christof139
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Here Mr. Lensman, read some more about the Mighty Miss before you start telling me I don't know what I am talking about. Here in this excerpt you will see that the Miss. River scours holes a hundred and more feet in depth in its bends near the river banks, and its bed in the MAIN CHANNEL is over 170-feet below sea level at New Orleans. It is a deep and dangerous river as is explained below.
If I can find the geologic/Topological Cross Section of the Miss. River at Vicksburg at the time of the ACW, you will find that I am 110% correct as to its depth in the main channel being near or up to 60-feet deep in spots, then I will post this site address for you to peruse. Forget Wikipedia please.
Read and understand what you glaze over and then erroneoulsy and hastily post before you tell me I don't know what I am talking about please.
Sincerely, Mr. Chris, a defunct Geologist with it of a memory.
http://www.bigeasy.com/features/captain.html
The Mississippi never lies at rest. It roils. It follows no set course. Its waters and currents are not uniform. Rather, it moves south in layers and whorls, like an uncoiling rope made up of a multitude of discreet fibers, each one following an independent and unpredictable path, each one separately and together capable of snapping like a whip. It never has one current, one velocity. Even when the River is not in flood, one can sometimes see the surface in one spot one to two feet higher that the surface close by, while the water swirls about, as if trying to devour itself. Eddies of gigantic dimensions can develop, sometimes accompanied by great spiraling holes in the water. (Eddies have been observed running upstream at seven miles an hour and extending half across the River, whirling and foaming like a whirlpool.)
The River's sinuosity itself generates enormous force. The Mississippi snakes seaward in a continual series of S curves that sometimes approach 180 degrees. The collision of River and earth at these bends creates tremendous turbulence: currents can drive straight down to the bottom of the River, sucking at whatever lies on the surface, scouring out holes often several hundred feet deep. Thus the Mississippi is a series of deep pools and shallow "crossings" and the movement of water from depth to shallows adds still further force and complexity. High water — a flood — makes River dynamics more volatile and enigmatic. IN some parts of the River high water raises the surface 70 feet above low water. By raising the surface in relation to sea level, high water can thus increase the slope of the River by 25% or more. And velocity depends upon the slope. The River's main current can reach 9 miles an hour, while some of the River's other currents can move much faster. During floods, measurable effects of an approaching flood crest can roar downriver at almost 18 miles an hour.
And for the last 450 miles of the Mississippi's flow, the riverbed lies below sea level — 15% below sea level at Vicksburg, well over 170 feet below sea level at New Orleans. For this 450 miles the water on the bottom has no reason to flow at all. But the water above it does. This creates a tumbling effect as water spills over itself, like an enormous ever-breaking internal wave. The tumbling effect can attack a riverbank — or a flood control levee — like a buzz saw. But the final complexity of the lower Mississippi is its sediment load, and understanding it is the key not only to understanding how to control the River, but also to understanding how the soil of the Delta became to be so rich, which, without it, the blues could not have been born. Every day the River deposits between several hundred thousand and several million tons of earth in the Gulf of Mexico. At least some geologists put this figure even higher historically, at an average of more than 2 million tons a day.
By geological standards the lower Mississippi is a young, even infant stream, and runs through what is known as the Mississippi Embayment, a declivity covering approximately 35,000 square miles that begins 30 miles north of Cairo to Cape Giradeau, Missouri — geologically the true head of the Mississippi Delta — and extends to the Gulf of Mexico. At one time the Gulf itself reached to Cape Giradeau, then sea level fell. Over thousands of years the River and its tributaries have poured 1,280 cubic miles of sediment — the equivalent of 1,280 separate mountains of earth, each one mile high, one mile wide, and a mile long — into this declivity. Aided by the falling sea level, this sediment filled in the embayment and made land. Throughout the Mississippi's alluvial valley, this sedimentary deposit has an average thickness of 132 feet; in some areas the deposits reach down 350 feet. It's weight is great enough that some geologists believe its downward pressure pushed up surrounding land, thus creating hills.
< Message edited by christof139 -- 4/14/2007 7:21:53 PM >
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'What is more amazing, is that amongst all those approaching enemies there is not one named Gisgo.' Hannibal Barcid (or Barca) to Gisgo, a Greek staff officer, Cannae.
That's the CSS North Carolina BB-55
Boris Badanov, looking for Natasha Goodenov
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no USA blockades anymore? - 
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