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continental collision

orogenic beltsforeland basins

ssss1 (a) Ocean basin shrinks by subduction, as continents on two plates converge. (b) Continental collision produces a larger continent from two continents joined by a suture zone. Horizontal shortening and vertical thickening are accommodated by folds and thrust faults in the resulting orogenic belt.

A striking example of a modern orogenic belt is the Himalayan Mountain range formed by the collision of India with Eurasia over the past 40 Ma. The continued convergence of the Indian micro‐continent with Asia has resulted in shortening and regional uplift of the Himalayan Mountain Belt along a series of major thrust faults and produced the Tibetan Plateau. Limestones near the summit of Mt. Everest, Earth's highest mountain, were formed on the floor of the Tethys Ocean that once separated India and Asia. They were then thrust to an elevation of nearly 9 km as that ocean was closed and the Himalayan Mountain Belt formed by continental collision. The collision has produced tectonic indentation of Asia, resulting in mountain ranges that wrap around India (ssss1). The Ganges River in northern India flows approximately west‐east in a trough that represents a modern foreland basin.