The Mississippi River is the second longest river in North America. Bodies of water from 31 contiguous states drain into the Mississippi. Its source is in Minnesota and ends in the Gulf of Mexico (Friends of the Miss.)
The Mississippi originates in the area of northwestern Minnesota, as it flows down it receives water from other rivers such as the St. Croix. The Mississippi travels south for 2,530 miles until it reaches its final destination at its Delta. This river’s Delta is characterized by it alluvial deposition in deep waters.
The Mississippi River Delta Basin consists of approximately 521,000 acres of land and shallow estuarine water area. Natural channel banks, and a large area of freshwater marsh are prominent features. The Mississippi also comprises several natural lakes such as Lake Pepin.
Over millions of years the seas have risen and fallen, and the Mississippi River’s features changed. During the Ice Age, the Laurentide Ice Sheet mostly shaped the River’s current. As the ice sheet melted, movements from the Glaciers deposited and till in the Mississippi soil. These sediments left the Mississippi region fertile.
As the temporary rivers formed during this ice age found outlets in other bodies of water, they left a depression with sediments indicating to this ice era. Also responsible for the change of certain Mississippi features were created by ecological pressures, which blocked the River in a portion of today’s state of Illinois. (Wikipedia)
This is our modern soil, which is sediment and till left from the movement of glaciers. It can be 100 feet thick in some areas. An approximately 30 ft deep layer of limestone dating to the Ordovician Period Ocean covers the area. There is also a Glenwood Formation, which consists of shale remains dating from the Ordovician Sea. Another layer of softer sedimentary rock underlies this area is the Saint Peter Sandstone (CWPPRA).
References
CWPPRA Retrieved on 1/12/2012 from: http://lacoast.gov/new/About/Basin_data/mr/Default.aspx
Friends of the Mississippi River Retrieved on 1/12/2012 from http://www.fmr.org/participate/ongoing/gorge_stewards/history
Wikipedia Retrieved on 1.12.2012 http://en.wikipedia.org/wiki/Mississippi_River
