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Download Wind Processes and Desert Landscapes
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Wind Processes and Desert Landscapes Arid and Semiarid Regions The Topography of Arid Lands Sparse Vegetation Running Water in Waterless Regions The Work of Wind Ergs, Regs, and Hamadas Flat areas Fluvial Processes Impermeable Rocks or Permeable Sediments Flash Floods Fast collection of water at valley floor High Q (discharge) Desert Landforms Dry Stream Beds Wash – arroyo - wadi Sediments - Alluvium Ephemeral/Intermittent Arroyo Playa – Dry Lake Alluvial Fan Death Valley Inselbergs/Bornhardts Erosion-Resistant Rock Bornhardt – rounded inselburg The Work of Wind Eolian Erosion/Transportation Eolian Depositional Landforms Loess Deposits Ventifacts Wind abrasion Yardang Streamlined by wind Sand Transport Sand Transport Sandy Regions of the World Sediment Transport by Wind Formation of Cross Bedding Dune Cross Section Major Dune Forms Wind direction & sand supply Desert Dunes Barchan Sand starved Constant direction Seif Two dominant wind directions Common outside USA Star Dunes Sandy Giants of Desert Lithified Cross Bedding Loess Regions of the World Fine grain – lacks stratification From deserts or glaciers Soil component Unique Desert Landforms Erg Sand Sea Sahara Marzūq Blowout / Deflation Hollow Oasis - Deflation down to groundwater Reg Stony Desert Deflation Desert Pavement Hamada Rock Surface – Exposed Bedrock Can be similar to Reg but not from deflation Term not as common in usage in USA Differential Weathering Basin-and-Range Landscape Mesa & Scarp Zion National Park B Climate Colorado Plateau Primarily Sandstone Base of shale Cap of Limestone
