What technical knowledge is needed to drill a well to find water

Well is a minimum water conservancy project since ancient times, however, it is a special water conservancy project involving multiple disciplines. Its characteristics, one is the universality of use. Whether it is a large amount of farmland irrigation, or a large number of small and medium-sized enterprises, most of them rely on wells to provide water, almost no well is not unrelated to the units and individuals; second is the hidden nature of the project. How the quality of the well is difficult to detect, once the quality of the problem can not be remedied; third is the high risk of investment. Drilling a dry eye is a large number of things, if not scientific, blindly drilling wells, most places fail more than success. Once there is no water, thousands of dollars to tens of thousands of dollars of investment will have been wasted. In this sense, the well is one of the highest risk, the most failed water conservancy projects; fourth is the complexity of technology. Generally believe that drilling a well is "drill a hole, down a tube", seemingly simple, the actual technical content is very high, involving hydrogeology, physical prospecting to find water, well technology, pump selection and other aspects of knowledge, is often not paid attention to, it is easy to fail more, poor quality, high risk problems. Although the learning of drilling wells to find water is very deep, but if the person has some scientific knowledge to reduce blindness, or a great benefit.

A. To study in detail the local hydrogeological conditions. If you do not understand the hydrogeology, do not study the hydrogeological conditions, but only believe in the instrumentation, measured points everywhere, can only be called "blind test". The following three aspects can be investigated and studied.

1. Study the topography and geomorphology. Topographic and geomorphological conditions determine the groundwater recharge runoff drainage conditions, control the weathering of the rock, affecting the groundwater abundance changes. To build reservoirs to have a watershed area, drilling wells also need to have recharge area, the same reason. If the lithological conditions are the same, low-lying terrain or terrain conducive to water catchment is more likely to become a well. However, some small plains and depressions are often dominated by muddy rocks underneath, which can easily be weathered and denuded to form lowlands where groundwater is not good.

2. Study the water-richness of rocks. Rocks can be divided into igneous rocks, metamorphic rocks, sedimentary rocks according to the genesis of the three categories, and then subdivided very complex. Regardless of the genesis, when hit with a hammer, the feeling of some hair "burgundy" (rigid), some hair "sheep" (flexible), some hair "brittle" (brittle), brittle rocks and limestone, etc. Soluble rocks are more likely to form wells.

3. Study the fracture development of rocks. Fractures are more developed near the fracture zone. Inclined rocks are easier to develop fractures than horizontal rocks.

B. To choose the suitable local geological conditions of the physical prospecting water search method

At present, the main method of physical prospecting to find water is electrical exploration. Electrical prospecting methods are divided into artificial electric field method and since (natural) natural electric field method. There are many specific methods, commonly used are duplex electric survey method, high-density electric survey method, vertical electric sounding, four-pole symmetric profile method, joint profile method, excitation polarization method, etc., each method has its own applicable conditions and interference factors, must be selected according to local conditions. After years of water search research by our institute, the more interfering factors in poor water areas, the more we use our independent invention of pqwt automatic ground water detector to distinguish the aquifer is very strong oh.