Posted on 03/09/2014 4:33:46 PM PDT by SunkenCiv
One thousand years ago, on a floodplain of the Mississippi River near modern-day St. Louis, the massive Native American city known today as Cahokia sprang suddenly into existence. Three hundred years later it was virtually deserted...
While analyzing cores from Horseshoe Lake, an oxbow lake that separated from the Mississippi River some 1,700 years ago, Munoz's team discovered a layer of silty clay 19 centimeters (7.5 inches) thick deposited by a massive ancient flood.
It's unlikely that the ancient floodwaters were high enough to inundate the ten-story mound at Cahokia's center, a structure now called Monk's Mound... But a flood of such magnitude would have devastated croplands and residential areas, and may have made it impossible for a population numbering as many as 15,000 to continue inhabiting the area...
Analysis of pollen deposits in the sediment cores from Horseshoe Lake shows an intensification of farming, accompanied by rapid deforestation, starting around 450..., with corn cultivation peaking between 900 and 1200... Then the cores reveal the flood event, followed by a decline in corn cultivation. By 1350..., the pollen record shows, agriculture there had essentially ceased.
Munoz, a geographer who specializes in the study of pollen records, noticed that very little pollen research had been done in the American Southeast, where the Mississippian culture flourished. "And we didn't really have any studies outside big archaeological sites," he said. So when he saw Horseshoe Lake right next to Cahokia, he thought it was worth a shot...
But he had no idea they might find such a big piece of the puzzle. "When we realized we were looking at a flood, and that it fell right at this key time in Cahokia's history, it was very exciting."
(Excerpt) Read more at news.nationalgeographic.com ...
I wonder if an earthquake on the New Madrid fault triggered a disturbance in the Mississippi River causing a flood.
disagree. primary impediment to turning the deserts green is the cost of desalinizing and transporting desalinated water inland from desert coasts.
The big problem I see is future increases in electricity costs as the lefties work to destroy the coal industry and coal fired generators. And the anti-fracking Luddites want to reverse the expansion of the natural gas industry.
Some interesting info on the 1993 flood. http://www.nwrfc.noaa.gov/floods/papers/oh_2/great.htm
Thanks EVO X.
Assuming it’s a worthwhile goal, the cost-cutting to take place will be in that expense.
The coal industry is getting closer to the implosion point, thanks to Slick and Zero.
Detroit started to bleed in the 1960s, after the late 1950s auto industry peak (first 10 million vehicle year, and the last one for a long while), followed by the riots, white flight, and the disaster that was Coleman Young.
Cahokia got flooded out, and the flood killed the crops in the field. It never recovered.
Maybe my point was a bit too abstract. Humans don't learn from past natural disasters (witness Fukushima where ancient stone monuments on the hillsides warn not to build below their elevation because of tsunami danger.)
Neither do they learn from past political and cultural folly. Detroit is just one example out of of hundreds in which human greed/vanity/stupidity/whatever have led to severe decline and often destruction. Neither do cultures as a whole learn much from the past. Right now I'm getting a strong sense of 1930s deja vu all over again.
The fire was in a satellite town or “suburb” 10 km away; the main mound city where the huge Monk’s Mound is was not burned.
Still, that burned compound to the west was very important for some reason, as was the Emerald Mound complex to the east.
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