Composition and Creation of The Dune Fields
The white to tan sands of the dune fields are almost pure silica. On average, the sand contains 90-95% quartz and 5-10% mixed rock grains.
The particle shapes are nodular and spheroid. they were formed by airflow erosion of rocks that created small fragments that were then carried away by the wind, to be deposited in natural land depressions. Another factor assisting in the formation of the dunes is the abrupt changes of temperature that exist in the desert, which assisted in the breaking up of surface rock into sand grains.
Read more about this topic: Samalayuca Dunes
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