Mountain belts on Earth are most commonly formed by collision of one or more tectonic plates. The process of collision, uplift, and subsequent erosion of long mountain belts often produces profound global effects, including changes in regional and global climates, as well as the formation of important economic resources, including oil and gas reservoirs and ore deposits. Understanding the formation of mountain belts is thus a very important element of earth science research.

Source: Curvy mountain belts