Sand Dunes Shouldn’t Exist (Here’s Why They Do)

White Sands National Monument (at 3:00 is a brief mention of it in this video) hosts the most consequential dune field in New Mexico.  It is worthy of individual study due to its composition of gypsum, rather than the typical quartz.

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There is the smaller Rio Salado Dune Field in central Nex Mexico, with the seasonally-dry Rio Grande riverbed providing the source of these sands.  Interestingly in this report, the heavy mineral suite is more typical of crystalline rocks (Evans, 1963), perhaps owing to intrusive and extrusive igneous rocks and metamorphic rocks in the Rio Grande watershed.

Other nearby sandhills are found south of New Mexico, near I-20 are the Monahans Sandhills, southwest of Odessa, TX.

North of New Mexico, in Colorado are the Great Sand Dunes National Park and Preserve, northeast of Alamosa, Colorado with the stunning Sangre de Cristo Mountains in the background.

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Sources (More to be added):

George C. Evans, 1963, GEOLOGY AND SEDIMENTATION ALONG THE LOWER RIO SALADO IN NEW MEXICO pp. 209-216 in Socorro Region, Kuellmer, F. J.; [ed.], New Mexico Geological Society 14th Annual Fall Field Conference Guidebook.