Topographies Formed By Underground Water

In the earlier articles, we have learned that due to endogenous forces, differences are created on the land, while the process of leveling of land is done by exogenous forces. Along with this, we also learned that what types of land forms are formed by the flowing water i.e. river. Continuing in this sequence, how are the topographies formed by underground water in this article? We will try to know this.

Topographies Formed By Underground Water

Underground water i.e. water located under rocks in the ground. It is found up to a maximum depth of 6 miles. Due to the amount of pressure at a greater depth than this, the pores and cracks of the rocks are closed. Some important points related to ground water are as follows –

• Spring: When underground water naturally flows out from the ground floor, it is called spring. It is mainly found in hilly areas.
• Artesian Wells: Such a well, from which water keeps coming out of the surface automatically, is called artesian well. The world’s largest artesian basin is located in Australia.
• Ground Water Level or Water Table: The level below which permeable rocks remain saturated with water is called ground water or water table.
• Carst Topographies: The landforms formed by underground water are called Carst topographies. It may have been named after the topography of the limestone region of the Adriatic coast of Yugoslavia. The work of erosion and deposition is also done by underground water, due to which different types of topography are formed. Whose names are as follows –
  1. Terra – Rossa
  2. Lapies
  3. Sink Hole
  4. Caverns or Cave
  5. Blind Vally

also read : पवन निर्मित स्थलाकृतियाँ ( Landforms Made by Wind )

1. Terra – Rossa

When some parts of soluble rocks dissolve and enter into the ground by the dissolving action of rainwater, a thin layer of soil is formed on top of the surface, which is called terra-rosa. Clay, lime and iron predominate in this layer.

2. Lapies or Clint or Karren or Bogaj

As a result of dissolution, the upper surface becomes very rough, uneven and with thin ridges, which are called lapies. It is called Lapies in France, Klint in England, Keren in Germany and Bogaz in Siberia.

3. Sink Hole

Due to the dissolving action of rain water, many types of small pores develop at the joints of rocks, which are called solution pores. Their depth can be up to 10 meters. Their shape is cylindrical or cylindrical. They are given different names on the basis of size and nature.

• Solution Pore: Funnel or cylindrical and deep and dry solution pores are called solution pore.
• Doline: The wide sized slurry pore are called dolines. It is made up of many solution pore. Their depth is 2 – 15 meters and diameter is up to 10 – 125 meters.
  • Karst Lake: When the lower hole of the doline is closed by the clay, the water does not seep down to the ground. As a result water gets stored in it. Thus a temporary lake is formed. Which is called karst lake.
  • Karst Window: When the ground between two adjacent dolines or solution pore located in the course of underground rivers collapses, underground water flows become visible on the surface. The topography thus formed is called karst window.
• Yuvala: When several dolines join together to assume a large size, it is called Yuvala. Their diameter is up to 1 km.
• Polie or Polje Yuvala: The slurry pore larger than Yuvala are called Polie or Polje Yuvala. The ‘Livno’ polje located in the Balkan region is the world’s largest polje. Their bottom is flat and the walls are erect.

4. Caverns or Cave

When a cave-like topography is formed under the ground as a result of erosion and dissolution of underground water, it is called a cave. Underground water flows continuously through this cave.

• Stalactite: Due to the dripping of water in the caves, the deposits of lime hang from the roof of the cave, which is called stalactite.
• Stalagmite: Stalagmite is a column made of selected columns on the floor of the cave.
  • Cave Pillars are formed when stalactite and stalagmite mix together.

5. Blind Vally

In karst regions, the water solution of rivers starts seeping down through the solution pores, due to which the river valley beyond it remains dry. Hence it is called dry river valley or dry river bed. Whereas behind this the solution pores from which the rivers form a valley, it is called blind valley.