Ground water refers to the body of water derived from percolation and contained in the soil, subsoil and underlying rocks above an impermeable layer. This water originates from;
- When it rains, part of the rainwater runs off to form or join streams and finally into the oceans and lakes. The remaining percolates down into the ground.
- After winters, especially in the high latitudes, snow melts and part of this water runs off into oceans, lakes and seas but the remaining percolates into the ground.
- lakes\sea the lake or sea water may percolate into the earth to add on to the underground amount of water that already exists there.
- Magma-tic water. This is the platonic water that gets trapped in the rocks underground. It also adds to the amount that already exists there.
Surface water includes;
- Rain water falling directly.
- Run-off water.
- River water.
- Lake water.
- Sea water.
- Ocean water.
As water sinks into the ground , it forms underground water . the underground branch of water cycle process begins when water seeps through the soil and becomes a sub-surface water .this downward progress through the layers of the earth purifies water from impurities of surface water like mud and bacteria and adds to it calcium and iron compounds. The underground water saturates the ground up to the level of water table. Such water infiltrates into the ground in two ways;
- Through permeable rocks
- Through joints and faults.
Factors which affects the occurrence of underground water.
- Precipitation and evaporation in the area
- Porosity of the rocks
- Permeability of the rocks
- Vegetation cover.
Importance of underground water.
- Underground water provides sites for settlement.
- Water from the wells is used for irrigation in the dry areas.
- Springs form major sources of water for both domestic and industrial use.
- Springs form sources of various rivers.
- In areas which are under volcanic influence, the underground water is heated by hot magma to form hot springs or geysers.
- Hot springs also deposit some minerals, especially the salt particles, which are useful to man.
- Underground streams helps in keeping lakes fresh.
On my next research i will be looking on how the occurrence of underground water affects the surface.