Fold Mountains Notes

Fold Mountains

Fold mountains are formed when two plates collide.
The heavier plate (usually oceanic) sinks into the mantle.
The edge of the lighter plate (usually continental) crumples and the layers of rock fold upwards.

Long narrow ridges called anticlines are formed.
The valleys in between the ridges are called synclines.
The Andes Mountains in South America were formed when the Nazca Plate collided with the South American Plate.

Fold Mountains are found on the edge of continental plates (e.g., the Andes in South America) or at places that used to be the edge of continental plates (e.g., the Atlas Mountains in Morocco).

Formed 400 million years ago.
Eurasian Plate and American Plates collided.
These mountains have been worn away over time and usually have rounded peaks.
Examples:
- Dublin Mountains (Ireland)
- Wicklow Mountains (Ireland)
- Appalachian Mountains (North America)

Occurred when the Eurasian and African Plates collided about 250 million years ago.
These were once as high as the Alps but have worn down over time.
Examples:
- MacGillicuddy’s Reeks (Ireland)
- Galtee Comeragh (Ireland)
- Knockmealdown (Ireland)

The highest mountains in the world formed during this folding period.
About 30 to 35 million years ago - they are the youngest mountains in the world.
Examples:
- The Alps (Europe)
- The Andes (South America)
- The Rockies (North America)
- The Himalayas (Asia)

Farming:
- Upland areas are only suitable for pastoral farming (e.g., grazing sheep).
- If the slopes are too steep, a farmer may use upland for forestry, e.g., the Wicklow Mountains.
- The trees grown in this area are coniferous as these can survive colder temps.
Tourism:
- Upland areas offer tourist attractions, e.g., picnic + viewpoint sites.
- Hill walking = one of the top five tourist activities in Ireland.
- Tourists/visitors spend money on local services such as hotels + restaurants (this creates jobs).
Transport:
- It is more difficult to build in upland areas – slopes are too steep.
- It can be too expensive to drill tunnels through mountains for routeways.
- Major roads + railways often must go around mountains.
- Longer journeys add to the cost of transport and make mountain areas less attractive for the location industry.

Settlement + Population:
- Upland areas are windier, wetter, + colder than lowland areas – fewer people want to live in these conditions.
- These areas are difficult to farm, so settlement tends to occur in lowland areas.
- Mountains have few services such as schools + shops.
- This is a vicious circle.

*Earthquakes

The Himalayas were formed when the Indian Plate collided with the Eurasian Plate.
Earthquakes are a constant danger – in mountainous regions, there’s an added danger of landslides.
April 25, 2015: A 7.8 magnitude earthquake occurred in Nepal.
It killed ~8,000 people + injured more than 10,000.
Many villages were buried under avalanches + landslides.
Roads were damaged + 130,000 buildings and houses were destroyed.
This affected 8 million people.
Mountains are difficult to access – slowed down rescue efforts.
Tourism:
- Major industry in the Himalayas, especially at Mt. Everest.
- The Nepalese government requires climbers to purchase permits to climb mountains.
- This money + the money tourists spend while in the mountains is a valuable source of income for Nepal.
- Tourism = 5% of Nepal’s income + 1.5 million jobs are supported by this.
- Over 1 million tourists visit Nepal each year.
Agriculture:
- The majority of Nepal’s population (28 million people) lives in the south of the country, which has a narrow strip of lowland.
- 2/3 of the population depends on agriculture to make a living – crops such as tobacco, sugar cane + grains can be grown in the south.
- In the north, the lower slopes of the Himalayas can be used for grazing, but the land is less able to support many people.
- Hence, many people migrate to the capital city in Kathmandu and to the south of the country.