Sediments show bipolar melting cycle.Evidence harvested from ocean sediments suggests that the North and South Poles North and South Poles figurative ends of the earth. [Geography: Misc.] See : Remoteness have experienced regular periods of significant melting simultaneously. A 600-meter core drilled from a site off Greenland's eastern coast and a 200-m core from off Antarctica reveal several episodes of particularly high sediment sediment, mineral or organic particles that are deposited by the action of wind, water, or glacial ice. These sediments can eventually form sedimentary rocks (see rock). accumulation in the past 3 million years, says Kristen E. St. John, a geologist at Appalachian State University History Appalachian State University began in the summer of 1899 when a group of citizens of Watauga County, NC, under the leadership of D.D. Dougherty and B.B. Dougherty, began a movement to establish a good school in Boone, NC. Land was donated by D.B. in Boone, N.C. These spates of high sedimentation sedimentation In geology, the process of deposition of a solid material from a state of suspension or solution in a fluid (usually air or water). Broadly defined it also includes deposits from glacial ice and materials collected under the effect of gravity alone, as in talus occurred about 0.9 million, 1.9 million, and 2.8 million years ago and match periods of increased sea level. During these times, about twice the average amount of coarse sand fell onto the ocean floor at the drilling sites. St. John says the increased sandfall probably occurred when sand-riddled ice sheets disintegrated into flotillas of icebergs. As these melted melt v. melt·ed, melt·ing, melts v.intr. 1. To be changed from a solid to a liquid state especially by the application of heat. 2. and drifted toward lower latitudes, they dropped the sand to the ocean bottom, she contends. Many factors can affect the rate of sedimentation at high-latitude sites, including the temperature and speed of ocean currents and the debris content of the icebergs. St. John contends that the matching patterns and rates of sedimentation at sites near the two poles suggest a worldwide phenomenon, such as a large-scale climate change. |
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