Describe the process of glacial movement
What will be an ideal response?
Glacial ice behaves as a plastic; it distorts and flows in its underlying portions in response to the weight and pressure of the overlying snow and the degree of slope upon which it resides. The rate of flow varies from very little flow to several kilometers per year. The greatest movement within a valley glacier occurs internally—below the rigid surface layer. The base creeps and slides along, with varying speeds depending on temperature and the presence of lubricating water beneath the ice. This is slower than the internal flow, though, so the upper portion flows ahead of the lower portion. Glaciers may also advance more rapidly (albeit still slowly) via a glacier surge. A glacier surge may result from the buildup of water pressure under the glacier or due to a soft bed (a layer of water saturated sediment under the glacier).
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Swidden agriculture involves
A) burning the natural vegetation to release nutrients. B) clear-cutting the forest for timber C) animal husbandry. D) exporting high value agricultural goods. E) the production of yams for export.
Geotagged photos can be taken with a cell phone as long as the cell phone is GPS-integrated.
Answer the following statement true (T) or false (F)
Magnetic stripes in oceanic basalts are ____________________ and ____________________ around
ocean ridges. Fill in the blank(s) with the appropriate word(s).
The level of decaying organic matter in water is indicated by what measure?
A) fecal coliform B) eutrophication index C) biochemical oxygen demand D) nitrogen and phosphorus