• Saying a better geomorphology paradigm is needed is easy, developing a better geomorphology paradigm according to the rules of science is much more challenging. While the existing geomorphology (and geology) paradigm is unproductive in terms of determining erosional landform origins, researchers have used the paradigm to construct significant frameworks of ideas related to other types of geology and geomorphology evidence. Any fundamentally new geomorphology paradigm is going to challenge those existing and well established ideas and is not going to be automatically accepted. In fact any fundamentally new geomorphology paradigm to even be seriously considered will have to demonstrate its ability to explain vast quantities of previously unexplainable geomorphology evidence. The Missouri River drainage basin landform origins research project is such a demonstration. The project is introducing a fundamentally different and new geomorphology paradigm to the geomorphology research community by systematically going around the Missouri River drainage basin and interpreting the origins of large numbers of previously unexplainable landform features. Geomorphology research community reviewers not only need to check to make sure the rules of science have been followed, but also need to evaluate the new paradigm by comparing it with the existing paradigm in terms of each paradigm’s abilities to explain unexplained evidence.

The Missouri River drainage basin landform origins research project paradigm

• The new geomorphology paradigm being introduced by the Missouri River drainage basin landform origins research project is here named the “thick ice sheet that melted fast” paradigm. The paradigm name identifies two major differences from the existing paradigm, specifically the new paradigm requires one thick ice sheet, not multiple thin ice sheets as the existing paradigm implies. Further the new paradigm requires rapid ice sheet melting and immense melt water floods, while the existing paradigm implies much more gradual ice sheet melting with much smaller melt water floods. However, there are many other important differences. Among those differences are the following:

• Differences between the new paradigm and the existing paradigm are significant and the new paradigm challenges many well established geology and geomorphology ideas. The existing geology and geomorphology paradigm has been fleshed out by thousands of researchers over a period of many decades. The “thick ice sheet that melted fast” paradigm to date has been developed by a single researcher, who has worked on the problem for approximately thirty years. The Missouri River drainage basin landform origins research project essays demonstrate how the new paradigm can explain vast quantities of previously unexplainable topographic map evidence. However, like any new paradigm being introduced for the first time, the explanations are not perfect and can probably be significantly improved. Further, this demonstration of how the new paradigm explains topographic map evidence is only a beginning. Much more evidence needs to be explained, and as that additional evidence is explained the new paradigm will be further fleshed out.

East-West Continental Divide origin

• Perhaps the best way to illustrate differences between the new paradigm and the existing paradigm is to describe how the new paradigm explains the east-west continental divide origin in Montana, Wyoming, and Colorado. Today the Montana, Wyoming, and Colorado east-west continental divide is often located along the crests of high Rocky Mountain ranges, although there are places where the continental divide crosses deep mountain passes and other places where the continental divide crosses high intermontane basin areas. As already noted the existing geology (and geomorphology) paradigm implies the Rocky Mountains existed prior to any large Cenozoic ice sheets (in North America at least), which implies the continental divide and major drainage basins, both east and west of the continental divide, had already been formed before ice sheets covered large regions of northern North America. While correlations between Rocky Mountain alpine glaciation and continental glaciation are debated, the existing paradigm implies the two glaciations are in some way related and occurred at about the same time. Further, Rocky Mountain alpine glaciation is often cited as a major erosion agent responsible for carving deep valleys eroded into resistant Rocky Mountain bedrock while advocates of the same paradigm suggest continental ice sheets daintily tip-toed across pre-glacial valleys located in easily eroded northern plains bedrock. Finally there is no agreement as to when, how, or why the Rocky Mountains were uplifted or as to how, why, or when the east-west continental divide was formed.

• The “thick ice sheet that melted fast” geomorphology paradigm on the other hand requires a North American ice sheet which was several kilometers thick and which was located in a deep “hole”. This thick ice sheet was comparable in size, if not larger, to the modern-day Antarctic Ice Sheet and had been formed on a topographic surface which no longer exists, although there is excellent evidence massive melt water floods flowed across what are now high level Rocky Mountain erosion surfaces. In other words, the Rocky Mountains did not stand high above the topographic surface on which the thick ice sheet was formed. Through a combination of deep glacial erosion and crustal warping the ice sheet created a deep “hole” in which the ice sheet was located. The crustal warping included down warping (under the ice sheet) and uplift of mountain ranges and high plateau areas located beyond the ice sheet margins. Crustal warping was not instantaneous and immense melt water floods flowed from the thick ice sheet in whatever directions the topography at that time permitted, although crustal warping raised continent margins, forcing most melt water to flow in south directions. While melt water floods flowed along many routes one of the major south and southeast oriented flood flow routes roughly followed the present day east-west continental divide location. At that time there were no Rocky Mountains and immense south and southeast oriented melt water floods flowed along this route, which is named here the “Great Divide River”. The “Great Divide River” was only one of many south-oriented flood flow routes and more accurately was probably a complex of anastomosing southeast and south-oriented flood flow channels extending across what is now the entire Rocky Mountain region. How far south the “Great Divide River” melt water floods reached has yet to be determined, although the Rio Grande River valley in Texas, New Mexico, and Colorado probably was eroded headward along “Great Divide River” flood flow routes.

Great Divide River dismemberment from the east and west

• The “Great Divide River” was dismembered as headward erosion of deep valleys from both east and west captured the southeast and south oriented flood water. Also aiding in the dismemberment process was uplift of the Rocky Mountain region and adjacent high plateau areas. “Great Divide River” dismemberment began in the south and progressed northward. While outside the Missouri River drainage basin, and not addressed by Missouri River drainage basin landform origins research project essays, topographic map evidence demonstrates the Rio Grande River valley and its major tributary valleys (e.g. Pecos River valley) eroded headward across and along south and southeast-oriented “Great Divide River” flood flow routes. At the same time southeast-oriented Texas river valleys (such as the Colorado and Brazos River valleys) eroded headward from the Gulf of Mexico across and along south-oriented melt water flood flow routes east of the “Great Divide River” route. Headward erosion of the Mississippi River-Red River valley next captured south-oriented melt water flood flow east of the “Great Divide River” routes. Next the Mississippi River-Arkansas River-Canadian River valley eroded headward across south-oriented flood flow to capture large volumes of south-oriented flood flow from the “Great Divide River” eastern edge. South-oriented flood flow to the actively eroding Canadian River valley was subsequently beheaded by Arkansas River valley headward erosion, which also beheaded eastern flood flow routes to the actively eroding Rio Grande River valley.

• At about the same time headward erosion of the southwest-oriented Colorado River valley and its tributary valleys (from the Gulf of California) was beheading western “Great Divide River” flood flow routes to the actively eroding south and southeast-oriented Rio Grande River valley. Also, as the deep southeast-oriented Arkansas River and southwest-oriented Colorado River valleys were eroding headward into the Rocky Mountain region, the Missouri River-Kansas River (Smoky Hill River and Republican River) valleys and later the South Platte River valley eroded headward into the region to behead south oriented “Great Divide River” flood flow routes to the actively eroding Arkansas River valley. Colorado River valley headward erosion next beheaded south oriented flood flow routes to the actively eroding South Platte River valley. As these river valleys were eroding headward into the present day Rocky Mountain region to capture the massive south oriented “Great Divide River” melt water flood flow, the entire region was being uplifted and the Rocky Mountains began to emerge. Dismemberment of the “Great Divide River” from the east continued with headward erosion of the southeast-oriented North Platte River valley into central Wyoming. Headward erosion of this deep valley beheaded south- and southeast-oriented flood flow routes moving flood waters to the newly eroded Colorado River valley. Flood waters on the north and northwest end of one major flood flow route reversed flow direction to create the northwest and north-oriented North Platte River headwaters valley. Rocky Mountain uplift aided this massive flood flow reversal. West of the newly formed northwest and southeast-oriented North Platte River drainage route the massive south-oriented “Great Divide River” flood flow continued to move across the Great Divide Basin to actively eroding south-oriented Colorado River tributary valleys.

Great Divide River dismemberment from the ice sheet created deep “hole”

• North of the newly eroded southeast-oriented North Platte River valley headward erosion of deep east and northeast oriented valleys from the deep “hole” the decaying ice sheet had been located in was capturing south and southeast-oriented flood flow moving to the newly eroded North Platte River valley. Initially these deep east and northeast oriented valleys eroded headward from giant south-oriented ice-walled and ice-floored (later bedrock-floored) canyons carved into the rapidly melting North American ice sheet. The northeast and east-facing Missouri Escarpment is what remains of the one of these giant canyon’s southwest and west wall. Similar escarpments found throughout the northern plains region provide further evidence of these ice-walled and bedrock-floored canyons, which sliced the decaying ice sheet up into many smaller ice sheets and ice masses. The south-southeast oriented Missouri River valley along the present day Nebraska-Iowa border was eroded headward along the south-oriented flood flow emerging from the mouths of giant ice-walled canyons located at that time in southeast South Dakota. Due to Missouri River valley headward erosion the floor of the giant ice-walled canyon located east and northeast of the Missouri Escarpment (named here the “Midcontinent Trench”) was lower in elevation than the non glaciated surface along the ice sheet’s southwest margin. Southeast-oriented ice marginal floods then breached the detached ice sheet margin and flowed onto the ice-walled canyon floor. These breaches enabled deep east-oriented valleys to erode headward across the southeast-oriented ice-marginal floods and divert the flood water in an east direction to the much deeper ice-walled canyon floor. A deep east-oriented White River valley eroded headward from such a breach. Today that deep east-oriented White River valley’s south wall is the north-oriented Pine Ridge Escarpment and the valley’s north wall was removed by flood flow erosion and no longer exists.

• The giant ice-walled and bedrock-floored canyons being carved into the decaying ice sheet’s surface not only chopped the ice sheet up into a series of smaller ice sheets, but also opened up new and shorter melt water flood flow routes to adjacent ocean basins. The giant southeast and south-oriented melt water river flowing on the “Midcontinent Trench” floor (named here the “Midcontinent River”) was systematically captured and dismembered as new and steeper gradient flood flow routes opened up. First the “Midcontinent River” was captured in southeast North Dakota and diverted north and east to the Gulf of Saint Lawrence. Later the “Midcontinent River” was captured in north central North Dakota and diverted north and then east along what is now an east-oriented Assiniboine River valley segment. Next the “Midcontinent River” was diverted in an east direction along the east-oriented Qu’Appele River valley alignment. Still later the “Midcontinent River” was diverted in a northeast direction along the Saskatchewan River alignment to what is now Hudson Bay. As this dismemberment process took place deep valleys eroding headward from breaches in the detached ice sheet southwest margin became oriented in northeast and north directions. Headward erosion of the deep Cheyenne River valley beheaded southeast oriented flood flow to the newly eroded White River valley and eroded headward into eastern Wyoming where southeast oriented flood flow to the North Platte River valley was beheaded. Additional northeast and north-oriented valleys were then eroded across the southeast oriented ice marginal flood flow in sequence including the Moreau, Grand, Cannonball, Heart, Knife, Little Missouri, and Yellowstone River valleys. The northeast-oriented Yellowstone River valley and its northeast-oriented tributary (e.g. Powder and Tongue River) valleys were especially successful in capturing southeast and south-oriented ice marginal flood flow and they eroded headward in the “Great Divide River” flood flow route area.

• Another significant “Great Divide River” flood flow reversal and flood flow capture occurred when headward erosion of the deep northeast-oriented Yellowstone River valley beheaded and reversed south oriented flood flow routes moving through the present day Bighorn Basin and then to the newly eroded North Platte River valley in central Wyoming. One of these flood flow routes was located along the alignment of the present day Wind River Canyon, which at that time was being eroded into what were then the emerging Owl Creek Mountains. That flood flow reversal created the north-oriented Bighorn River located north of Wind River and the north-oriented Wind River route through Wind River Canyon. The flood flow reversal also captured a major southeast oriented “Great Divide River” flood flow route located between what were then the emerging Wind River Mountains and the emerging Owl Creek and Absaroka Mountains. This major flood flow capture created the present day southeast and north-oriented Wind River route to and through Wind River Canyon and beheaded all “Great Divide River” flood flow routes to the newly formed North Platte River drainage basin. Shortly before the Wind River capture event Sweetwater River valley headward erosion from the newly eroded North Platte River valley beheaded south oriented “Great Divide River” flood flow routes moving flood waters across the present day Great Divide Basin to what were then actively eroding south oriented Colorado River tributary valleys. Yellowstone River valley headward erosion continued and ultimately beheaded and reversed south and southeast oriented “Great Divide River” flood flow routes flowing across the Yellowstone Plateau. The resulting flood flow reversals created northwest and north-oriented Yellowstone River headwaters.

• North of the actively eroding Yellowstone River valley additional north and northeast oriented valleys eroded headward from another deep ice sheet margin breach located in the Montana northeast and North Dakota northwest corners. The northeast oriented Redwater River and the Missouri-Musselshell River valleys eroded headward from this major ice sheet margin breach and beheaded southeast and south-oriented flood flow routes to the newly eroded Yellowstone River valley. East-oriented valleys eroded headward from the newly eroded Missouri River-Musselshell River valley on both sides of what were then emerging Little Rocky Mountains and Bear Paw Mountains. The southern valley (now the Missouri River route) beheaded and reversed southeast-oriented flood flow moving to the newly eroded Musselshell River valley. The northern valley (now the Milk River valley) captured significant southeast-oriented ice marginal flow from the northwest and west and beheaded and reversed flood flow routes to the newly eroded Missouri River valley. These valleys probably eroded headward as channels in what was then a giant east and northeast oriented anastomosing channel complex with the emerging Rocky Mountain outliers located between the flood flow channels. Headward erosion of a deep northeast-oriented valley segment from what were then the interconnected and newly eroded east-oriented Missouri River and Milk River valleys beheaded and reversed a major southeast-oriented “Great Divide River” flood flow route west of the emerging Big Belt Mountains and created what is today the northwest-oriented Missouri River valley segment located in that region. The resulting flood flow reversal also created the north-oriented Gallatin and Madison River valleys, which had originated as south-oriented “Great Divide River” flood flows to and across the Yellowstone Plateau.

Columbia River valley and tributary valleys behead Great Divide River flood flow

• The Jefferson River-Beaverhead River valley then eroded headward and beheaded and reversed additional major southeast-oriented “Great Divide River” flood flow routes. Perhaps the most obvious of the beheaded flood flow routes was along the alignment of the present day Clarks Fork valley (northwest of Butte, Montana) and then continued (probably as an anastomosing complex of channels) in a south, southeast, and east direction to the Yellowstone Plateau. The resulting flood flow reversal created the west and northwest-oriented Red Rock River. The northwest, north, northeast, southeast, south, and northeast oriented Big Hole River valley was captured by Beaverhead River valley headward erosion and had initially eroded headward from the south oriented “Great Divide River” flood flow route beheaded by the Beaverhead River valley capture. At that time there were south and southeast-oriented “Great Divide River” flood flow routes west of the Beaverhead Mountains (located along the Idaho-Montana border). These south and southeast-oriented “Great Divide River” flood flow routes west of the Beaverhead Mountains were being beheaded and reversed by headward erosion of the west oriented Salmon River valley, which eroded headward from a newly beheaded and reversed north and northwest-oriented “Great Divide River” flood flow route, which is today a Snake River valley segment. The north and northwest-oriented Snake River valley segment was created when headward erosion of a west and southwest-oriented Snake River valley segment beheaded and reversed another south oriented “Great Divide River” flood flow route. The west and southwest-oriented Snake River valley segment eroded headward from the deep Columbia River valley, which eroded headward from the Pacific Ocean across additional south-oriented melt water flood flow routes further to the west. Subsequently Columbia River valley headward erosion beheaded and reversed the southeast-oriented “Great Divide River” flood flow route to the newly eroded Beaverhead-Jefferson River valley and created the northwest-oriented Clark Fork valley.

• “Great Divide River” flood waters were derived from immense west and southwest-oriented supra glacial melt water rivers flowing to the ice sheet western margin in Alberta. In time these huge supra glacial rivers carved deep ice-walled canyons into the ice sheet surface. At that time the Canadian Rocky Mountains in western Alberta and eastern British Columbia were just beginning to emerge and did not present a barrier to west-oriented flood flow as they do today. However, crustal warping had raised the continent’s western margin, which forced the west-oriented melt water floods to flow in south and southeast directions (and perhaps in north and northwest directions) once in British Columbia. Initially the south and southeast-oriented “Great Divide River” flood flow routes were located on a topographic surface as high as erosion surfaces preserved near crests of present day eastern British Columbia and western Alberta mountain ranges. However, as the “Great Divide River” was progressively dismembered headward erosion of deep valleys gradually lowered the floors of the “Great Divide River” flood flow channels so as to develop the deep south and southeast-oriented valleys presently located between the eastern British Columbia and western Alberta mountain ranges. The southeast-oriented Rocky Mountain Trench is one of these valleys and served as a major southeast-oriented “Great Divide River” flood flow route to western Montana. Flood waters moving on the Rocky Mountain Trench alignment at one time flowed across western Montana to the Yellowstone Plateau and then across Wyoming. This flood flow route supplied much of the melt water flood flow responsible for eroding the Missouri River drainage basin. Southeast-oriented flood flow from this “Great Divide River” flood flow route to the Missouri River drainage basin ended when headward erosion of the Columbia River valley and tributary valleys beheaded and reversed flood flow in the present day Clarks Fork valley. Subsequently headward erosion of Columbia River tributary valleys and of the other valleys associated with the Fraser River further dismembered the Rocky Mountain Trench “Great Divide River” flood flow route. Further north, a major flood flow reversal on what had been a major west-oriented melt water river created the east-oriented Peace River, which today flows across the Canadian Rocky Mountains from the Rocky Mountain Trench onto the Alberta plains.

Climate Change and a thin ice sheet replaces the thick ice sheet

• “Great Divide River” melt water flood flow routes supplied much of the water that eroded the present day Missouri River drainage basin. When the thick ice sheet melted to the point that it no longer stood high above the surrounding non glaciated surface, the ice-walled and ice-floored “Midcontinent Trench” canyon, which was being carved by the supra glacial “Midcontinent River”, sporadically captured southeast-oriented “Great Divide River” flood flow. I mention the possibility of these captures because they may explain alluvium covered  uplands in southeast Alberta, southwest Sakatchewan, and northeast Montana (e.g. Cypress Hills, Wood Mountain, and Flaxville uplands), although confirmation of the captures requires information from sources other than topographic maps. Such captures could have helped erode the northeast-oriented regional slope and initiated many of the deep north and northeast-oriented Rocky Mountain valleys found in the Missouri River and tributary river headwaters areas at a time when most melt water was flowing in a south direction. In any case, melt water floods throughout most of the ice sheet melt history were oriented in south directions, with much of the flood water east of the present day east-west continental divide flowing to the Gulf of Mexico and much of the flood water west of the continental divide flowing to Gulf of California. Movement of immense melt water floods into the Gulf of Mexico displaced warm Gulf of Mexico waters and established oceanic circulation patterns that generally warmed the Northern Hemisphere. Similar ocean circulation patterns may have been established in the Pacific Ocean as well. These ocean circulation patterns probably contributed to the ice sheet’s rapid melt down and continued as long as melt water floods moved in a south direction.

• Late during the thick ice sheet melt down history giant south-oriented ice-walled and bedrock-floored canyons carved into the decaying ice sheet’s surface began to intersect with similar east, west, and north oriented ice-walled canyons. Intersection of these ice-walled and bedrock-floored canyons not only chopped the decaying ice sheet up into many smaller ice sheets, but it also opened new and shorter routes to adjacent ocean basins. At the same time crustal warping in the form of mountain and plateau uplift was opening up new outlets to adjacent ocean basins and causing massive flood flow reversals, which diverted south-oriented melt water floods in alternate directions (e. g. no longer could south-oriented melt water flood flow reach the Gulf of California). In other words, late during the thick ice sheet melt down history the massive south-oriented melt water floods were diverted to flow in a northeast and north directions (and in west and in northwest directions) and no longer displaced warm Gulf of Mexico (and Gulf of California waters) and instead displaced colder North Atlantic, North Pacific, and even Arctic Ocean water. The result was a significant change in ocean circulation patterns, which significantly changed Northern Hemisphere climates. Climatic conditions responsible for the thick ice sheet’s rapid melt down were replaced by climatic conditions that froze north oriented melt water floods on the floors of the giant ice-walled and bedrock-floored canyons. Freezing of the north oriented melt water floods in turn caused incoming north and northeast oriented flood waters to also freeze and in time the floors of the ice-walled and bedrock-floored canyons were filled with frozen melt water and a thin ice sheet evolved. The resulting thin ice sheet was composed of rejuvenated thick ice sheet remnants surrounded by frozen melt water located on floors of the former ice-walled and bedrock-floored canyons.

• Development of the thin ice sheet ended the massive melt water floods, however the north and northeast-oriented drainage in the valleys the previous melt water floods had eroded continued to flow toward the former thick ice sheet southwest margin. Upon reaching the ice sheet margin the north and northeast-oriented valleys were blocked and the north and northeast-oriented drainage was forced spill over drainage divides until it reached south and southeast-oriented valleys. This spillage of north and northeast-oriented drainage across drainage divides between north and northeast-oriented valleys resulted in the present day North Dakota and northeast Montana Missouri River route. Unlike the previous thick ice sheet the thin ice sheet did not deeply erode the underlying bedrock, although the thin ice sheet did move bedrock materials around. Melt water floods froze from the top down, which meant where water was deep there was still liquid water under the ice. At the same time where water was shallow freezing also included water saturated bedrock under the ice. The liquid water under some ice sheet segments provided lubrication enabling relatively easy movement of those ice sheet segments. Such movements often included bedrock masses which were frozen solid with the overlying ice. Evidence for such ice thrust bedrock masses can be seen on topographic maps, especially on floors of the former ice-walled and bedrock-floored canyons. The climatic change that resulted in the thin ice sheet was probably also responsible for formation of alpine glaciers in the newly emerged Rocky Mountains.

• Finally, in time the thin ice sheet melted, as did many of the alpine glaciers. Thin ice sheet melt water floods also locally altered landscape features, although the thin ice sheet melt water floods did not significantly alter the previously established drainage routes. It is possible thin ice sheet melting also caused oscillating climates  and there may have been more than one thin ice sheet. Like with the thick ice sheet, the thin ice sheet melt water initially flowed south to the Gulf of Mexico and later flowed in northeast and north directions. The history of the thick ice sheet final melt down stages may have been repeated one or more times before all ice sheet remnants disappeared from the North American continent. Probably the final ice sheet remnants to melt were the thick ice sheet remnants, which had been embedded in the frozen melt water floods. In the Missouri River drainage basin area these thick ice sheet remnants were located in the present day Missouri Coteau region, located between the North and South Dakota Missouri River valley and the northeast and east-facing Missouri Escarpment, and the Prairie Coteau upland region, located between the west-facing Prairie Coteau Escarpment in eastern South Dakota and northeast-facing Prairie Coteau Escarpment in northeast South Dakota and southwest Minnesota. On topographic maps these regions are poorly drained, and have numerous lakes and depressions, low hills, and other evidence of glacial deposition. Floors of the former ice-walled and bedrock-floored canyons are much better drained and while evidence of glacial features can be found on topographic maps, the evidence is quite different from that found in the Missouri and Prairie Coteau areas.