Drilling a well to find water is a highly technical and carefully considered task. In order to ensure the quality of the well and the amount of water produced, attention must be paid to the following aspects.
I. Study the local hydrogeological conditions
Before deciding where to drill a well, it is first necessary to conduct an exhaustive study of the local hydrogeological conditions. This involves the topography, the water-richness of rocks and the development of fissures and other aspects.
1. Topography and geomorphology: Topography and geomorphology determine the flow path of groundwater and the source of recharge. Low-lying areas or terrain favorable to water catchment are often more likely to become water-rich areas. However, it is also important to be wary of lowlands that may be composed of muddy rocks that are easily weathered and eroded, resulting in poor groundwater quality.
2. Water-richness of rocks: Different types of rocks have different water-richness. Igneous, metamorphic and sedimentary rocks differ in their water-richness. In addition, the brittleness, rigidity and flexibility of a rock affects its potential for well formation. Generally, brittle rocks and soluble rocks such as limestone are more likely to form water-rich wells.
3. Fissure development of rocks: Fissures in rocks are the main channels for groundwater flow. Therefore, areas with well-developed fissures are more likely to become water-rich areas. Fault fracture zones and tilted rock areas are the focus of finding areas with well-developed fissures.
Second, choose the suitable method of physical exploration to find water.
At present, the main method of physical search for water is underground water detection electric exploration. Electric exploration method is divided into artificial electric field method and self (natural) natural electric field method. Specific methods are many, commonly used duplex electrical survey method, high-density electrical survey method, vertical electrical bathymetry, quadrupole symmetric profile method, joint profile method, excitation polarization method, etc., each kind of underground water detection has its own applicable conditions and disturbing factors, and must be selected according to local conditions. After many years of water searching research in our institute, the more in the poor water area, the more disturbing factors, the use of our independent invention of underground water detection, water resources exploration, and then carry out water search, you can greatly save resources. Especially the professional well drilling team can be equipped with this instrument.
C. Adopting scientific and reasonable well formation technology
Even under the same geological conditions, different well formation techniques can lead to huge differences in water output, water quality and service life of the wells. In order to ensure the quality and benefit of the well, it is necessary to adopt scientific and reasonable well formation technology.
1. Accurately determine the location of the aquifer: before lowering the pipe, the location of the aquifer should be accurately determined by using the physical exploration logging technology to ensure that the water filter pipe is directly facing the aquifer, so as to reduce the resistance of water intake.
2. Ensure the open rate of the water filtering pipe: no matter what kind of pipe is used, the open rate of the water filtering pipe should not be less than 10%, so as to ensure sufficient water intake area.
3. Use of padding: adding padding between the water filter pipe and the filter screen can prevent the screen from clinging to the well pipe, ensure that more mesh can enter the water, and reduce the possibility of clogging.
4. Choosing the right screen and gravel filler: The mesh of the screen and the size of the gravel filler should be compatible with the aquifer, in order to prevent blocking or muddy water from silting up the well.
5. Breaking the wall for slurry: If mud drilling is used, the wall should be broken for slurry before the pipe is lowered to remove the mud and impurities in the well to ensure the quality of water from the well.
To summarize, drilling wells to find water not only need to have in-depth understanding of the local hydrogeological conditions and research, but also need to choose the appropriate physical exploration methods and scientific and reasonable well formation process. Only in this way can we ensure the quality and benefit of the well and meet people's demand for water.
