[Geography Notes] on Karst Pdf for Exam

The terrain is usually characterized by barren grounds, caves, sinkholes, underground rivers, and the absence of river lakes, ponds, and streams in karst geology. In karst geology, the excavating effects of underground water or massive soluble limestone surround the terrain. The northeast area of the Gulf of Trieste in Slovenia is covered with limestones. If the cave becomes large enough on the surface, the top portion collapses. This is called a sinkhole. The water flowing through the cakes widen it and it forms caves. In north China, the pipes are 2m in diameters and run roughly parallel to the ground level. In China “loess karst” is characterized by young loess, though not entirely under it.

Doline Geology

A surface that is closed and forms a depression in the form of solution doline and sediment covered with carbonate rock is a subsidence doline geology. After evacuating the sediment-covered karst into an underneath doline an evacuation was developed. The result of the surface is either rapid or slow. The subsidence doline according to the type of subsidence is of two types. They are dropout doline and suffosin doline. The result of cohesive sediments is catastrophic due to sudden subsidence. This is known as dropout subsidence. In the case of soil, the clayey portion moves slowly into the cavity section and the thick fragments remain on the surface. These are known as suffosin doline geology. 

Condition for Karst Geology

1. The rocks are relatively thick and massive in size. Eg: limestone, dolomite, and chalk.

2. Very close to the ground surface carbonate rocks are found.

3. Limestone rocks should not be porous.

4. The structure of limestone should be folded, fractured, and highly cracked.

5. To form a clay solution moderate to heavy rainfall should happen.

6. Water must circulate in the soil to form karst geology that is a considerable relief.

Many rare animals like bats, cave living invertebrates, plant species grow on the surface during spring and seeps. Fish, snails, and mussels depend on the Karst spring lakes, rivers, and ponds.

Topology

A set that is covered with a structure is called a topology which allows continuous deformation in the subspaces and all continuity. Some examples of topology space are Euclidean spaces and metric spaces. Any kind of distance or metric defines topology deformations, breaking, twisting, and stretching of objects are included in the study of doline geology. Tearing is not followed in topology. Topology is the study of curves, surfaces, and other objects in the plane and three-dimensional space. Someone who cannot distinguish between a coffee cup and a doughnut is called a topologist. 

Geology

Geologists study some of the most important problems that our society is facing. Some problems that occur in energy generation, water supply, mineral resources, and natural hazards like earthquakes, volcanic eruptions, landslides, and floods. We must take care of our geology and stop pollution as much as possible. 

Questions and Answers

1. In Which Chemical Limestone can be Dissolved?

Ans: Carbonic acid is a chemical that can dissolve limestone. By mixing CO₂ and water(H₂O) we form aqueous CO₂ which in turn mixes with water to make carbonic acid. The carbonic acid then dissolves to form calcite, limestone, and CaCO₃. 

2. In Non-Karst Areas Drainage Basins are found on Land?

Ans: Water from precipitation becomes first-order tributaries, second-order streams, lakes, and flows into the mainstream. Due to dynamic evolution and subterranean nature, the karst drainage is characterized. At surface drainage, the underground karst is developed. Until surface rock is exposed rivers must be cut down. At that point, the solution must dissolve by the limestone and tributary water may vanish into the ground like a sinking stream or shallow hole.

3. What is Karst Hydrology?

Ans: All rocks are porous and can retain water through their pores and transmit water through their spaces. When a rock can store large quantities of water, it is called aquifers. The water percolates on the surface until it reaches the phreatic zone in the aquifers. Below the vadose zone, the phreatic zone is present and they are separated by a layer of the water table. 

There is a distinction between groundwater and surface water in non-karst areas. According to topography surface water is loosely drained into the lakes and ponds.  Aquifers are independent of surface drainage boundaries.

4. Impacts of Karst due to Humans?

Ans: With rapid surface water entry and all connectivity and mixing it is easy to find the reason for groundwater contamination. But the degradation of the Karst system is not only due to the groundwater, there are many more reasons:

1. Occupation of cave areas.

2. Cutting down plants.

3. agriculture.

4. Exploitation of water and its wastage.

5. Exploitation of minerals.

6. Tourism planning and reconstruction of concrete.

7. Explosive activities and fights in the borders.