A geomorphic history based on topographic map evidence

The North Fork Grand River drainage basin is located in southwest North Dakota and northwest South Dakota, USA. Although detailed topographic maps of the North Fork Grand River drainage basin have been available for more than fifty years detailed map evidence has not previously been used to interpret the North Fork Grand River drainage basin geomorphic history. The interpretation provided here is based entirely on topographic map evidence. Based on the topographic map evidence the North Fork Grand River drainage basin is interpreted to have been eroded during immense flood events, the first of which flowed on a topographic surface at least as high as the highest points in the present-day North Fork Grand River drainage basin, and which stripped the North Fork Grand River drainage basin bedrock layers as deep and broad headcuts, often several kilometers in width, eroded headward along routes of the present-day southeast-oriented North Fork Grand River valley segments and various southeast-oriented tributaries. Flood erosion ended when headward erosion of the deep north and northeast-oriented Little Missouri River headcut captured the southeast-oriented flood flow.

Preface:

The following interpretation of detailed topographic map evidence is provided as evidence in the Missouri River drainage basin landform origins research project, which is compiling similar evidence for all major drainage divides contained within the Missouri River drainage basin and for all major drainage divides with and within certain adjacent drainage basins. The research project is interpreting evidence in the context of a previously unexplored geomorphology paradigm, which is briefly described in the introduction below. Project essays are listed on the sidebar category list under their appropriate Missouri River tributary drainage basin, Missouri River segment drainage basin (by state), and/or state in which the Missouri River drainage basin is located.

Introduction:

• The purpose of this essay is to use topographic map interpretation methods to explore North Fork Grand River drainage basin area landform origins. Map interpretation methods can be used to unravel many geomorphic events leading up to formation of present-day drainage routes and development of other landform features. While each detailed topographic map feature provides detailed evidence to be explained, the solution must be consistent with explanations for adjacent area map evidence as well as solutions to big picture map evidence puzzles. I invite readers to improve upon my solutions or to propose alternate solutions that better explain evidence and are also consistent with adjacent map area and big picture evidence. Readers may do so either by making comments here or by writing and publishing their own essays and then by leaving a link to those essays in a comment here.

• This essay is also exploring a paradigm in which erosional landforms are interpreted as evidence left by immense glacial melt water floods. Implied in that interpretation is the immense floods were derived from a thick North American ice sheet that created a deep “hole” in the North American continent and also melted fast. The previously unexplored paradigm being tested in this and similar essays is a thick North American ice sheet, comparable in thickness to the present day Antarctic ice sheet, occupied approximately the North American region usually recognized to have been glaciated and through its weight and erosive actions created a “deep” North American “hole”, through its weight and deep erosion (and perhaps deposition) along major south-oriented meltwater flow routes caused significant crustal warping and tectonic change, through its action of melting fast produced immense floods that flowed across the continent, and through its action of melting fast systematically opened up space in the ice sheet created “hole” so headward erosion of newly developed north-oriented drainage systems captured immense south-oriented melt water floods and diverted immense melt water floods north into space the ice sheet had once occupied.

• If this previously unexplored paradigm is correct the geographic region explored by this essay should contain evidence of immense floods that were captured by headward erosion of new valley systems so as to cause the floods to flow in a different direction. Ability of this previously unexplored paradigm to explain North Fork Grand River drainage basin area landform evidence will be regarded as evidence supporting the “thick ice sheet that melted fast” paradigm.

North Fork Grand River Location

Figure 1: North Fork Grand River in North and South Dakota (select and click on maps to enlarge). United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

The southeast-oriented North Fork Grand River drainage basin is located in Bowman and Adams counties in southwest North Dakota and in Harding and Perkins counties in northwest South Dakota. West and northwest of the North Fork Grand River drainage basin is the north-oriented Little Missouri River valley and the north-oriented Deep Creek drainage basin (unnamed north-oriented Little Missouri River tributary flowing north of Rhame in figure 2). North of the North Fork Grand River drainage basin is the southeast-oriented Cedar Creek drainage basin, which flows eventually to the Cannonball River. South of the North Fork Grand River drainage basin are drainage basins of southeast-oriented tributaries flowing to the east-oriented South Fork Grand River. The North and South Forks of the Grand River join at the modern-day Shadehill Reservoir to form the southeast-oriented Grand River. The essay interpreting Little Missouri-North Fork Grand River drainage divide landforms determined that massive southeast-oriented floods crossed that drainage to enter the North Fork Grand River drainage basin. East of the drainage divide streams shown in figure 1 have a remarkable southeast orientation. This southeast-oriented drainage alignment suggests erosion of the entire region by a common southeast-oriented flood event. The north-oriented Little Missouri River appears to have beheaded southeast-oriented flood flow. This beheading can be explained by headward erosion of a deep north-oriented Little Missouri River valley headcut during the southeast-oriented flood event. Evidence in the North Fork Grand River drainage basin to support these interpretations will be investigated in the following essay. Additional evidence is discussed in essays related to adjacent drainage basins.

Deep Creek-Buffalo Creek through valleys north of Bowman

Figure 2: Deep Creek-Buffalo Creek through valleys north of Bowman. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

A set of through valleys linking the north-oriented Little Missouri River valley with the southeast oriented North Fork Grand River is north of Bowman. The drainage divide follows the north-northeast ridge, including Twin Buttes, just north of Bowman. Northwest of this ridge northwest-oriented drainage flows to north-oriented Deep Creek and the Little Missouri River. Southeast of the ridge is Buffalo Creek, which flows southeast to the North Fork Grand River. Northeast-oriented drainage in the northeast corner of figure 2 flows to the southeast and east-oriented Cedar Creek and then the Cannonball River. Multiple through valleys cross the north-northeast oriented ridge and suggest a large southeast-oriented flood moving from the Deep Creek drainage basin to the Buffalo Creek drainage basin eroded the entire region. The present day drainage divide would have been created when headward erosion of the deep north-oriented Little Missouri River valley headcut and its tributary north-oriented Deep Creek headcut captured the southeast-oriented flood flow. Floodwaters on the northwest end of the beheaded southeast-oriented Deep Creek-Buffalo Creek flood flow reversed flow direction to move toward the deep and newly eroded Deep Creek headcut. Reversed floodwaters eroded present-day valleys of the northwest-oriented Deep Creek tributaries, while floodwaters further southeast continued to flow southeast and eroded the present-day Buffalo Creek valley. Twin Buttes elevations provide a minimum estimate of the height of the topographic surface on which floodwaters originally flowed. A large southeast-oriented headcut at least as deep as the present day buttes are tall and at least several kilometers in width eroded northwest along the Buffalo Creek route while the north-oriented Little Missouri River valley headcut and Deep Creek headcut eroded south cutting into that same topographic surface.

Through valleys linking North Fork Grand River and Lone Tree Creek

Figure 3: Through valleys linking North Fork Grand River and Lone Tree Creek. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Figure 3 illustrates an area between the east oriented North Fork Grand River and east-oriented Lone Tree Creek. Similar regions can be found throughout the North Fork Grand River drainage basin. Note how northwest to southeast-oriented through valleys and intersecting southwest to northeast-oriented valleys link the two present-day stream valleys. This anastomosing complex of through valleys can best be explained in the context of an immense flood that initially moved southeast across the region. The southeast-oriented flood initiated the carving of a southeast-oriented anastomosing channel complex that was systematically captured by headward of the deeper Lone Tree Creek and North Fork Grand River valley headcuts. The Lone Tree Creek valley headcut eroded west first and captured the southeast-oriented floodwaters. Next the North Fork Grand River valley headcut eroded west. The newly eroded North Fork Grand River valley headcut was deep enough and southeast-oriented floodwaters were not contained in the channels shown. As a result some southeast-oriented floodwaters from west of the actively eroding North Fork Grand River headcut face was able to flow in a northeast direction toward the newly eroded deep North Fork Grand River valley headcut. This northeast-oriented flood water carved the northeast-oriented through valleys we see today. The anastomosing channel complex shape and nature was constantly evolving as progressively deeper headcuts eroded headward across the region and systematically lowered the regional landscape. The landscape we see today represents the anastomosing channel complex status at the time the southeast-oriented floodwaters were beheaded by headward erosion of the deep north-oriented Little Missouri River valley headcut.

North Fork Grand River elbow of capture

Figure 4: North Fork Grand River elbow of capture. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

The southeast-oriented North Fork Grand River jogs northeast at the present-day Bowman-Haley Reservoir location before continuing southeast. This jog represents an elbow of capture where a deeper northeast-oriented headcut captured the entire upstream North Fork Grand River drainage basin. What appears to be a relatively minor jog significantly changed the North Fork Grand River drainage basin size. Northwest-oriented tributaries can be seen flowing to the North Fork Grand River near this elbow of capture. Through valleys link headwaters of these northwest-oriented tributaries to southeast-oriented Nasty Creek headwaters, which flow southeast to the South Fork Grand River. Prior to the capture flood flow on the North Fork Grand River route upstream from the elbow of capture continued southeast along the present-day Nasty Creek route to the South Fork Grand River. How did this capture occur? Note how two southeast-oriented North Fork Grand River tributaries, Alkali Creek and Spring Creek, join at the Bowman-Haley Reservoir northwest end.  Other major tributaries shown in figure 4 are Lone Tree Creek, which flows east and northeast to the southeast-oriented North Fork Grand River upstream from Bowman-Haley Reservoir, and a short segment of northeast-oriented Crooked Creek, which joins the North Fork Grand River at the Bowman-Haley Reservoir southwest end. Prior to the capture southeast-oriented floodwaters eroded a southeast-oriented headcut along the Nasty Creek-upstream North Fork Grand River route and a parallel and deeper southeast-oriented headcut along the downstream North Fork Grand River-Alkali Creek and Spring Creek route. Flood water spilled in a northeast direction from the southwestern headcut to the northeastern headcut at the Bowman-Haley Reservoir location and eroded the northeast-oriented headcut that captured the upstream north Fork Grand River drainage basin.

Beheading of Lightning Creek by Stage Creek

Figure 5: Beheading of Lightning Creek by Stage Creek. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Captures also occurred within the North Fork Grand River drainage basin. Figure 5 illustrates how south-oriented Stage Creek beheaded southeast-oriented Lightning Creek. Stage Creek flows south to join southeast-oriented Spring Creek upstream from Bowman-Haley Reservoir. Lightning Creek flows southeast to join the southeast-oriented North Fork Grand River at a point near the North Dakota-South Dakota state line. Lightning Creek begins in southeast-oriented escarpment-surrounded basin or abandoned headcut located in the center of figure 5. Both northeast and southwest of that upland through valleys link the southeast-oriented Lightning Creek valley with the south-oriented Stage Creek valley. Evolution of this landscape began when southeast-oriented floodwaters flowing on a topographic surface at least as high as the headcut upland elevation eroded the southeast-oriented Lightning Creek valley headcut northwest to the present headcut upland location. For some reason, indeterminable from the topographic map, headward erosion slowed or ceased while tributary headcuts eroded both northeast and southwest of the headcut upland obstruction. At the same time headward erosion of the deeper North Fork Grand River-Spring Creek-Stage Creek headcut beheaded floodwaters using the flow route to Lightning Creek southwest of the upland and then floodwaters using the flow route to Lightning Creek were beheaded northeast of the upland. At the time of the capture floodwaters were using both the Lightning Creek route and the Stage Creek-Spring Creek-North Fork Grand River route and both routes were channels in an anastomosing channel complex.

Horse Creek headwaters

Figure 6: Horse Creek headwaters. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Horse Creek (unnamed in figure 6) begins at the northeast end of the Lodge Pole Buttes and flows northeast, then turns southeast and as shown in figure 7 turns north to join the North Fork Grand River. Figure 6 illustrates how Horse Creek headwaters are linked to northwest-oriented headwaters of an unnamed north-northeast oriented North Fork Grand River tributary and to the north-northwest oriented Teeter Creek, which also flows to the North Fork Grand River. Note how a northwest to southeast oriented through valley links the southeast-oriented Horse Creek with the northwest-oriented streams. Evidence shown in figure 6 can be explained by a major southeast-oriented flood event, which caused headward erosion of the southeast-oriented headcut along the present-day Horse Creek route (the headcut probably was at least as deep as the present-day Lodge Pole Buttes stand above the surrounding landscape).  At the same time, to the north a deeper parallel southeast-oriented headcut was being eroded headward along the present-day North Fork Grand River route. The flood event was so immense southeast-oriented floodwaters spilled north to the deeper North Fork Grand River headcut route. This north-oriented flood water spillage eroded deep north-oriented headcuts south from the deep North Fork Grand River that beheaded southeast-oriented flood flow moving to the Horse Creek drainage basin and reversed flow on the northwest ends of the beheaded southeast-oriented flood flow routes.

Horse Creek elbow of capture

Figure 7: Horse Creek elbow of capture. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

The beheading of the Horse Creek headwaters was illustrated in figure 6. Figure 7 illustrates the Horse Creek elbow of capture where southeast-oriented flood flow was captured and diverted north to the southeast-oriented North Fork Grand River. Note how Horse Creek flows in a southeast-oriented valley and then turns to flow in a north-northwest oriented valley to the southeast-oriented North Fork Grand River. Also note northwest oriented tributaries flowing to the Horse Creek elbow of capture. Evidence in figure 8 can be explained by a southeast-oriented flood event, which caused headward erosion of the southeast-oriented headcut along the present-day Horse Creek route (the headcut probably was a northwest extension of the present-day Lodgepole Creek drainage basin elevation as shown in figure 8). The southeast-oriented Lodgepole Creek-Horse Creek headcut was deep enough that flood water was being drawn in a south-southeast direction to reach it. At the same time, to the north a deeper southeast-oriented headcut was being eroded headward along the present-day North Fork Grand River route and beheaded the south-southeast oriented flood flow route to the Lodgepole Creek-Horse Creek headcut. Floodwaters moving south-southeast then were reversed to flow back in a north-northwest direction to the deeper North Fork Grand River headcut route. This reversed flood water eroded a deep north-northwest headcut that captured upstream Horse Creek flood flow and eroded the deep Horse Creek valley. As already discussed in the figure 6 discussion this process was repeated as the deep North Fork Grand River headcut eroded further northwest and west and the Horse Creek drainage basin was beheaded north of Lodge Pole Buttes.

Lodgepole Creek headwaters

Figure 8: Lodgepole Creek headwaters. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Figure 8 shows a big picture view of the Horse Creek elbow of capture (detailed view in figure 7) and its relationship to Lodgepole Creek headwaters. Southeast-oriented Lodgepole Creek begins on the nearly flat escarpment-surrounded upland surface northwest of Lodgepole. That nearly flat upland surface represents the floor of the southeast-oriented Lodgepole Creek-Horse Creek headcut that was beheaded by headward erosion of parallel and deeper North Fork Grand River headcut and reversed flow on a former south-southeast oriented flood flow route that captured Horse Creek and created the Horse Creek elbow of capture (see figure 7). The northwest oriented Horse Creek tributary adjacent to the nearly flat upland surface is linked by through valleys to southeast-oriented Lodgepole Creek tributaries, however northwest-oriented Horse Creek tributaries located further to the southwest are linked by through valleys to southeast-oriented Little Nasty Creek and the South Fork Grand River. Lodgepole Creek also is a South Fork Grand River tributary. Erosion of the landscape surrounding the nearly flat escarpment surrounded Lodgepole Creek upland surface provides a rough measure of the magnitude of Horse Creek capture event erosion. East of Horse Creek and north of the upland surface Bill Young Creek and Deer Creek have eroded north-oriented drainage basins south from the North Fork Grand River valley. As the deep North Fork Grand River headcut eroded northwest the Deer Creek headcut eroded south first, the Bill Young Creek headcut eroded south next, and the deep Horse Creek headcut eroded south and beheaded flood flow moving to the present-day Lodgepole Creek headwaters area. Figure 9 will provide a detailed look at through valleys linking the Horse Creek, Bill Young Creek, and Deer Creek valleys.

Anastomosing channels in the Bill Young Creek and Deer Creek drainage basins

Figure 9: Anastomosing channels in the Bill Young Creek and Deer Creek drainage basins. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Figure 9 shows a detailed map of the north-oriented Bill Young Creek and Deer Creek drainage basins. The north-oriented Horse Creek valley is west of figure 9. Both drainage basins originate at northeast escarpment bounding the nearly flat Lodgepole Creek upland surface (see figure 9 southwest corner) and empty into the southeast-oriented North Fork Grand River. Lodgepole Creek upland surface drainage is to the South Fork Grand River. Numerous through valleys link the north-oriented Bill Young Creek and Deer Creek valleys with each other and with the Horse Creek valley to the west and other north-oriented valleys to the east. These northwest to southeast and west to east oriented through valleys provide evidence the deep southeast-oriented North Fork Grand River valley headcut eroded headward as a network of southeast-oriented anastomosing channels not as a single valley. Through valleys linking the north-oriented drainage basins probably were systematically eroded by southeast-oriented floodwaters as the deep North Fork Grand River valley headcut eroded northwest. For example when the deep southeast-oriented North Fork valley headcut eroded northwest to the present-day Deer Creek mouth, a deep north-oriented tributary headcut eroded south to capture southeast-oriented flood water on what was still an upland surface and to erode deep southeast-oriented headcuts along those upland surface flow routes. The process was repeated by Bill Young Creek and then again by Horse Creek, although Horse Creek succeeded in beheading flow to the present-day Lodgepole Creek drainage basin.

Summary of North Fork Grand River landform interpretation evidence

• The North Fork Grand River begins in North Dakota and flows in a southeast direction into South Dakota where it joins the South Fork Grand River to form the Grand River. East-oriented North Fork Grand River headwaters are located along the north-oriented Little Missouri River drainage basin east edge. As demonstrated in the Little Missouri-North Fork Grand River drainage divide area essay multiple northwest to southeast oriented through valleys link southeast-oriented North Fork Grand River headwaters with northwest-oriented Little Missouri River tributaries. This evidence suggests southeast-oriented floods flowed across the drainage divide and eroded the southeast-oriented North Fork Grand River drainage basin. Further, this evidence also suggests flood flow to the North Fork Grand River drainage basin was beheaded when the deeper north-oriented Little Missouri River valley headcut and its tributary Deep Creek headcut eroded south.

• Evidence throughout the North Fork Grand River drainage suggests the North Fork valley and its tributary valleys originated as channels in an anastomosing channel complex that included both the North Fork and the South Fork drainage basins. North Fork tributaries beheaded southeast-oriented flood flow moving to the South Fork drainage basin area and at least one northeast-oriented North Fork tributary was beheaded by headward erosion of a deeper South Fork tributary valley. Since the North and South Forks join downstream to form the Grand River such beheading of each other’s drainage areas requires that for a time at least water from the point where the beheading took place could follow two quite different routes to the downstream Grand River valley. That is the way an anastomosing channel complex works. Similar anastomosing channel complex evidence is found where one North Fork tributary has beheaded the drainage basin of another and also in smaller-scale areas where anastomosing through valley complexes prevail.

• An aligned northwest to southeast oriented drainage pattern is evident throughout the North Fork Grand River drainage basin and provides further evidence of massive southeast-oriented floods.  This drainage alignment is particularly evident in the orientation of tributaries flowing into major trunk streams. These tributaries frequently flow in southeast or northwest directions and many are barbed tributaries (for example the tributary flows northwest to join the southeast-oriented North Fork Grand River). The barbed tributaries can be explained by headward erosion of deep headcuts across southeast-oriented flood flow routes. Floodwaters on the downstream ends of the beheaded flood flow routes then reversed direction to flow back to the newly eroded deep headcut and also to erode the present-day northwest-oriented tributary valleys.

• Throughout the North Fork Grand River drainage basin buttes and other upland provide evidence the southeast-oriented floods originally flowed on a topographic surface at least as high as the present-day highest elevations and were responsible for eroding the surrounding landscape we see today. For example headcuts eroded into the southwest walls of high buttes can only be explained if the headcut was eroded into a topographic surface at least as high as the present day butte.

Additional information and sources of maps studied

This essay has provided only a sample of the detailed topographic map evidence supporting the flood erosion interpretation. Many additional illustrations could be provided. Readers are encouraged to look at mosaics of the detailed maps to see the abundance of available data. Maps used in this study were created and published by the United States Geologic Survey and can be obtained directly from the United States Geological Survey and/or from dealers offering United States Geological Survey maps. Hard copy maps can also be observed at United States Geological Survey map depositories which are located throughout the United States and elsewhere. Illustrations were created using National Geographic TOPO software and digital map data. TOPO software and map data can be obtained from the National Geographic Society and/or dealers offering National Geographic Society digital map data.