The Strange Fields of Sand Dunes in Alaska; A Geologic Oddity

Описание: Within the Arctic Circle are a series of vast sand dunes which once covered more than 300 square miles in dunes up to 100 feet in height. What I am referring to are the Great and Little Kobuk Sand Dunes in Kobuk Valley National Park, where the Great Kobuk Sand Dunes today cover an area of 25 square miles and still contain 100 foot high dunes. These dunes did not form due to an ancient warm climate but rather the opposite; they formed due to thick glaciers.

Thumbnail Photo Credit: This work "ThumbnailKobukSand1", is a derivative of a photo (resized, cropped, image brightness increased, text overlay, graphics overlay) from "Setting Sun over Ahnewetut Creek", by: Western Arctic National Parklands, nps_wear, 2007, Posted on Flickr, Flickr account link: https://www.flickr.com/photos/nps_wear/, Photo link: https://www.flickr.com/photos/nps_wea..., CC BY 2.0. "ThumbnailKobukSand1" is used & licensed under CC BY 2.0 by    / geologyhub  

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Sources/Citations:
[1] National Parks Service
[2] Briner, Jason & Tulenko, Joseph & Kaufman, Darrell & Baichtal, James & Lesnek, Alia. (2017). The last deglaciation of Alaska. Cuadernos de Investigación Geográfica. 43. 10.18172/cig.3229. CC BY 4.0
[3] Wentworth, Chester Keeler. “A Scale of Grade and Class Terms for Clastic Sediments.” The Journal of Geology 30 (1922): 377 - 392.
https://doi.org/10.1086/622910
[4] U.S. Geological Survey
[5] NASA Worldview, EOSDIS Worldview, (Satellite imagery: Terra / MODIS) at https://worldview.earthdata.nasa.gov/

0:00 Alaskan Sand Dunes
1:08 Glaciers
2:34 Decrease in Size
3:15 Conclusion