Petrified Sand Dunes - Arches National Park This vast area was once covered by extensive sand dunes. Some 200 million years ago, winds from the northwest carried tons of fine-grained sand into this area, creating an immense desert. Over time, the sand drifts were covered by other layers of sediment, compressed and cemented by quartz and calcite into Navajo Sandstone.

圖片編號： 116796011
拍攝者： mickeybay