How Are Mountains Formed?
Fold mountains are the most common type of mountain, and these types of mountains make up the longest mountain chains in the world. Fold mountains are formed when two continental plates collide into one another. The edges of the plates crumble, and are pushed upwards. Examples of Fold Mountains are: The Himalayn, the Alps, the Andes, the Rockies, and the Ural mountains.
Fault-Block mountains are created when faults and cracks in the Earth's crust push materials and blocks of rock up and down. The Earth's crust breaks apart, and the rocks are broken into different chunks. These chunks can get stacked together. Often, fault-block mountains are incredibly steep front side, with a sloping back side. Examples include: The Sierra Nevada mountains, and the Harz Mountains.
Sierra Nevada Mountains
Volcanic mountains are, as one would assume, made my volcanoes. Volcanoes erupt magma from the magma chamber. When this magma (called lava once on the Earth's surface) is erupted, it has to fall back down somewhere. When it does, the combination of ash and lava cool, forming rock. After millions of years, enough lava will have been cooled to form mountains! This is pretty interesting! Examples include: Mount St. Helens, Mount Pinatubo, Mount Kea, and Mount Loa.
The Eruption of Mount St. Helens