The work of John Bluemle PhD

Drainage

9-HOW THE MISSOURI RIVER FORMED

geology, North America glacial map

Fig. 9-A. Drainage map of central North America, east of the Mississippi River: Bell River drainage system. Diagram: 1-29-2015

Agreement on the origin of the name of the “Missouri” River is difficult because too many contradictory explanations exist. The name apparently comes from a Siouan Indian word, “ouemessourita” or “emissourita,” translated by early French explorers as “those who have wooden dugout canoes,” or “river of the large canoes,” or “town of the large canoes,” or any of several other possibilities. One source says the term was the name the Illinois Indians used for the native people who lived in the Mississippi River Valley, probably mainly on the eastern (Illinois) side of the river; another source says they lived in what is now the State of Missouri.

The Missouri River originates near Three Forks, Montana, where the Gallatin, Jefferson, and Madison rivers come together. It flows 2,341 miles to St. Louis, where it joins the Mississippi River. This makes the combined Missouri-Mississippi River, at 3,709 miles, the fourth longest river in the world, after the Nile, Amazon, and Yangtze. The entire length was once riverine environment but, due to the dams that have been built along its route, approximately a third of the length is now reservoirs – lake environment rather than river. Listed from upstream to downstream, the dams are: Fort Peck in Montana, Garrison in North Dakota, Oahe, Big Bend, and Fort Randall in South Dakota, and Gavins Point on the South Dakota-Nebraska border.

Along with its valley, the Missouri River is largely a product of glaciation. Before North America was glaciated, all the drainage in North and South Dakota, eastern Montana, and northern Minnesota was north or northeastward into Canada. There was no “Missouri River” carrying drainage from the northern mid-continent region to the Gulf of Mexico. The way I define the Missouri River requires that its water ultimately reach the Gulf of Mexico as it does today, and that it carry water draining from the Rocky Mountains and northern Great Plains. Prior to glaciation, no such river existed. Why is the situation today so different than it was before the Ice Age?

North Dakota, geology, glacial drainage

Fig. 9-B. Map of North Dakota showing the drainage pattern prior to glaciation. All rivers flowed north or northeast into Canada. The Missouri River Valley did not exist (except for short segments that correspond to portions of valleys such as the Knife and McLean River valleys (see text). Diagram. 1-29-2015

The modern Missouri River Valley in North Dakota consists of several discrete valley segments that differ markedly from one another. Some of the segments are broad: six to twelve miles wide from edge to edge, with gentle slopes from the adjacent upland to the valley floor. Others are narrow: less than two miles wide, with rugged valley sides – even badlands slopes in places. Most of the wide segments trend from west to east whereas the narrow segments are mainly north-south. The Bismarck-Mandan area is one of only a few exceptions, and I’ll explain why shortly.

The west-east segments of the Missouri River Valley are wide because they coincide with much older valleys that existed long before the area was glaciated. Old, mature river valleys, which formed over long periods of time (hundreds of thousands or millions of years), tend to be broad with gentle slopes. Younger valleys formed more quickly (tens of thousands of years), and are usually narrower with steeper sides. An example of a wide segment is the forty-mile-long, west-east segment of the Missouri River Valley upstream from Garrison Dam. This part of the valley, now flooded by Lake Sakakawea, was once the route of a river that flowed east to Riverdale. However, the river didn’t turn south at Riverdale, as it does today. Rather, it continued eastward past Riverdale, and on past Turtle Lake and Mercer, flowing into northeastern North Dakota. For convenience, I’ll refer to this ancient river as the “McLean River.”

McLean River, geology, North Dakota

Fig. 9-C. . Map showing a portion of the route of the preglacial “McLean River,” which flowed eastward through a broad valley that passed between Garrison and Riverdale, to the Turtle Lake area, and on into Sheridan County. When the McLean River valley was blocked by a glacier (to the east of the area shown on this map), a proglacial lake formed in the valley. When the lake overflowed southward from a point near Riverdale – at the site of the modern Garrison Dam – a narrow diversion trench was cut. The modern Missouri River flows through this diversion trench. Diagram: 1-29-2015.

East of U. S. Highway 83, the route of the old McLean River valley is a broad, low area, partly buried beneath tens to hundreds of feet of glacial sediment. Lake Audubon, Turtle Lake, Lake Brekken, Lake Holmes, Lake Williams, Lake Peterson, Pelican Lake, Blue Lake, Brush Lake, and other smaller lakes mark the former route of the McLean River through eastern McLean County. However, continuing farther east, the McLean River valley becomes so deeply buried beneath glacial deposits that it would be nearly impossible to know its route from a study of the surface topography. Fortunately, hundreds of test holes were drilled during studies of the ground water resources of the glacial deposits so we have a good idea of the route the river followed into northeastern North Dakota.

Another wide, west-east trending segment of the modern Missouri River Valley, between Stanton and Washburn, is an eastward continuation of the modern Knife River. Prior to glaciation, the Knife River flowed east in its modern valley to Stanton, but it continued eastward from there, past Washburn. A few miles east of Washburn it turned slightly northeastward. The ancient Knife River joined the McLean River near the town of Mercer and the combined Knife-McLean River continued northeastward to the Devils Lake area. It then flowed north along the east side of Turtle Mountain area into Canada.

Still another wide segment of the Missouri River Valley in northwestern North Dakota extends from near the modern Missouri River /Yellowstone River confluence, northeastward to Williston.

Fig. 9-D. Map showing the Missouri River Valley at Bismarck-Mandan. South of Bismarck (south of the railroad), the valley is wide because it corresponds to the old, northeast-trending preglacial valley of the Heart River. North of the city, the valley is narrow with quite steep sides. This part of the valley was formed when an ice-dammed lake to the north, in the preglacial Knife River valley, overflowed from a point near Wilton. A similar ice-dammed lake existed in the Heart River valley east of Bismarck – the glacial Lake McKenzie. Diagram: 1-29-2015.

Fig. 9-D. Map showing the Missouri River Valley at Bismarck-Mandan. South of Bismarck (south of the railroad), the valley is wide because it corresponds to the old, northeast-trending preglacial valley of the Heart River. North of the city, the valley is narrow with quite steep sides. This part of the valley was formed when an ice-dammed lake to the north, in the preglacial Knife River valley, overflowed from a point near Wilton. A similar ice-dammed lake existed in the Heart River valley east of Bismarck – the glacial Lake McKenzie. Diagram: 1-29-2015.

This six-to-eight-mile-wide section of the valley coincides with the pre-glacial route of the Yellowstone River through that area. Prior to glaciation, the Yellowstone River continued to the north, past Williston, following a route that is now mainly buried. The pre-glacial route coincides with the modern route of the Little Muddy River as far as Zahl, about 30 miles north of Williston. North of Zahl, the old Yellowstone River valley into Canada is so deeply buried that its route is known only through drill-hole data. The river entered Saskatchewan about six miles north of Crosby.

The Missouri River Valley between Williston and New Town, now flooded by Lake Sakakawea, follows the same route as did an east-flowing, mid-Ice Age — but probably not pre-glacial – river. This part of the Missouri River Valley is somewhat narrower than most other east-west segments of the valley in North Dakota, and it is also younger than most of them. It is a continuation of a mid-Ice Age river that flowed east from Montana. In Montana, the route of this river coincides with the modern route of the Missouri River past Wolf Point, Poplar, and Culbertson. The Montana segment of the mid-Ice Age river joined the north-flowing Yellowstone River near Buford.

At Bismarck-Mandan, the Missouri River Valley is about two miles wide at the Interstate Highway 94 crossing, but on the south side of Bismarck the valley broadens to six miles wide. The widening southward seems contrary to my earlier comment that north-south segments of the valley tend to be narrow. There is a reason for this exception though. The valley widens at Bismarck-Mandan because, prior to glaciation, the Heart and Little Heart rivers, which today flow into the Missouri River, joined a few miles east of Bismarck. The combined (preglacial) Heart/Little Heart River continued flowing eastward, joining the Cannonball River in southern Burleigh County, near Moffit. The old, combined Heart/Little Heart valley still exists as a broad lowland south and southeast of Bismarck. It is now a wide spot in the Missouri River Valley.

The Heart/Little Heart river system was probably dammed several times by glacial ice advancing westward. Each time a glacier advanced, a lake formed ahead of – west of – it in the Heart/Little Heart valley. The lake (or lakes) are referred to as glacial Lake McKenzie. At least once, and possibly several times, glacial Lake McKenzie overflowed, carving what is now the Missouri River valley south of the Bismarck-Mandan area.

Missouri River, Fort Lincoln

Fig. 9-E. Photo of the Missouri River at Fort Lincoln State Park south of Mandan. The river is shown in flood stage in August of 2011.Photo: 8-21-2014.

When the (preglacial?) Heart River flowed eastward, through the Bismarck area, it deposited a thick gravel deposit which now lies buried about 100 feet beneath the Missouri River. Bismarck’s new (2013) water-intake structure withdraws ground water from this old Heart River gravel deposit.

When the McLean River valley was blocked by a glacier in the Riverdale area midway through the Ice Age, a large proglacial lake formed ahead (to the west) of the ice in the valley. This lake might be considered to be the “original” Lake Sakakawea: an early ice-dammed lake that predated the Corps of Engineers version of Lake Sakakawea by thousands of years. When the lake overflowed, near where Garrison Dam is today, the resulting flood quickly carved a narrow spillway trench south to the Stanton area.

Similarly, the Knife River, which flowed past Stanton and on to the Washburn area, was dammed by glacial ice just east of Washburn and the valley was flooded upstream beyond Washburn. The resulting lake overflowed and spilled southward into the Burnt Creek-Square Butte Creek drainage, carving a narrow trench from a few miles east of Washburn to the Bismarck-Mandan area. The modern Missouri River flows in that trench today.

And, as I noted, when the Heart/Little Heart River was dammed by a glacier, which probably advanced as far west as Sterling, glacial Lake McKenzie formed. The lake overflowed southward, forming a new valley, now flooded by the northernmost part of Lake Oahe.

The youngest and narrowest segment of the Missouri River Valley in North Dakota is at New Town, between Four Bears Bridge and Van Hook Bay. As recently as 13,000 years ago, a glacier blocked the Missouri River from its route around the north and east side of New Town. The old river route (prior to 13,000 years ago) is now a broad valley, known as the “Van Hook Arm,” flooded by Lake Sakakawea. The glacier dammed the valley, causing a lake to form upstream (to the west) of the point of blockage. Thick layers of lake sediment, known as the “Crow-Flies-High silt,” were deposited in the ice-dammed “Crow-Flies-High Lake.” Crow-Flies-High Lake extended westward from the New Town area to near Williston. In many places between these two cities, exposures of the bedded lake silt deposits occur at elevations as high as 70 feet above the modern, maximum reservoir level (1850 feet) of Lake Sakakawea. The lake rose until it overflowed southward, cutting the channel now spanned by the Four Bears Bridge.

Other “Missouri” River Routes

Up to now, I’ve tried to explain the origin of the modern route of the Missouri River. That’s not the end of the story though. The modern route of the Missouri River is only the most recent of many routes that earlier “Missouri” rivers followed through North Dakota at various times during the Ice Age. These rivers also carried runoff water from as far away as the Rocky Mountains, through North Dakota, on its way to the Gulf of Mexico. However, most of these routes, mainly in northern and eastern North Dakota, are now buried beneath thick accumulations of glacial sediment. Whatever routes these rivers followed, they had to have flowed generally eastward and southward because their original, northerly and northeasterly routes into Canada were blocked by ice each time glaciers advanced into the state. Test drilling, done to study ground water resources, has helped us identify least least some parts of the old “Missouri” River routes. There are dozens of them.

North Dakota, geology, ancestral Missouri River

Fig. 9-F.Map showing the old route of the Missouri River at New Town (within the dashed lines) and the more recent route, formed when a glacier diverted the river farther southwest (within the solid lines). This diverted loop of the Missouri River is the youngest portion of its valley through North Dakota. It formed about 14,000 years ago. Diagram 1-29-2015

One of several early routes of the Missouri River, determined by test-hole drilling, took the river southward past Cooperstown and Valley City to the southeastern corner of the state. Another route took the river southeastward past Jamestown. In the northern part of the state, rivers like the Yellowstone were diverted from their northerly routes to easterly and southeasterly routes, past places like Columbus, Kenmare, and Minot. These buried valleys can be considered to be early “Missouri” River routes.  The array of buried river valleys is really amazing – and so complicated – and such a great number of possible routes exist, that it is impossible to work them all out. All of them are now buried beneath hundreds of feet of glacier sediment, and most of them have no surface evidence whatsoever.

However, not all of the early “Missouri River” routes through North Dakota are deeply buried. In the western part of the state, a version of a Missouri River formed when an early glacier advanced at least as far southwest as the Hebron area. The margin of that glacier coincided with what is now a prominent, broad valley, known as the Killdeer-Shields channel. The channel extends southeastward from the Killdeer Mountains, past Hebron and Glen Ullin, to the Fort Yates area, crossing the modern Missouri River Valley, and continuing through southwestern Emmons County into South Dakota. No river flows through the Killdeer-Shields channel today, but an early Missouri River flowed in it, perhaps for a longer period of time than the current Missouri River has flowed in its modern route. Interstate Highway 94 crosses the valley about half way between Dickinson and Mandan. Good views of the Killdeer-Shields channel can be seen just north of Richardton and between Hebron and Glen Ullin. Old U.S. Highway 10 and the Burlington Northern Santa Fe Railroad follow the old channel from Hebron to Glen Ullin.

Summary

I realize that my description of the changes in the routes the various “Missouri” Rivers have followed since the Ice Age began is complicated. Even so, it doesn’t begin to account for the evolution of all of the changes in the vast array of routes that rivers followed during the Ice Age in North Dakota.

Most of the narrow, north-south segments of the modern Missouri River Valley correspond to places where glaciers diverted then-existing rivers southward. Glaciers in the central part of the state diverted northeast-flowing rivers, like the Knife, McLean, and Heart-Little Heart, and Cannonball, forcing them to flow southward from the points of diversion, forming the north-south segments of the modern Missouri River. Glaciers advancing into northwestern North Dakota diverted mainly north-flowing rivers, like the Yellowstone and Little Missouri, away from their routes into Canada, forcing them to flow to the east and south.

The modern Missouri River Valley is a “composite” feature, consisting of older, wide pre-glacial segments, formed over long periods of time prior to the Ice Age, along with younger, narrow segments that were cut relatively quickly at various times during the Ice Age. The parts of the Missouri River Valley that extend mainly from west to east are wider and much older than are the narrower segments that extend from north to south. Many of the early “Missouri” River routes followed for varying periods of time during the Ice Age in northern and eastern North Dakota were later buried beneath thick deposits of glacial sediment.

The current route of the modern Missouri River Valley is only the latest in a continuing series. After the next glacier has come and gone, a new version of the Missouri River will likely follow a different route than does the river today.

Lake Sakakawea; New Town; Four Bears bridge; ND geology;

Fig. 9-G. Photo of the Missouri River from Crow-Flies Hill at New town, Mountrail County. Lake Sakakawea floods a narrow, north-south valley that was cut when the Missouri River was diverted southward from its earlier route around the north side of New Town. Photo: 7 -16-2010

7-THE BADLANDS – PART ONE

If asked what he or she knows about North Dakota’s geology, an average resident will likely mention the badlands first. That’s true too of visitors, many of whom come to the state to see our best-known natural feature, the scenic badlands along the Little Missouri River.

Little Missouri River

Fig. 7-A. View upstream (to the south) of the Little Missouri River in Billings and Golden Valley counties about three miles north of Bullion Butte. Photo: 7-8-2010.

The badlands landscape is a rugged and hilly one, best viewed from above, looking down on the hills, not up at them, as we usually view buttes. From the rim of the “breaks,” the point where we descend into the badlands, an intricately eroded landscape of sparsely wooded ridges, bluffs, buttes, and pinnacles lies before us. Black veins of lignite coal may be seen eroding out of the steep badlands slopes. Reddish bands of clinker add vivid colors to the area. Pieces of petrified wood, as well as fossil stumps and logs, litter the surface. Behind us stretch rolling plains, interrupted only by occasional buttes.

Bullion Creek Badlands, Golden Valley County

Fig. 7-B. Bullion Creek Formation badlands, four miles north of Bullion Butte in Golden Valley County. Castellated sandstone structures, resulting in towering or battlement shapes, can be seen at the top of the butte. Such structures are examples of one of many kinds of badlands erosion. Photo: 8-7-2011.

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The American Indians, who inhabited the area when the European settlers arrived, referred to badlands as “mako sica,” (“land bad”). Early French explorers translated and added to this, referring to “les mauvais terrers a’ traverser” (“bad land to travel across”).

Bullion Creek badlands, Billings County

Fig. 7-C. Tertiary Bullion Creek Formation badlands along the Little Missouri River, Billings County. This view is to the north, along the East River Road about five miles north of the South Unit of Theodore Roosevelt National Park. The snow shows the erosion patterns in the south-facing bluffs in the distance beyond the river, which is at the base of the bluffs. Photo :1-15-2010.

 

 

 

 

General Alfred Sully, preparing to cross the badlands in August of 1864, described them as “hell with the fires burned out.” Theodore Roosevelt, who lived for a while in the Little Missouri Badlands in the 1880s, described them as “fantastically beautiful.” I prefer TR’s description.

Age of the Badlands Materials

Badlands topography is found in several places on the plains of the U.S. and Canada. The best-known badlands in the United States are the extensive “Big Badlands,” along the White River in western South Dakota. Near Dickinson we have the “South Heart Badlands” (known also as the “Little Badlands”) where we find layers of sedimentary rock, equivalent (same materials, same geologic age) in part to those in South Dakota’s Big Badlands. The South Heart Badlands are an erosional remnant of what was once a large butte or group of buttes. The South Heart Badlands are carved mainly from strata of Eocene and Oligocene age, ranging between 55 and 25 million years old. The youngest beds belong to the Miocene Arikaree Formation sandstone (22 million years old), which caps some badlands buttes.

South Heart Badlands

Fig. 7-D. South Heart Badlands about six miles south of South Heart, Stark County. Photo 9-24-2009..

North Dakota’s Little Missouri Badlands extend from near the Little Missouri River’s headwaters in Wyoming near Devils Tower to the point where the Little Missouri River joins the Missouri River in western North Dakota. The materials being eroded in these, our most extensive area of badlands, are much older than those in the South Heart Badlands.

The oldest materials in the badlands are in the southwest corner of the state, near Marmarth, where Cretaceous-age Hell Creek Formation beds (about 65 million years old) have been carved into badlands. The dark and somber, gray and purple beds of the Hell Creek Formation contain dinosaur fossils. Small patches of badlands, carved from the Hell Creek formation can also be seen along State Highway 1806 between Huff and Fort Rice in Morton County.

badlands

Fig. 7-E. This badlands topography is located about three miles northeast of Marmarth in Slope County. The materials are Cretaceous in age, about 65 million years old. In contrast to the badlands farther north, which are shades of light brown, these older beds are darker, tending to be purple and gray. They contain dinosaur fossils. Photo 10-22-2009.

However, the main area of  the Little Missouri Badlands is that which has been carved largely from the Paleocene Bullion Creek and Sentinel Butte formations, which were deposited  between 58 and 56 million years ago. The beds that have been eroded into these badlands are too young for dinosaur fossils; the dinosaurs were already extinct when they were deposited.

Between 70 and 40 million years ago, a major mountain-building event known as the Laramide Orogeny (orogeny = “mountain forming”) formed the Rocky Mountains in Montana and Wyoming. As the mountains rose, they were attacked by intense erosion, providing sediment to eastward-flowing rivers and streams. The rivers delivered the eroded sediment to western North Dakota’s coastal plain, an area that could be likened to today’s Mississippi River Delta (central North Dakota was an inland sea at that time). Sediment from the eroding mountains accumulated into thick layers of soft, poorly lithified siltstone, claystone, and sandstone: materials that were deposited on river floodplains and in swamps in what is now western North Dakota. These are the sediments we see exposed today in the Little Missouri Badlands.

In addition to the stream-transported sediments, clouds of volcanic ash, blown eastward from the rising Rocky Mountains during the Laramide Orogeny, collected in layers that were later weathered to clays ( “bentonite”). When wet, the clay absorbs water and swells, and it can become slippery when wet so don’t try walking or driving on it. When the beds dry, they assume a surface  texture, similar in appearance and consistency to popcorn, with colors ranging from white to bluish-gray or black.

Why the Badlands Formed

South Heart Badlands

Fig. 7-F. The dark-gray to black mound-like hills are examples of topography of the South Heart Member of the Eocene Chadron Formation in the South Heart Badlands south of the town of South Heart, Stark County. The material is a clay that forms a popcorn-like surface when it is dry. When wet, it is sticky and slippery. The clay is a weathering product of volcanic ash. Photo 9-24-2009

Even though the layers of sedimentary rock exposed in North Dakota’s Little Missouri Badlands range from Cretaceous through Eocene in age (65 to 50 million years old), the badlands themselves–the hills and valleys we see today–are not nearly that old. Before a glacier diverted it, the Little Missouri River flowed northward through a broad, smooth valley, joining the early Yellowstone River in northern Williams County. The Little Missouri and Yellowstone rivers came together near Alamo (about 30 miles north of Williston) in a place now buried beneath 400 feet of glacial deposits. From there, the combined Yellowstone-Little Missouri River flowed northeastward into Canada.

The diversion of the Little Missouri River, away from its route to the north, probably happened sometime prior to the deposition of a volcanic ash bed on the glacial sediment blocking the channel (the ash was deposited as a result of a volcanic eruption in the area of Yellowstone Park 640,000 years ago). It is possible, though, that an earlier glacier might have diverted the river – the 640,000-year figure is a minimum date; erosion of the badlands may have begun as early as 3.5 million years ago.

Since it was diverted by glacial ice, the Little Missouri River has flowed over a shorter and steeper route than it did prior to its diversion. That part of the river’s route today, from the point where it makes its sharp turn toward the east in the area of the North Unit of Theodore Roosevelt National Park, is east rather than north as it had been before a glacier diverted it. When the river assumed its new, shorter route toward the Gulf of Mexico, it began a vigorous erosion cycle, cutting down more rapidly and deeply and sculpting badlands topography. The badlands then, are an indirect result of glacial activity, even though the only conspicuous direct evidence of glaciation remaining in the area is an occasional glacial erratic on the upland in northern McKenzie County.

Sentinel Butte badlands; Theodore Roosevelt Park

Fig. 7-G. Badlands carved from the Tertiary-age Sentinel Butte Formation in the North Unit of Theodore Roosevelt National Park. Notice that certain beds can be followed across the entire vista, although they may be discontinuous, eroded away in places. An example is the bluish gray layer that forms the surface of many table-like pedestals. This layer is a bentonitic clay, a weathered volcanic ash deposit. The layers shown here are slightly younger than are those exposed in the South Unit of the park. Total relief here, from valley floor to upland surface, is about 500 feet. Photo: 10-24-2009

 

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