Fold and thrust belts are formed when large sections of the Earth's crust are shortened and thickened by horizontal compression. This compression causes the rocks in the crust to fold and break, and the resulting thrust faults can create mountain ranges.

The Himalayas are a classic example of a fold and thrust belt. They were formed by the collision of the Indian Plate with the Eurasian Plate, and the resulting compression has created some of the highest mountains in the world. Other examples of fold and thrust belts include the Alps in Europe, the Appalachians in North America, and the Andes in South America.

Fold and thrust belts are important geological features because they can provide information about the history of a region and the forces that have shaped it. They can also be important economic resources, as they often contain valuable minerals and oil and gas reserves.