Mountain Formations

What are Mountains?

Mountains are land forms that rise above the surrounding terrain. They are made of rocks and earth. Mountains appear to be rocky and barren, they also excel in height. Mountains form in various ways. Three of these ways include: Fold, Block, and Volcanic.

What are Fold Mountains?

A fold mountain is the most common type of mountain. The largest mountain ranges in the world are fold mountains. Fold mountain formations take place over a large period of time. Fold mountains are formed when two plates collide. This causes their edges to crumble, similar to the way paper folds when pulled together.

Himalaya Mountains

Some of the most famous fold mountains is located in Asia. They're called the Himalayas. For thousands of years, these mountains have proven to be significant to the people of South Asia. It influences their literature, mythologies, and religion. Its name derives from the stems, "hima" and "alaya". Hima means snow, and alaya means abode.

These mountains form the northern border of the indian subcontinent. This is a nearly impassable barrier between it and the lands to the north. These ranges are part of vast mountain belts that strech halfway around the world from North Africa, to the Pacific coast of Southeast Asia. The mountains themselves stretch for about 1,500 miles from west to east. It's between Nanga Parbat, in the Kashmir region and Namjagbarwa, in the Tibet Autonomous Region of China. These mountains are bordered to the northwest by the mountain ranges of Hindu Kush, and the Karakoram. To the north of this is the Plateau of Tibet. From the south to the north of the Himalayas vary between 125 and 250 miles. The entire area covers around 230,000 square miles.

What are Block Mountains?

Block mountains are formed when faults or cracks in the earth's crust force some materials or blocks of rock up and others down. Instead of the earth folding, the crust fractures, or pulls apart. It then breaks up into blocks or chunks. Sometimes the blocks of rock move up and down. This happens as they move apart, and blocks of road end up being stacked upon one another. The higher blocks are called horsts and troughs are called grabens.

Sierra Nevada Range

The Sierra Nevada Range is a famous example of block mountains. This mountain range is located in western North America. It runs along the eastern edge of California. This mass lies between the Central Valley depression to the west, and the Basin and Range Province to the east. It extends more than 250 miles northward from Mojave Desert, to the Cascade Range of northern California and Oregon. This range varies from 80 miles wide at Lake Tahoe, to about 50 miles wide in the south. The peaks range from 11,000 to 14,000 feet above sea level. Much of the rock in this area consists of granite or a relative of granite.

What are Volcanic Mountains?

Volcanic mountains start off as a simple crack in the Earth known as a volcanic vent. Magma erupts out of the ground as lava flows, clouds of ash, and explosions of rock. Keep in mind that magma is the liquid inside the volcano before it comes to the surface and lava is the liquid outside of the volcano as it flows. This material then falls back to Earth around the vent and complies around it. This process takes place over a long period of time.

There are different types of volcanic mountains such as: Cinder Cone, Shield, and composite. Cinder cone mountains are made up of material blasted out of the volcano then rains back down. These volcanoes aren't expected to be large. Shield volcanoes are built up by many lava flows. This lava can flow over a large distance causing it to be immense in width. A composite volcano is made up of many layers of ash, rock, and hardened lava. Some of the most famous volcanoes in the world fit into this category.

There isn't just volcanic mountains on Earth. The largest mountain in the entire Solar System is Olympus Mons, which is located on Mars. This is a shield volcano that has grown to be more than 21 km tall.

Mount Vesuvius

Mount Vesuvius is a famous volcanic mountain located on the west coast of Italy. This volcano is infamous for the eruption in A.D. 79 that completely buried and destroyed the city of Pompeii and Herculaneum. It is estimated that 13,000 people died all together from this eruption.

By: Marissa Spencer