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Climate Change today...????
Climate Change
Did the Chesapeake Bay bolide affect the location of
Chesapeake Bay itself? We know that the bay is nowhere near 35 million years
old. In fact, as late as 18,000 years ago, the
bay region was dry land; the last great ice sheet was at its maximum over
North America, and sea level was about 200 m lower than at present. This sea level exposed the area that now is the bay
bottom and continental shelf. With sea level this low, the major east coast
rivers had to cut narrow valleys across the region all the way to the shelf
edge. About 10,000 years ago, however, the ice
sheets began to melt rapidly, causing sea level
to rise and flood the shelf and the coastal river valleys. The flooded
valleys became the major modern estuaries, like Delaware Bay and Chesapeake
Bay. The rivers of the Chesapeake region converged at a location directly
over the buried crater. In short, the impact crater created a long-lasting
topographic depression, which helped determine the eventual location of
Chesapeake Bay.
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