The electric exploration method is divided into artificial electric field method and natural electric field method. Artificial electric fields also include professional methods such as DC power supply, induced current, and controllable sources. These methods are mostly used in various large geological census projects, involving thousands of measurement lines and measurement points, but they are quite inconvenient to use, especially handling power supply The device often requires a lot of labor. After decades of development, the natural electric field method has overcome the unfavorable factors such as signal interference and depth error, and has obtained exploration with traditional electric methods.
Under the same geological conditions, it is important to make the well formation technology scientific and reasonable in order to maximize the water output of the well, minimize the drawdown, provide the best water quality and have the longest service life.
1. The water filter pipe should face the aquifer. Once the two are misaligned, the inlet resistance is much greater, increasing the depth. For this reason, a physical detection well must be carried out before the down pipe is run to accurately determine the location of the aquifer.
2. The opening rate of the water filter pipe should be sufficient. No matter what the pipe opening rate should not be less than 10%. Most of the cement pipes produced by the local method are only 1-2%, and the resistance to water inflow is very large, which is not allowed.
3. There must be ribs between the water filter pipe and the filter screen. If there is no ribs, the filter mesh is closely attached to the well pipe, and only the mesh facing the water inlet hole can enter the water, which is very easy to cause blockage and seriously affect the water output and service life of the well.
4. The mesh size and size of the gravel should be compatible with the aquifer. Otherwise, it is either water blocking or muddy water caused by the well.
5. For drilling with mud, the wall must be broken and replaced before going down the pipe.
At present, there are serious problems in the society of arbitrarily configuring the water filter tube, the water filter tube opening rate is too low, no reinforcement is added, the filter screen and gravel are unqualified, and the wall replacement and slurry replacement are not thorough. Most recharge wells of ground source heat pumps are not well recharged, which is an important reason. Our professional drilling team of the Groundwater Research Institute has formulated a set of drilling construction regulations for the above problems. Whether it is positive circulation or reverse circulation drilling, the results are very good.