Mountain formation
Mountain formation is the set of geological processes that build elevated terrain, including crustal deformation, volcanic construction, and uplift.
Orogeny: The set of geological processes that form mountain belts through deformation, magmatism, and crustal thickening. This broader process groups the tectonic changes that build many mountain ranges.
Lithosphere: Earth’s rigid outer shell, comprising the crust and the uppermost mantle. Mountain-building deformation acts on this shell and its moving plates.
Himalayas: A mountain range in Asia formed by the ongoing collision of the Indian and Eurasian plates. The Himalayas exemplify continent-to-continent collision and continuing crustal shortening.
Weathering: The breakdown or alteration of rock at or near Earth’s surface by physical, chemical, or biological processes. Weathering wears down the rocks that uplift and volcanism add or expose.
Plate tectonics: The theory that Earth’s lithosphere is divided into moving plates whose interactions shape the planet’s surface. Plate motion supplies the collisions and subduction that drive many episodes of mountain building.
Continental crust: The relatively thick, low-density part of Earth’s crust that underlies continents. Its buoyancy and thickness influence how collision raises mountain belts.
Andes: A mountain range along western South America associated with subduction of the Nazca Plate beneath the South American Plate. The Andes show how oceanic subduction can combine uplift with volcanism.
Erosion: The removal and transport of rock and sediment by water, wind, ice, or gravity. Erosion lowers mountains and redistributes the material their formation raises.
Crustal thickening: An increase in the thickness of Earth’s crust, commonly caused by tectonic shortening or magmatic addition. Thickened crust can rise buoyantly and sustain high mountain belts.
Convergent boundary: A plate boundary where two tectonic plates move toward one another. Convergence produces the compression and subduction associated with major mountain ranges.