Kelso Dunes represent part of a much larger sand transport system, which includes the nearby Devils Playground region. The composition and morphology of the sand grains indicate that most originated from the Mojave River sink near Afton Canyon, which lies to the west of the dunes' current location. The sand has accumulated at the southeastern end of the Soda Lake-Kelso basin, where the Granite Mountains and Providence Mountains form a barrier to prevailing winds. At present, only the area around the Mojave River sink and the westernmost parts of Devil's Playground are receiving new sand through this system; sand is no longer accumulating at Kelso Dunes itself.