[Coral-List] Atolls and SL rise

[Eugene Shinn]

Geologically speaking atolls have survived fluctuating sea levels 
many times in the past. In fact their very shape and architecture 
reflects rising sea level. Remember, 125 Ka world-wide sea level was 
anywhere between 26 and 90 ft above present level and since then has 
fluctuated up and down several time and was at least 400 ft below 
present  just 18 Ka and then the polar ice melted and sea level 
jumped up rapidly and slowed around 3 Ka and is still rising. Humans 
had nothing to do with that rise. Is there any reason to believe it 
may not continue to rise up as much as it did in the past? Atolls 
look like what we call atolls because sea level has not been stable 
long enough for the central lagoons to fill in with sediment. Atolls 
are thus a product of a fast growing coral rim, marine cementation 
and sea level rising faster than the lagoon can fill in.  Gene
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No Rocks, No Water, No Ecosystem (EAS)
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E. A. Shinn, Courtesy Professor
University of South Florida
Marine Science Center (room 204)
140 Seventh Avenue South
St. Petersburg, FL 33701
<eshinn at marine.usf.edu>
Tel 727 553-1158---------------------------------- 
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