Sunday, December 2, 2012

How might Yellowstone look 1,000 and 100,000 years in the future?


Yellowstone National Park is a beautiful location that people can visit to enjoy the natural world. The natural landscape is constantly changing. Yellowstone is no exception to this. When trying to predict what this park might look like in the future, it is important to remember that Yellowstone is an active volcano.

The past volcanic activity has had a drastic effect on the current landscape of Yellowstone. Passed eruptions of the volcano underneath Yellowstone have created a large crater that most of the park lies in. According to Richard A. Lovett author of Yellowstone Eruptions more Numerous then Thought? “…a roughly 40-mile-wide crater formed by the collapse of a massive volcanic cone during the area’s most recent super- eruption some 640,000 years ago”(Yellowstone Eruptions more numerous then Thought?).

(Image shows the outlines of several calderas in the Yellowstone area. Image from Google Images).

When the magma chamber of a volcano empties in an eruption, the empty chamber can no longer support all the heavy material above it and collapses.
 
(Video shows how a caldera is formed using flour and a balloon to represent the crust of the Earth and a magma chamber. Video from Youtube.com)
 
As the video shows, the flour or crust of the Earth stretches as the caldera is formed. This stretching makes the crust thinner around the edges of the caldera, this means that the magma under the park is closer to the surface and can heat any water that is between the magma chamber and the crust. This is how geysers such as Old Faithful are created, as well as, hot springs, and mud pots.
(Image shows how a caldera is formed, and how the caldera leads to the formation of geysers, hot springs, and mud pots. Image from Google Images).


 (Video shows several different volcanic forms in Yellowstone. Video from Youtube.com)

Yellowstone 1,000 Years in the Future 

There have been dozens of articles and documentaries created in the last few years saying that the Yellowstone volcano may explode soon. While an eruption of a volcano is always possible, it is highly unlikely that Yellowstone will have a large eruption such as the one that formed the Yellowstone caldera. It is much more likely that Yellowstone will continue to have small eruptions; not the famed “super volcano eruptions” which are believed to have the power to plunge the entire earth into a volcanic winter. This is because according to Bob Christiansen in the article When Yellowstone Explodes by Joel Achenbach, the Yellowstone hotspot that is responsible for the volcano is now under the thicker crust that is at the base of the Rocky Mountains. This makes an eruption much less likely (When Yellowstone Explodes). A thousand years in the future it is much more likely that other geographic phenomenon will affect Yellowstone’s appearance, such as small earthquakes or small volcanic eruptions.
     The global climate change our planet is currently experiencing will have a drastic change on the landscape of Yellowstone. According to a Yellowstone Wiki article about vegetation, Yellowstone’s forests are primarily made up of Lodgepole pine trees, along with the Douglas-fir, Engelmann spruce, Subalpine fir, and Limber pine (Vegetation). All of the species of pine trees rely on the colder temperatures that occur from the higher elevations within the park. According to the Glacial Forms and Processes Lecture, there has been a pattern of pine trees migrating northward as the temperature of the planet increases (Glacial Forms and Processes Lecture). As our planet’s temperature continues to rise in the next thousand years, the large pine tree forests that cover the park will begin to migrate to colder areas, leaving the landscape open for new types of vegetation to live in the area once dominated by pine trees.



(Image shows pine forest near a geothermal feature in Yellowstone. Image from Google Images). 

Yellowstone 100,000 Years in the Future

       The landscape of Yellowstone is likely to experience a large volcanic eruption within the next hundred thousand years. The reason the eruption is more likely further into the future is because of plate tectonics. Currently the hot spot is under the thick crust of the Rocky Mountains, since the plates under the Earth’s crust are in a constant state of slow motion the hotspot will not stay under Wyoming.

(The map above shows the calderas made by the hot spot. By tracking the path of the calderas, it appears that the tectonic plate is roughly moving in a south west direction. Eventually, the hotspot will move out from under the thick crust of the Rocky Mountains; to an area where the crust is thinner.  Image from Google Images).

(Image shows a map of the Rocky Mountains with Yellowstone in the bottom right corner. Image from Google Images).
  

Once, the hotspot has moved from under the thicker crust,a large volcanic eruption is likely to occur. During the time the hotspot is under the crust of the Rockies the magma chamber is becoming larger, when it is no longer under the thicker crust; it will erupt, and the volume of magma release will be significant. Once the magma has been released, the empty chamber will collapse forming another caldera.
       The beautiful geothermal features, and the large pine forests that Yellowstone National Park is known for, are not permanent fixtures of the landscape. These two features will disappear in the next thousand to hundred thousand years, leaving a very different physical geography behind.


Sources
Achenbah, Joel. "When Yellowstone Explodes". National Geographic. August, 2009. http://ngm.nationalgeographic.com/2009/08/yellowstone/achenbach-text/1
 Caldera Demostration video from Youtube.com
Geothermal Features of Yellowstone video from Youtube.com
Glacial forms and Processes Lecture
Lovett, A, Richard. "Yellowstone Eruptions more Numerous then Thought?". National Geographic. May, 2011. http://news.nationalgeographic.com/news/2012/05/120501-yellowstone-supervolcano-eruption-science-ellis/
Yellowstone Wiki. "Vegetation". http://www.yellowstonewiki.com/wiki/Vegetation





No comments:

Post a Comment