What geologic features allowed the stovepipe dunes to form?

Dunes are formed through the interaction of mountains and wind. The wind picks up quartz grains from the mountains in the area to form the dunes and these are reshaped by the same process over time.

Sand dunes are geological features that are commonly formed in the areas where there is abundant concentration of sands. This includes the bars in the rivers, deserts, and coastal beaches. The agent that is responsible for dune formation is wind. The sand size particles due to high wind get eroded from different places and transported to a place where the accumulation of sand is more.  

It is a pile of sand and it has two sides, namely the wind-ward side, the direction from where the wind blows and the flip side, where there are no wind and sand grains deposited.

The stovepipe dunes in California have formed in this way.

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