city, Henan Province is divided into four areas: intensified exploitation, controlled exploitation, reduced exploitation and planning and utilization difficulties, which provides a theoretical basis for the rational development and utilization of regional groundwater.

(5) Summarized the technical methods of groundwater exploration and the experience of finding water in Gongyi, Henan.

In the process of finding water and drilling wells for emergency drought relief, technologies and methods such as high-density electrical method, induction electrical sounding and logging are applied. According to the characteristics of this area, "one-time experience of high-density electrical prospecting", "two methods of well determination" and "four drilling methods" are summarized.

Experience of a high-density electrical exploration: in Gongyi area, the experience of this method is to find low resistance in the high resistance of bedrock mountain area and high resistance in the low resistance of loose layer.

There are two methods to determine the well: one is to determine the well by analyzing the geological structure and regional hydrogeological conditions; Secondly, the well is determined by combining high-density electrical method and electrical sounding technology with structural-hydrogeological conditions.

Four drilling methods: impact drilling; Rotary drilling; Excavator+rotary drilling rig+pneumatic DTH hammer combined drilling; Combined drilling of rotary drilling rig and pneumatic DTH hammer.

The above experience and methods are applied to emergency drought-resistant water well drilling in Gongyi area, and the drilling completion rate is 100%, and there is no dry well, so the drilling efficiency and effect are very remarkable.

(6) The database of groundwater exploration in the serious water shortage area of Huaihe River Basin (Gongyi, Henan) was established.

Second, the economic and social benefits

Groundwater exploration in gongyi city, Henan Province, which is seriously short of water, is a major project deployed by the Ministry of Land and Resources and organized and implemented by China Geological Survey to support drought-resistant water exploration in Henan Province, which reflects the great concern and help of the Party and the government to people in water-deficient areas. The implementation of the "exploration-production combination" well project will solve the problems of drinking water for people and livestock and farmland irrigation in the working area to a great extent. The results of the project can provide rich geological information for the development of social and economic integration in gongyi city, and provide scientific basis for the rational development and protection of groundwater resources in this area. The project puts forward measures and suggestions for rational development and utilization of groundwater resources and ecological geological environment protection, which can ensure the demand of local people's life and agricultural production for water resources. The application of the project results will solve the long-term serious water shortage problem in this area, and have a lasting impact on the rational utilization and protection of groundwater resources, especially on ensuring water supply demand and social and economic sustainable development.

After the completion of this emergency drought relief work, in order to make the drought relief emergency demonstration project play a long-term benefit as soon as possible, gongyi city Land and Resources Bureau and Water Affairs Bureau jointly organized an investigation of supporting facilities (transformers, pump houses, line works, etc.). ) the required funds, timely preparation of the required funds budget and report to the gongyi city municipal government. Gongyi city municipal government soon allocated nearly 2 million yuan for the construction of supporting facilities.

After learning that our center's drought-resistant well-drilling commando team will return to Nanjing on April 29th, many villagers in gongyi city have taken the following measures: "Don't forget to drill wells when drinking water, and always feel that Nanjing has a variety of customs", "Drilling wells to support agriculture and care for the people", "Drilling wells for the people and benefiting the people" and "fighting drought".