Geography-Desert

How is an arch formed? - ANS An arch is formed by erosion. What are clay pans? - ANS Clay pans are low-lying sections of ground that stay muddy and wet for some time. Why are there rippled surfaces on transverse dunes? - ANS There are rippled surfaces in transverse dunes as a result of a gentle breeze blowing in the one direction. What is an oasis? - ANS An oasis is a fertile spot in a desert which receives water from underground supplies. What is a mesa? - ANS A mesa is a plateau-like section of higher land with a flat top and steep sides. The flat top was once ground level but was weathered away by erosion. How are sand dunes formed? - ANS Sand dunes are formed as small mounds of sand that collect around an object such as a rock. As the dunes grow larger, they are shaped by wind. What is an inselberg? - ANS An inselberg is a solid rock formation that was once below ground level. As a result of the softer sand eroding, the rock became more prominent such as Uluru or Ayer's Rock. What is a chimney? - ANS A chimney is the pillar-like remains of a butte. How are star dunes produced? - ANS Star dunes are produced by wind gusts that swirl in from all directions. How are salt pans formed? - ANS Salt pans are formed when water in a playa lake evaporates, leaving a layer of salt on the surface. What is an arch or window? - ANS An arch or window is an opening in a rock wall that has been carved out by erosion. When are crescent shaped barchan dunes made? - ANS Crescent shaped barchan dunes are made when sand cover is fairly light. What is a butte? - ANS A butte is shaped like a castle or tower and is the remaining. Solid core of what was once a mesa. Where are the majority of the world's deserts found? - ANS The majority of the world's deserts are found between the Tropic of Cancer and the Tropic of Capricorn. Where do the hot regions between the Tropic of Cancer and Tropic of Capricorn occur? - ANS These hot regions occur between 30degrees N and 30 degrees S on either side of the equator. How much of the earth's surface is covered in deserts? - ANS One third (or 33 percent) of the earth's surface is covered in deserts. Where are the most important deserts located in the world? - ANS The most important deserts are found on each of the main continents including Australia, Africa, Asia, North America and South America.