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The vast central area of the U.S., into Canada, is a landscape of low, flat to rolling terrain in the Interior Plains. Most ot its eastern 2/3rds forms the Interior Lowlands, discussed on this page. The Lowlands gradually rises westward, from a line passing through eastern Kansas, up to 5000+ feet in the unit known as the Great Plains (next page). Much of the Plains are now converted land use-wise to farming.

The Interior Lowlands:

Cleveland, Ohio, Chicago, Illinois and the Midwest

Proceeding westward, the Appalachian Plateau topography gradually gives way to gentle rolling hills and then (in central Ohio) to flat lands converted principally to farms and urban areas. This is the beginning of the vast Interior Plains of North America, shown first as a single-colored geographic pattern and then in a detailed map which names its subdivisions:

The Interior Plains, in orange-red.

Regions of the Interior Plains.

The Interior Plains are nearly coincident with the vast Mississippi River Drainage System (other major components are the Missouri and Ohio Rivers), as seen in this map. These rivers have for tens of millions of years been eroding downward into the mostly horizontal sedimentary rocks of Paleozoic, Mesozoic, and Cenozoic ages. The modern Mississippi River system has developed during the Pleistocen Epoch of the Cenozoic Era.

The Mississippi River Drainage System.

The first image depicting Interior Lowlands landforms is just west of the transition between Appalachian-controlled topography and the Interior or Central Lowlands. The scene is that of Cleveland (blackish area on the shore), Lake Erie with partially melted ice in March of 1973, the widespread farmlands of northern Ohio and southern Ontario, and low hills and lakes (mostly from the last glacial retreat) near Akron.

Landsat MSS image of Lake Erie, Cleveland, northeast Ohio, and part of Ontario.

Cleveland, Ohio lies astride the southeasstern shores of Lake Erie. Here is the central city imaged at 4 meters by IKONOS on April 26, 2000:

IKONOS image of Cleveland, Ohio.

The land remains hilly between western Pennsylvania and just east of Columbia, Ohio. Thereafter, the land becomes much flatter. Here is Indianapolis, Indiana , the home of the Indy 500, as seen by Landsat in late Fall:

Landsat TM view of Indianapolis, IN on November 16, 2001.

Typical of the Interior Lowlands is the region around Chicago, Illinois, shown in this Landsat MSS scene.

 Landsat MSS image of northeast Illinois, including Chicago.

The underlying rock type in the Illinois part of the Interior Province is limestone, but nearly all of the surface here is controlled by glacial deposits. The rich soils from these materials promote farming, of which corn, soybeans, and oats make up the major crops. Most of fields in this scene are rectangular, and many now are fallow (tan-colored) after harvesting. Trees cluster along the banks of rivers such as the Illinois, Des Plaines, and Kankakee that stand out among the farms.

The Chicago Loop (named for the rectangular track layout of elevated trains) reaches to Lake Michigan in the dense central downtown which is visible as blue tones, while much of the surrounding metropolitan areas are expressed by the reds denoting trees in suburban settings. Look in the image for features near the waterfront and compare with those in these three aerial oblique photos of that area:

Panoramic view of the Chicago waterfront.
Courtesy: Carolina Map Distributors

Aerial oblique view of downtown Chicago and its waterfront.

View of downtown Chicago looking north.

Chicago sits along the southwest tip of Lake Michigan, one of the five Great Lakes. All of them originated as basins cut by glacial scouring and, in places, from damming by moraines. Gary, Indiana is the blue area at the southern tip of the Lake.

6-8: What time of the year was this image probably made? Near Gary, IN, note the wispy clouds extending north-northeast into the Lake; what might they be? ANSWER

Another major Great Lakes city lies almost due east of Chicago. Detroit, Michigan is built along the Detroit River which connects Lake Ontario at its northwest end with Lake St. Clair above a peninsula in Canada on which Windsor is situated across river from Detroit. Both cities are shown in this aerial view:

Detroit, MI on the left; Windsor, Ontario on the right, separated by the Detroit River.

These two Landsat subscenes shows part of this metropolitan complex; the second, Landsat-7 ETM+, presents a higher resolution version in natural color.

Landsat TM subscene covering part of Detroit and neighboring Windsor, Canada.

Landsat-7 ETM+ view of Greater Detroit.

Another area within the glaciated part of the Interior Lowlands is southern Minnesota. In the next scene, farmland with many glacial lakes is predominant. But, Minneapolis and St. Paul just to its east appear (blue patches near top center) along a part of the upper reaches of the Mississippi River (whose headwaters begin to the northwest) that make that mighty stream much narrower in this part of its course. The Minnesota River joins the Mississippi from the southwest; the St. Croix River to the east forms the border there with Wisconsin which then continues southward along the Mississippi.

Landsat MSS image of southern Minnesota, including Minneapolis-St. Paul

This is Minneapolis seen from the air:

Minneapolis, Minnesota.
Courtesy: Carolina Map Distributors

Wisconsin has two larger cities that one thinks of offhand: Madison and Milwaukee. But to represent this state the writer has selected a very remarkable small city of about 100000: Green Bay, which is the smallest city to support an NFL team, the Packers - perennial powerhouses that operate in an often frigid open stadium filled with dedicated and loud fans.

Landsat-7 subscene of Green Bay, Wisonsin.

South of the glacial boundaries, the Interior Lowlands is a mix of farmlands and forests, in flat to rolling hill country. This next scene in Tennessee is typical. Nashville, Country Music's capital, lies on the Cumberland River. To the southeast (lower right) is the edge of the Cumberland Plateau (assigned to the Appalachian province and equivalent to the Allegheny Plateau); its prominent west-facing scarp continues both southward and into Ohio east of Columbus. Nashville is near the edge of the Nashville Dome, a gentle upwarp of sedimentary rocks (mostly limestones); its broad outline is elliptical, and is indicated by forests (evident in the image) that selectively concentrate on soils from certain sedimentary units.

 Landsat MSS image of Nashville and surrounding countryside in Tennessee.

Most of the Mississippi River drainage passes through various parts of its vast drainage system within the Interior Plains. But the Lower Mississippi from southernmost Missouri southward is emplaced on a part of the Gulf Coastal Plains known as the Mississippi Embayment (an inflow of marine waters starting about 75 million years ago which deposited thick sediments in a structural trough). In this Landsat-1 view we see the state of Mississippi on the right and Louisiana on the left (along the west bank of the active river). Here, in the Greenville, MS area) the meandering Mississippi River has cut a floodplain about 80 km (50 miles) wide. The forested uplands bedrock to the right consists in part of Eocene sedimentary rocks covered by windblown glacial dust (loess).

The Mississippi River and its floodplain and uplands.

The states immediately west of the Mississippi River are considered part of the Interior Lowlands.

Not all of the Interior Plains is flat and low. Some high hills/low mountains occur. The broadest of these lies within southern Missouri and northern Arkansas and is known both as the Interior Highlands and Ozark Plateau. The Landsat scene below is mostly in Arkansas. The darker red area near the middle of the image is the Boston "Mountains", which are actually a dissected plateau of horizontal (mostly Pennsylvanian in age) strata, with relief up to 300 m (1000 ft).

The Arkansas section of the Interior Highlands.

Another state in the westernmost Interior Lowlands is Iowa, sometimes placed specifically in the Central Lowlands subprovince, shown in this Landsat TM mosaic:

The state of Iowa in a Landsat mosaic.

Most of the state is underlain by Paleozoic rocks (limestones common) covered by Pleistocene till deposits. The capital city is Des Moines, in the center of Iowa:

Landsat subscene of Des Moines, Iowa.

In the Southeast part of the state is Iowa City, home of the University of Iowa, as shown in this IKONOS image:

Iowa City, Iowa; the University is on the west side of the Iowa River.

During the 19th Century in that period when tens of thousands of Americans followed Horace Greeley's dictum "Go West, young man!", the jumping off places for Prairie Schooners to start their trek across the Great Plains were at the end of eastern rail lines at Kansas City and St. Joseph on the Missouri River at the west end of that state. Here is a space image of the Kansas City area:

Kansas City; towns by that name occur in both the states of Missouri and Kansas.

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Primary Author: Nicholas M. Short, Sr. email: