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North Dakota Eclectics

Red River Valley
The Red River Valley is in the eastern part of North Dakota, extending into Minnesota. This part of the state is almost as level as a floor, sloping about one foot a mile to the north, and less than that to the east. The Red River Valley has been the most fertile part of North Dakota. Except along the streams and the Pembina Escarpment, there are no trees in the Red River Valley.

On the North Dakota side of the Red River, the valley is about forty miles wide at the state's northern boundary, narrowing slightly as it moves south, narrowing rapidly to about ten miles in width at the South Dakota border.

The glaciers were formed many years ago as snow piled higher and higher, year after year, melting only a little during the summer, piling up to a point where the pressure of the snow changed it to ice, forming a glacier that covered northern and eastern Canada, to the west and south. It came down from the north as a huge mass of ice, as much as two miles thick, moving a few inches or feet each day. The weight of the glacier was several hundred tons per square foot, so it would gouge out the soil over which it passed, carrying much of the soil along with it, depositing it elsewhere, as the glacial ice melted. Due to this process, most of the topsoil in the glaciated part of North Dakota had been carried there from Canada. As the glacier moved up the Red River Valley, it deepened the valley, as it picked up and carried rocks and soil south, as far as Nebraska.

As the glaciers melted, they retreated north. The water from the melting ice flowed south while the southern edge of the glacier was in Nebraska and South Dakota. However, when the glacier retreated into North Dakota and the Red River Valley, the water from the melting ice was trapped, forming a lake that was later named Lake Agassiz. Initially, the overflow from the lake went south but, as its surface lowered, it drained to the north. As the surface of the lake was lowered through the years, new beaches were formed at the margins of the lake. These beaches are the only irregularities in the otherwise level floor of the Red River Valley.

Wherever a river flows into a lake or other body of water, the rate of the flow of the water is reduced, and at some point it stops completely. At the point where the water stops flowing, it no longer has the power to carry sediment, and drops it, with the coarsest particles being dropped first, and the finer particles carried further along. The pile-up at the mouth of a river is called a delta, of which there are several along the western edge of the Red River Valley.

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