Geo 111-501

Brian Narum

Front Range Community College

Park HistoryPark was originally named Great Sand Dunes National Monument in 1932. It

was preserved by residents of Alamosa so that gold mining and

cement makers would not decimate the area. It was renamed Great Sand Dunes National Park and Preserve in 2003 and named a National Park. It

covers 84,997 acres and contains the the highest dunes in North America

some rising up over 750 feet. It is high desert that sits in the San Luis

Valley. In addition to the sand dunes it also has alpine lakes, 6 mountain

peaks that exceed 13,000 feet, wetlands, and pine and spruce forests. To the east of the park boarders the Sangre De Cristo

Mountain Range.

Location: 37°43 58′ ″N 105°30 44″′ W11999 Highway 150 Mosca, CO 81146-

9798

Located in Alamosa County in Colorado. The nearest city is Alamosa in the South

Western part of Colorado.

Picture National Parks Service, Last updated 4/21/2012.

Formation of the Great Sand Dunes Pictures from National Parks Service Last updated 4/21/2012

The theory on how the sand dunes formed is based on research from 2007 called On the origin and age of the Great Sand Dunes, Colorado by R. Madole. After a large volcano exploded leaving a large crater and large deposits of ash. The San Juan mountains were created after that from rifting and rotation of plates. The crater became a lake from the rain and snow deposits and fed through water migration to the lake. The lake dried up and left behind the sand sheet that makes up the dry lake bed. The loose material creates the dunes from the predominant winds. However the reason that they grow to such great heights is the storm winds that blow across the mountain range, causing the dunes to grow vertically. The predominant winds also die out as they come over the mountain range. This keeps the sand and material in the valley and the sand recycling in the process. Making these dunes the largest in North America. New material is fed through two seasonal rivers the Medano and Sand Creeks. Material flows away from the sand dunes and is deposited. When the creeks dry up for the season the material now can be recycled back into the sand dunes. http://www.nps.gov/grsa/naturescience/sanddunes.htm

Singing Sand Dunes

http://www.nps.gov/grsa/naturescience/sanddunes.htm

Singing sand dunes are not unique to just the Great Sand Dune National Park and Preserve. It can be repeated by anyone and no one. The singing of the dunes is caused by slope failure of the angle of repose. The dune has an avalanche of sand that causes air around the sand to be compacted and causes the audible sounds that can be heard in link below. The avalanche can be caused by people like that in the picture or caused by the wind blowing hard enough to get the sand moving like that as pictured. The sounds can be created by just a little bit of sound or can be very loud with the more sand the more movement of air it creates. It is just like how the speakers in your car work. As the subwoofer of your speaker moves with the electric impulses from your stereo it vibrates the air around it into waves. The waves are then picked up by your ears and converted back into electric signals that your brain can interpret.

Resources “Great Sand Dunes National Park and Preserve.” A Reference and Travel Guide for the Rocky Mountain States. Accessed April 02, 2012. http://sangres.com/sanddunes. National Parks Service. Accessed April 02,

2012. http://www.nps.gov/grsa/planyourvisit/maps.htm.

"Great Sand Dunes National Park." Wikipedia. Accessed April 02, 2012. http://en.wikipedia.org/wiki/

Great_Sand_Dunes_National_Park.

"Alamosa Convention and Visitors Bureau - Great Sand Dunes National Park." Alamosa Convention and Visitors

Bureau. Accessed April 02, 2012. http://www.alamosa.org

/things-to-do/scenic- wonders/the-great-sand-dunes."Great Sand Dunes National Park." National

Geographic. Accessed April 02, 2012. http://travel.nationalgeographic.com

/ travel/national-parks/great-sand-dunes- national-park/.

Madole, R., J. Romig, J. Aleinikoff, D. Vansistine, and E. Yacob. "On the Origin and Age

of the Great Sand Dunes, Colorado." Geomorphology 99, no. 1-4 (2008): 99-119. doi:10.1016/j.geomorph.2007.10.006.