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Remote sensing and field evidence are used to describe sand deposits found in associated pathways of emplacement in the eastern Mojave Desert. Two separate pathways are identified here: one extending eastward from the Bristol Playa through the Cadiz and Danby Playas and Rice Valley to the Colorado River, and a second parallel path extending eastward from Dale Playa through the Palen and Ford Playas to the Mule Mountains near the Colorado River. The preferential location of sand ramps on the west slopes of mountains along each path suggests that the eastward moving, wind-driven sand was not confined by topographic divides between separate drainage basins around the individual playas and valleys. Sediment analysis of selected samples shows that there are discreet associations of sand characteristics along the sand pathways, with an inferred similarity between the stabilized (vegetated) sands in Rice Valley, west of the Colorado River, and stabilized sand dunes on Cactus Plain and La Posa Plain in Ajizona, east of the Colorado River. Sand transport along the paths appears to have been episodic, based on multiple paleosols present in several dissected sand ramps. Future testing of the sand transport path hypothesis will require additional sediment analyses, spectral studies of remote sensing data, and obtaining dates for selected soil horizons along the sand paths.

The Wahiba Sand Sea in the Sultanate of Oman is composed of two physiographic units that can be roughly divided into northern and southern regions. The Northern Wahiba is predominantly a large megaridge system, whereas the Southern Wahiba mostly comprises linear dunes, sand sheets, and nabkha fields. Although the dunes of the two regions are of different ages, it has previously been hypothesized that their sands were derived primarily from the same source, namely coastal sands. However, mineralogical, geochemical, and grain-size data in this study suggest that the two regions have different sources. The Northern Wahiba sands have a high composition of mafic minerals and came primarily from local wadis that drain the adjacent Hajar Mountains. One of the prominent wadi sources is presently buried under sands of the Southern Wahiba, eliminating it as a current source of the Northern Wahiba. The Southern Wahiba sands have a more mineralogically mature, quartz-rich composition and are derived from separate sources, likely to be the Oman coast or adjacent sabkha plains. Previous researchers used carbonate sand, present throughout the sand sea, to infer that the coast was the major source of sands in the entire sand sea. However, geochemical evidence suggests that the carbonate grains in the sand sea originated from the two contrasting sources along with the other grains. Carbonate grains in the Northern Wahiba are derived from wadis that drain limestones in the Hajar Mountains whereas carbonate grains in the Southern Wahiba are probably reworked from underlying aeolianites and coastal sands.