Unique Facts
How Great Sand Dunes National Park Was Formed
Scientists change their minds often about how the Great Sand Dunes were formed because of new information and evidence, but this is the newest information on it. About 25 million years ago, the largest volcanic eruption in history, the eruption of La Garita Caldera, took place and the San Juan Mountains were formed out of all that lava. Then, during the ice ages, glaciers slid down the mountain and made sand as they went. Next, streams in the mountains made lots of erosion which made sand go down to the Rio Grande for a long time. This helped to spread out the sand all over the valley floor. Over hundreds of years, the sand was being pushed from all directions by the wind which made the big sand dunes. This is still happening today, although it is happening a lot more gradually. To see this in an animation, click on this link: http://www.nps.gov/grsa/naturescience/sanddunes.htm
Learn A New Language!
- The Ute tribe's name for the Great Sand Dunes was "Sowapophe-uvehe," which meant "the land that moves back and forth".
- The Jicarilla Apache tribe's word for the Great Sand Dunes was "Sei-Anyedi," which meant "it goes up and down".