Week 5 - The Andes Mountain Range

The Andes in South America have always been of great interest to me because of their variety of terrain. While exploring the Andes we saw lakes and grasslands, deserts and forests and volcanoes and glaciers. This is one of the largest mountain ranges in the world. It begins in Venezuela, where we began our adventure, and runs through six countries including Peru and Chile. It took weeks and many forms of transportation to explore them and we only scraped the surface.

  

Picture compliments of: http://www.broadheath.coventry.sch.uk/2white-life-in-the-andes-mountains/

The sheer size of the mountains is impressive and lead us to find information out on how they were formed. Our guide explained to us that an oceanic plate/crust (Pacific) moved under a continental plate/crust (South American/Nazca) during substantial tectonic activity many millions of years ago. He went on to explain a theory about the mountains being created when a large amount of rock was displaced by the over thickening of the areas crust. The movement of this amount of rock, caused a massive uplift in the remaining crust. The debate in this theory is not if it happened, but instead the timing of when it happened. The question at hand is if the Andes are older than originally thought. We were amazed that scientists were able to determine facts that happened 50+ millions of years ago.

This diagram was helpful in understanding his explanation.

Diagram credit: https://sciencestruck.com/formation-of-andes-mountain-range 

Compression stress is known to have created the Andes as it squeezed the rock inward, pushing them together and up. The Andes are considered fold mountains, caused when the South American and Pacific plates collided. The largest mountain ranges in the world are all considered fold mountains. "The Atacama fault is a strike-slip fault where two blocks move horizontally, along a vertical fault line." (Patil, 2018). As explained to us, his is the type of fault found in the Andes.

Picture compliments of: https://sciencestruck.com/formation-of-andes-mountain-range

We enjoyed learning many interesting facts that I had not known before. First, the majority of this mountain range is volcanic. While some of the volcanoes are in remote areas, we were able to travel to Cotopaxi just outside of Quito, the capital of Ecuador. This volcano presents the most threat of eruption and is also where we saw massive glaciers. Next we learned that some of the mountains remain underwater with only their peaks breaking the water line. These islands are known as Aruba, Curacao and Bonaire. Lastly we learned that the Andes are the source of the Amazon river. 

The Andes are so impressive and have so much to teach us. This was an amazing trip we will never forget.

References

https://www.sciencedaily.com/releases/2015/11/151118131817.htm

https://www.chimuadventures.com/blog/2017/03/andes-mountains-facts/

Patil, R. (2018). A Brief Explanation of the Formation of the Andes Mountain Range. Retrieved from: https://sciencestruck.com/formation-of-andes-mountain-range