KARST EROSION: PROCESSES, TYPES AND EXAMPLES - ENVIRONMENT - 2025

The karstic erosion is one of the types of erosion that can be found in the environment. This natural process occurs thanks to the action of a stream of water that has certain levels of acidity.

The circulation of water on the surface of a limestone rock causes that, with the prolonged passage of time, modifications are generated on the structure. This type of process can occur both on the earth's surface and in the subsoil.

Karst zone in El Torcal, Antequera (Spain). RaMaOrLi, via Wikimedia Commons

There are different types of karst erosions, which leads directly to the type of shapes that can be generated on the surface of the rock on which the body of water circulates.

Two examples of this type of natural phenomenon are the Torcal de Antequera, located in Spain, and the Grutas de Cacahuamilpa National Park, located in Mexico.

Karst processes

By acidification of the water

The karstification process occurs when a source of water, which contains a certain level of acidity, indirectly causes the dissolution of calcium carbon found in limestone rocks.

Acidification of water occurs when, thanks to direct contact with other surfaces, it obtains a greater amount of carbon dioxide.

The need for acidic water to be present to dissolve a rock varies depending on the type of stone. An example of this are evaporites, which do not require this type of liquid to experience a change in their shape.

By the evaporation of water

Another way in which the shapes of rocks can vary thanks to the action of water is through evaporation.

A body of water that contains gas and calcium bicarbonate is capable of reaching a cavity larger than the cracks it previously passed through. Once in place, the liquid can undergo a slow evaporation that causes the dissolved salts in it to crystallize due to certain circumstances.

The action of water can cause a drip inside a cave, allowing the formation of stalactites on the ceiling and stalagmites on the floor: columns that can form geodes when joined.

Types of karst erosion

-Exokarst erosion

Karst erosion occurs on the earth's surface. This type of geological formation is divided into several subtypes: lapiaces, poljes, sinkholes and canyons.

Lapiaces or lenares

Lapiaz in Riotuerto (Cantabria). Emilio Gómez Fernández - Corso, via Wikimedia Commons

This type of erosion has definite characteristics: the influence of water on the rocks produces the formation of grooves or cavities that are separated by thin partitions.

Lapiaces tend to appear outdoors, specifically in limestone or gypsum outcrops, which are affected by karst erosion when water overflows over slopes or on flat surfaces that have cracks.

Poljés

Poljé de Vega de Comeya, in Asturias. Pelayo Alonso Huerta, from Wikimedia Commons

It is a valley that is large and has irregular contours, surrounded by steep edges in which are limestone rock formations. This depression occurs in a large karst rock massif.

Poljes are formed by the dissolution of limestone blocks and a slight flow of water can commonly be observed disappearing through an opening in the ground. For this reason, in some occasions the excess of this liquid can cause the flooding of the space, which gives rise to a lake.

Torcas

Torcas de los Palancares, Cuenca. Miguelno, from Wikimedia Commons

Also known as sinkholes, this type of formation is characterized by occurring in those places where a body of water stagnates. They are usually generated on surfaces that have a limestone rock formation and clay in different proportions.

The torques can have a variety of shapes and, in some cases, can be joined together by the action of karst erosion.

Canyon

Grand Canyon, Arizona. Morn the Gorn, from Wikimedia Commons

This type of geological formation occurs when the current of a river causes the erosion of land, which gives rise to a deep crevice that has almost vertical walls.

The canyons, also known as gorges, can be generated by the action of a river current and a karstification process.

-Endokarstic erosion

Endokarstic erosion occurs inside the earth's surface. Two of the geological formations of this type that exist are sinkholes and chasms.

Sinks

Sinkhole in Dolenje Ponikve, Slovenia. Slovene Wikipedia user MGlava7

Sinks form when a stream of slightly acidic water slowly erodes limestone soils and subsequently seeps into them. This process allows the formation of an underground cave over time.

At a certain point in the process, the accumulation of water on the surface causes the cave floor to collapse, which gives way to a kind of sink.

If more

Chasm. Ky MacPherson, from Wikimedia Commons

This type of geological formation is a cavity or cave that is formed by a process of karst erosion. It can also be generated by the collapse of the ceiling of a cavity, a space through which a stream of water can filter into the cave.

It is a cavity that has an opening in the surface through which a slight stream of water enters.

Examples of karst formations

Torcal de Antequera

El Torcal de Antequera is located in the province of Malaga, Spain. It is located in a geological formation in which the action of the water contributed to the limestone rocks taking an attractive shape for visitors.

El Torcal de Antequera is a protected natural area and is a place of great tourist interest. It is made up of limestone rocks of different types, which had their origin on the seabed millions of years ago, during the Jurassic period.

The sediments from the seabed were united and later lifted on the surface by the different movements of the tectonic layers. Over time, there were cracks in the structure and a series of failures. Erosion, for its part, gave it the characteristic appearance that it currently has.

Grutas de Cacahuamilpa National Park

With an important tourist attraction, this natural space is located in the state of Guerrero, Mexico. It is a protected natural area and is considered one of the most important caves in the world, as it is seen as a beautiful landscape.

References

1. Karst, National Geographic Portal, (nd). Taken from nationalgeographic.org
2. Living on Karst, Portal Virginia Department of Conservation and Recreation, (nd). Taken from dcr.virginia.gov
3. Karst, English Wikipedia Portal, (nd). Taken from en.wikipedia.org
4. Karst Erosion, Portal Academic, (nd). Taken from esacademic.com
5. Karst erosion, Portal Esquiú, 2010. Taken from elesquiu.com
6. The Karst Landforms and Cycle of Erosion, Portal Geography Notes, (nd). Taken geographynotes.com