Groundwater is not directly exposed like rivers, lakes, and the sea, but is hidden below the surface, which we usually do not see. Below the ground is soil and rocks. Where is groundwater? In fact, most of the groundwater is stored in the pores of soil and rocks, and a small part exists in the form of underground rivers and underground lakes in naturally formed underground caves.
We poured water on the mud, and the water would quickly seep into the ground, leaving only a few traces on the surface. This is because the soil is composed of loose grains. The grains can absorb moisture, and the grains can also store moisture. The rock texture is hard, but there are also voids inside, which provides storage space for groundwater. In fact, there are absolutely no water-bearing rock formations in nature.
Scientists divide underground rock formations into aquifers and aquifers. The aquifer and the aquifer are complementary. We can think of the aquifer as a plate, and the aquifer above the plate is a sponge filled with water. If the plate is gone, the water in the sponge will leak down due to gravity, so the preservation of groundwater by aquifers and aquifers is very important.
Groundwater is rarely polluted, so people in many areas use groundwater for domestic water. So where is the source of groundwater? In general, groundwater is just like a surface river, and the source of water comes from the atmospheric precipitation in the sky-rain and snow. This water seeps into the ground from the surface and is stored in rock formations when conditions are right.
Groundwater is an important component of the earth's water cycle. Although the groundwater is hidden underground, we usually cannot see it, but it maintains the health and stability of the earth's water circulation system.