The Coteau des Prairies is a plateau

Plateau

In geology and earth science, a plateau , also called a high plain or tableland, is an area of highland, usually consisting of relatively flat terrain. A highly eroded plateau is called a dissected plateau...

 approximately 200 miles in length and 100 miles in width (320 by 160 km), rising from the prairie

Prairie

Prairies are considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and grasses, herbs, and shrubs, rather than trees, as the dominant vegetation type...

 flatlands in eastern South Dakota

South Dakota

South Dakota is a state located in the Midwestern region of the United States. It is named after the Lakota and Dakota Sioux American Indian tribes. Once a part of Dakota Territory, South Dakota became a state on November 2, 1889. The state has an area of and an estimated population of just over...

, southwestern Minnesota

Minnesota

Minnesota is a U.S. state located in the Midwestern United States. The twelfth largest state of the U.S., it is the twenty-first most populous, with 5.3 million residents. Minnesota was carved out of the eastern half of the Minnesota Territory and admitted to the Union as the thirty-second state...

, and northwestern Iowa

Iowa

Iowa is a state located in the Midwestern United States, an area often referred to as the "American Heartland". It derives its name from the Ioway people, one of the many American Indian tribes that occupied the state at the time of European exploration. Iowa was a part of the French colony of New...

 in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. The southeast portion of the Coteau comprises one of the distinct regions of Minnesota, known as Buffalo Ridge

Buffalo Ridge

Buffalo Ridge is a large expanse of rolling hills in the southeastern part of the larger Coteau des Prairies. It stands 1,995 feet above sea level. The Buffalo Ridge is sixty miles long and runs through Lincoln County, Pipestone County, Murray County, and Nobles County in the southwest...

.

The flatiron

Flatiron

Flatiron or flat iron can mean several things:*An old term for a clothes iron*A wedge-shaped building:**The Flatiron Building in New York City, for which the surrounding Flatiron District is named...

-shaped plateau was named by early French explorers from New France

New France

New France was the area colonized by France in North America during a period beginning with the exploration of the Saint Lawrence River by Jacques Cartier in 1534 and ending with the cession of New France to Spain and Great Britain in 1763...

 (Quebec

Quebec

Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....

), Coteau meaning "slope" in French

French language

French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...

.

The plateau is composed of thick glacial

Glacier

A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...

 deposits, the remnants of many repeated glaciations, reaching a composite thickness of approximately 900 feet (275 m). They are underlain by a small ridge of resistant Cretaceous

Cretaceous

The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 shale

Shale

Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...

. During the last (Pleistocene

Pleistocene

The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

) Ice Age

Ice age

An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...

, two lobes of the glacier appear to have parted around the pre-existing plateau and further deepened the lowlands flanking the plateau.

The plateau has numerous small glacial lakes and is drained by the Big Sioux River

Big Sioux River

The Big Sioux River is a tributary of the Missouri River, long, in eastern South Dakota and northwestern Iowa in the United States. The United States Board on Geographic Names settled on "Big Sioux River" as the stream's name in 1961....

 in South Dakota and the Cottonwood River

Cottonwood River (Minnesota)

The Cottonwood River is a tributary of the Minnesota River, 152 miles long, in southwestern Minnesota in the United States. Via the Minnesota River, it is part of the watershed of the Mississippi River, draining an area of in an agricultural region...

 in Minnesota. Pipestone

Catlinite

Catlinite is a type of argillite , usually brownish-red in color, which occurs in a matrix of Sioux quartzite. Because it is fine-grained and easily worked, it is prized by Native Americans for use in making sacred pipes such as calumets and chanunpas...

 deposits on the plateau have been quarried for hundreds of years by Native Americans

Native Americans in the United States

Native Americans in the United States are the indigenous peoples in North America within the boundaries of the present-day continental United States, parts of Alaska, and the island state of Hawaii. They are composed of numerous, distinct tribes, states, and ethnic groups, many of which survive as...

, who use the prized, brownish-red mineral to make their sacred peace pipes. The quarries are located at Pipestone National Monument

Pipestone National Monument

Pipestone National Monument is located in southwestern Minnesota, just north of the city of Pipestone, Minnesota. It is located along the highways of U.S. Route 75, Minnesota State Highway 23 and Minnesota State Highway 30....

 in the southwest corner of Minnesota

Minnesota

Minnesota is a U.S. state located in the Midwestern United States. The twelfth largest state of the U.S., it is the twenty-first most populous, with 5.3 million residents. Minnesota was carved out of the eastern half of the Minnesota Territory and admitted to the Union as the thirty-second state...

 and in adjacent Minnehaha County, South Dakota

Minnehaha County, South Dakota

As of the census of 2000, there were 148,281 people, 57,996 households, and 37,581 families residing in the county. The population density was 183 people per square mile . There were 60,237 housing units at an average density of 74 per square mile...

.

Numerous wind farms have been built on the area to take advantage of the high average wind speeds.

External links

• USGS Site on the Coteau des Prairies
• Glacial History of Coteau des Prairies (University of South Dakota
  University of South Dakota
  The University of South Dakota ', the state’s oldest university, was founded in 1862 and classes began in 1882. Located in Vermillion, South Dakota, United States, USD is home to South Dakota's only medical school and law school. USD is governed by the South Dakota Board of Regents, and its current...
  
  ).