What are the sand dunes commonly found in the Indian Desert called?

Question

Question

This question was previously asked in

RRB JE CBT 2 (Mechanical Engineering) ReExam Official Paper (Held On: 04 Jun, 2025)

Answer 1

The Correct answer is Barchans.

Key Points

Barchans are crescent-shaped sand dunes commonly found in desert regions, including the Indian Desert (Thar Desert).
They are formed by the action of wind, which transports sand grains and deposits them in areas where the wind velocity decreases.
Their characteristic crescent shape is formed due to wind blowing predominantly from one direction.
The tips or "horns" of the barchans face the direction in which the wind is blowing, while the steep slope is on the leeward side.
Barchans are commonly found in areas with limited vegetation and an abundant supply of loose sand.
The Thar Desert, located in the northwestern part of India, is an example of a region where barchans are prominently observed.
These dunes are important features of desert landscapes and are studied for understanding the process of aeolian sediment transport.

Additional Information

Loess
- Loess refers to fine-grained, wind-deposited sediment, primarily composed of silt.
- It is often found in regions like China, Central Europe, and the Mississippi Valley of the United States.
- Loess is known for its fertility and is widely used for agriculture.
- Unlike barchans, loess deposits are not shaped into dunes but form extensive blankets of sediment.
Moraines
- Moraines are landforms composed of debris deposited by glaciers.
- They are found in regions with glaciers, such as the Himalayas, Alps, and Rockies.
- Moraines can be classified into types such as lateral, terminal, medial, and ground moraines.
- These features are typically associated with glaciated landscapes rather than deserts.
Cirques
- A cirque is a bowl-shaped depression formed by the erosive action of glaciers.
- They are common in mountainous regions like the Himalayas, Andes, and Alps.
- Cirques are often the starting points of glaciers and are not related to desert environments.
- They typically lead to the formation of lakes known as tarns once the glaciers retreat.