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ICE AGES: - The impact of the ice ages and inter-glacial effects on the rise and fall of ocean levels and the earth readjustments to the departure of the ice cap cannot be over-looked in the human historical picture. Research in the area is far greater than in the recent past and we can learn what might have happened to earlier civilizations on earth. Atlantis is a given name for a civilization that inhabited many islands and coastal regions Wholesale Mike White Jersey , in my mind. The idea of one central location makes little sense when one considers such things as Ice Ages and changes in the flow of the Gulf Stream and climate that resulted. Because it lasted for from 30,000 to 100,000 years and may have co-existed with other civilizations rising and falling it is most inauspicious to debate one specific time when it was in Tara or Crete or the Azores or Bimini or even Finias. That seems to be the usual debate among the over 25,000 books written about just this one lost civilization. As long as people don't integrate all facts they inevitably just come up with theories to fit pet or prevailing concepts. In Gateway to Atlantis Wholesale Dalton Schultz Jersey , 'The Search for the source of a lost Civilization' we see a far better scholar who is doing the right kind of investigation. Mapping of the ocean bottoms and geological understandings as well as studying glacial deposits and tree rings gives a better picture of history than history books.


"In 1960 a scientific paper by Wallace S. Broecker and his colleagues Maurice Ewing and Bruce C. Heezen, of Lamont Geological Observatory at Columbia University, Palisades, New York Wholesale Dorance Armstrong Jr. Jersey , appeared in the 'American Journal of Science'. Entitled 'Evidence for an Abrupt Change in Climate close to 11,000 years ago', it advanced the theory that a 'number of geographically isolated systems suggested that the warming of world-wide climate which occurred at the close of Wisconsin glacial times was extremely abrupt. (3)


By examining sediment cores taken from various deep-sea locations, Broecker and his team were able to demonstrate that around c. 9000 BC. the surface water temperature of the Atlantic Ocean increased by between six and ten degrees centigrade Wholesale Michael Gallup Jersey , (4) enough to alter its entire ecosystem. More significantly, it was found that the bottom waters of the Cariaco Trench in the Caribbean Sea, off Venezuela, suddenly stagnated Wholesale Connor Williams Jersey , {The Gulf Stream being sent back south from hitting the land around the Azores when the water level was lower suddenly started warming the Iceland and British Isles regions, again.} showing that an abrupt change in water circulation had taken place coincident to the warming of the oceans. (5) Additionally, the silt deposits washing into the Gulf of Mexico from the Mississippi Valley abruptly halted and were retained in the delta and valleys, as the waters from the glacier-bound Great Lakes switched direction and began draining through the previously frozen northern outlets. (6) With extreme rapidity Wholesale Leighton Vander Esch Jersey , the water levels of these lakes shrank from maximum volume, down to the much lower level they occupy today. (7)


Among the data drawn on by Broecker and his team to make their findings was the work conducted in 1957 by Cesare Emiliani of the Department of Geology at the University of Miami. He found that deep-sea cores displayed clear evidence of an abrupt temperature turn around in 9000 BC. was responsible for the other changes set out by Broecker et al. (8) However, since other cores examined by Emiliani had not shown the same rapid transition, he decided that the anomalous cores lacked vital sediment layers covering a period of several thousand years of ecological history Wholesale Xavier Woods Jersey , and so dismissed them as unreliable. (9) Yet Broecker and his colleagues disputed Emiliani's interpretation of the results. They could find no reason to suppose that key sediment layers could have been lost in the manner suggested. As a consequence, they reinstated Emiliani's controversial findings as crucial evidence of a major shift in oceanic temperatures around 11,000 years ago. (10)


Although Broecker et al seemed keen to promote a date of c. 9000 BC for the rapid transition from glacial to post-glacial ages, there are indications that this event did not occur until a slightly later period. At least three lake sites in the Great Basin region revealed carbon-14 dates around 8000 BC for a maximum water level shortly 'before' they experienced a sudden desiccation after the withdrawal of the ice sheets. (11) In addition to this Wholesale Jourdan Lewis Jersey , marine shells from the St. Lawrence Valley, which provided evidence of an invasion of seawater coincident to a rapid ice retreat, frequently produced dates 'post' 9000 BC. (12)


Broecker and his colleagues accepted the presence of these much lower dates and suggested that the whole matter was complicated by the fact that there had been an estimated 200-year resurgence of glacial conditions, known as the Valders re-advance Wholesale Byron Jones Jersey , around the mid-ninth millenium BC. They therefore acknowledged that their own findings might in fact relate to the recession of the ice fields after this time, bringing the dates of their suggested 'major fluctuation in climate' and the 'sharp change in oceanic conditions' down to well below c. 9000 BC. (13)


THE EVIDENCE OF POLLEN SPECTRA


Further evidence that dramatic changes accompanied the transition from glacial to post-glacial ages came from the work of Herbert E. Wright Jnr, of the School of Earth Sciences at the University of Minnesota, Minneapolis Wholesale Maliek Collins Jersey , (14) and J Gordon Ogden III of the Department of Botany and Bacteriology at the Ohio Wesleyan University, Delaware. (15) Both examined the pollen spectra range from sediment cores taken from various lake sites in the Great Lakes area and found they provided clear evidence of an abrupt shift in flora at the end of glaciation. The spruce forests that had thrived in the cold harsh climate for many thousands of years were supplanted swiftly, first by pine and then by mixed hardwood fo

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