A geomorphic history based on topographic map evidence

The Moreau River-Cherry Creek drainage divide area discussed here is located in western South Dakota, USA. Although detailed topographic maps of the Moreau River-Cherry Creek drainage divide area have been available for more than fifty years detailed map evidence has not previously been used to interpret the region’s geomorphic history. The interpretation provided here is based entirely on topographic map evidence. The Moreau River-Cherry Creek drainage divide area is interpreted to have been eroded during immense southeast-oriented flood events, the first of which flowed on a topographic surface at least as high as the highest points in the present-day drainage divide area. Flood erosion ended when headward erosion of the east-northeast-oriented Moreau River valley captured all 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 South Dakota Moreau River-Cherry Creek drainage divide 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 essay 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 melt water 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 Moreau River-Cherry Creek drainage divide area landform evidence will be regarded as evidence supporting the “thick ice sheet that melted fast” paradigm.

Moreau River-Cherry Creek drainage divide area general location map

Figure 1: Moreau River-Cherry Creek drainage divide area general location map (select and click on maps to enlarge). National Geographic Society map digitally presented using National Geographic Society TOPO software.

Figure 1 provides a Moreau River-Cherry Creek drainage divide area general location map. The Moreau River begins with a southeast orientation near the Montana-South Dakota border, just east of the northeast oriented Little Missouri River, and then turns to flow east-northeast and northeast to join the south and southeast-oriented Missouri River as a barbed tributary. The western extension of Cherry Creek is Sulphur Creek, which begins southwest of Mud Butte, South Dakota and flows southeast to southeast-oriented Cherry Creek, which flows to the northeast oriented Cheyenne River. The Cheyenne River flows northeast to also join the south and southeast-oriented Missouri River as a barbed tributary. North of the Moreau River drainage basin is the east-oriented Grand River drainage basin and another essay addresses landform evidence along the South Fork Grand River-Moreau River drainage divide (essay can be found under Moreau River or SD Grand River on the sidebar category list). Note the many southeast-oriented tributaries to the east-northeast and northeast oriented Moreau River and to the southeast-oriented Sulphur Creek-Cherry Creek and northeast oriented Cheyenne River. This essay interprets the southeast-oriented tributaries to be evidence the east-northeast and northeast oriented Moreau River valley, the northeast oriented Cheyenne River valley, and the southeast-oriented Cherry Creek-Sulphur Creek valley eroded headward to capture multiple southeast-oriented flood flow channels, such as might be found in an immense southeast-oriented anastomosing channel complex that was moving an immense flood across the entire figure 1 region. While not addressed here the southeast-oriented flood waters were captured by headward erosion of the northeast and north oriented Little Missouri River valley and the flood waters were diverted to somewhere in North Dakota and probably beyond. Another essay addresses Little Missouri-Moreau River drainage divide evidence and can be found under Moreau River or Little Missouri River on the sidebar category list. In this essay a case will be made that the northeast oriented Cheyenne River-southeast-oriented Cherry Creek-Sulphur Creek valley eroded headward to capture the southeast-oriented flood water prior to headward erosion of the northeast and east-northeast oriented Moreau River valley.

Moreau River-Cherry Creek drainage divide area detailed location map

Figure 2: Moreau River-Cherry Creek drainage divide area detailed location map. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 2 provides a detailed Moreau River-Cherry Creek drainage divide area location map. The Moreau River is the east-oriented stream flowing across the top half of figure 2. The Cheyenne River flows northeast across the figure 2 south center and southeast quadrant. Cherry Creek and its western Sulphur Creek extension begin in the figure 2 west center and flow southeast to join the northeast-oriented Cheyenne River at Cherry Creek, South Dakota. Note most Cheyenne River tributaries from the north are southeast-oriented  and many Cheyenne River tributaries from the south are northwest-oriented. Moreau River tributaries from the north are southeast-oriented and from the south are often northwest-oriented. Most tributaries to southeast-oriented Sulphur Creek-Cherry Creek shown on figure 2 are from the north and are southeast-oriented. This southeast-northwest orientation of major trunk stream tributaries is evidence major trunk stream valleys were eroded headward across multiple southeast-oriented flood flow channels and in sequence captured southeast-oriented flood flow. In the context of the figure 2 evidence the northeast-oriented Cheyenne River valley eroded southwest first to capture southeast-oriented flood flow and to divert flood waters northeast into northeastern South Dakota and probably beyond. Headward erosion of the southeast-oriented Cherry Creek-Sulphur Creek valley next captured southeast-oriented flood flow and provided flood waters a more direct route to the northeast-oriented Cheyenne River valley. Finally the east-oriented Moreau River valley eroded headward or west to capture the southeast-oriented flood waters and to divert the flood flow east and northeast into northeastern South Dakota and beyond. Headward erosion of the Moreau River valley beheaded all southeast-oriented flow moving over the present day Moreau River-Cherry Creek drainage divide and in the process created the Moreau River-Cherry Creek drainage divide. Detailed maps in this essay begin in the west and proceed east along the Moreau River-Cherry Creek drainage divide and then follow southeast-oriented Cherry Creek tributaries downstream to the Cherry Creek-Cheyenne River confluence area.

South Fork Moreau River-Sulphur Creek drainage divide near Deers Ears Butte

Figure 3: South Fork Moreau River-Sulphur Creek drainage divide near Deers Ears Butte. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 3 illustrates an area near the Moreau River-Cherry Creek drainage divide west end. Southeast-oriented drainage flows to southeast-oriented Sulphur Creek (seen in the figure 3 southeast corner). Northwest-oriented drainage in the figure 3 northwest corner is flowing to southeast-oriented (west of figure 3) and north-oriented Frog Creek, which flows to the east-and northeast-oriented South Fork Moreau River. In the figure 3 northeast corner Trail Creek begins as a southeast-oriented stream and then turns to flow northeast (and later northwest) to the South Fork Moreau River. The unnamed (in figure 3) north-northwest-oriented creek following the road northwest of Deers Ears Butte is Warren Creek and the north-northwest-oriented unnamed (in figure 3) creek between Warren Creek and Frog Creek is Hans Creek. Events recorded by this figure 3 evidence begin with multiple and ever-changing anastomosing southeast-oriented flood flow channels crossing the figure 3 map area, probably flowing across a topographic surface at least as high as the highest figure 3 elevations today. Headward erosion of the southeast-oriented Cherry Creek-Sulphur Creek valley then captured the southeast-oriented flood flow and diverted the flood water more directly to the northeast-oriented Cheyenne River valley. Southeast-oriented flood flow then eroded southeast-oriented headcuts or valleys northwest and proceeded to lower the regional topographic surface south of the present day Moreau River-Cherry Creek drainage divide to look approximately as the regional surface looks today. As this was happening headward erosion of the South Fork Moreau River valley (north of the figure 3 map area) was capturing the southeast-oriented flood flow that had been moving across the figure 3 map area. These captures occurred in sequence from east to west and flood waters located on the northwest ends of beheaded southeast-oriented flood flow routes (between the newly eroded South Fork Moreau River valley and the present day Moreau River-Cherry Creek drainage divide) reversed flow direction to create the northwest-oriented headwaters of north-oriented South Fork Moreau River tributaries and to create the present day Moreau River-Cherry Creek drainage divide.

South Fork Moreau River-Sulphur Creek drainage divide near Mud Buttes

Figure 4: South Fork Moreau River-Sulphur Creek drainage divide near Mud Buttes. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 4 illustrates the South Fork Moreau River-Sulphur Creek drainage divide region immediately east of the figure 3 map area (there is an overlap area). The east-oriented South Fork Moreau River is located immediately north of the figure 4 map area. In the figure 4 northwest corner southeast-oriented Trail Creek headwaters (see figure 3) have turned northeast and then turn northwest to flow to the east-oriented South Fork Moreau River. Further east along the figure 3 north edge are northwest oriented headwaters of barbed tributaries flowing to the east-oriented South Fork Moreau River. Southeast-oriented drainage flows to southeast-oriented Sulphur Creek (seen briefly in the figure 4 southwest corner). Events recorded by figure 4 evidence begin with southeast-oriented flood flow moving across the entire figure 4 map region, probably flowing on a topographic surface at least as high as the highest figure 4 elevations today. Headward erosion of the deep southeast-oriented Cherry Creek-Sulphur Creek valley then captured the flood water and diverted the flood flow more directly to the northeast-oriented Cheyenne River valley. Headward erosion of southeast-oriented headcuts or valleys from the newly eroded and deep Sulphur Creek valley north wall then began to lower the regional landscape south of the present day Moreau River-Cherry Creek drainage divide to look approximately as it does today. As this was happening headward erosion of the deep east-oriented South Fork Moreau River valley to the north began to capture southeast-oriented flood flow that had been moving across the figure 4 map area. The captures occurred in sequence from east to west. Flood water located on northwest ends of beheaded southeast-oriented flood flow routes (between the newly eroded South Fork Moreau River valley and the present day Moreau River-Cherry Creek drainage divide) reversed flow direction to create northwest and north-oriented South Fork Moreau River tributary valleys and to create the present day South Fork Moreau River-Sulphur Creek (Moreau River-Cherry Creek) drainage divide.

Moreau River-Sulphur Creek drainage divide in Cedar Canyon and Maurine areas

Figure 5: Moreau River-Cherry Creek drainage divide in Cedar Canyon and Maurine areas. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 5 illustrates the Moreau River-Sulphur Creek drainage divide area east of the figure 4 map area (there is an overlap area). Northwest of the figure 5 northwest corner the South Fork Moreau flows northeast to join the North Fork Moreau River and from this region east the Moreau River flows east-northeast. Southeast-oriented drainage in figure 5 flows to southeast-oriented Sulphur Creek. North and northwest-oriented drainage flows to the east-oriented Moreau River. Flowing in a shallow valley across the figure 5 northeast edge are headwaters of east- and northeast-oriented Deep Creek. Events recorded by the figure 5 evidence are similar to the events recorded by the figure 3 and 4 evidence, although figure 5 evidence provides additional insights into what happened. First flood water moved in a southeast direction across the entire figure 5 map area on a topographic at least as high as the highest figure 5 elevations today. Second headward erosion of the deep southeast-oriented Sulphur Creek valley captured the flood water and diverted the flood flow more directly to the northeast-oriented Cheyenne River valley. Southeast-oriented flood flow then eroded southeast-oriented headcuts or valleys headward into the high level topographic surface and in the eastern two-thirds of the figure 5 map area those headcuts encountered some type of resistant rock material just south of the highway, resulting in the south-facing escarpment located there today. As this was happening the deep east-oriented Moreau River valley eroded west and started to erode a large headcut or valley southwest and west along what is today the Deep Creek alignment, but it too encountered resistant rock material just northwest of Maurine while the northern portion of the large and actively eroding Moreau River valley was able to erode headward around the resistant rock mass. As the large Moreau River valley eroded west it beheaded southeast-oriented flood flow routes and flood waters on the northwest ends of those beheaded flood flow routes reversed flow direction to create north and northwest-oriented tributary valleys to the newly eroded east-northeast oriented Moreau River valley. In the figure 5 northwest corner are northwest-oriented tributaries to north and northwest-oriented Beverly Creek, which provide evidence as to how enough north-oriented water to erode the north-oriented Cedar Canyon valley was obtained. Reversed flow that eroded the Cedar Canyon valley captured yet to be beheaded southeast-oriented flood flow on the Beverly Creek alignment and that capture enabled reversed flow to erode the deep Cedar Canyon valley. Subsequently that southeast-oriented flood flow was captured by the Sulphur Creek valley because apparently in the western third of the figure 5 map area the southeast-oriented headcuts did not encounter resistant rock material and were able to continue eroding northwest. However, that capture was short-lived because soon thereafter headward erosion of the Moreau River valley beheaded the Beverly Creek southeast-oriented flood flow route causing a reversal of flow there also.

Deep Creek-Cherry Creek drainage divide east of Fox Ridge

Figure 6: Deep Creek-Cherry Creek drainage divide east of Fox Ridge. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 6 illustrates the Deep Creek (Moreau River)-Cherry Creek drainage divide area immediately east of the figure 5 map area and there is an overlap area. South of figure 6 the name of Sulphur Creek changes to become Cherry Creek. Deep Creek flows east just north of the figure 6 map area and north-northwest-oriented Flint Creek (figure 6 north center) flows to Deep Creek. Northeast-oriented Flint Rock Creek (figure 6 northeast corner) flows directly to the Moreau River. The arc-shaped escarpments at the head of southeast-oriented Brushy Creek and southeast-oriented North Branch Creek are abandoned headcuts carved by southeast-oriented flood water to the Cherry Creek valley and northeast-oriented Cheyenne River valley just prior to headward erosion of east-oriented Deep Creek-Moreau River valley headcut, which captured the southeast-oriented flood flow and diverted the flood waters to the newly eroded east-northeast-oriented Moreau River  valley. These arc-shaped escarpments may be part of the northwest wall of a much large abandoned southeast-oriented headcut south-southeast of the north-northwest-oriented Flint Creek headwaters. If so flood waters eroding that much larger southeast-oriented headcut were captured by headward erosion of the northeast-oriented Flint Rock Creek valley and diverted to what was then the actively eroding Moreau River valley. Subsequently the Moreau River valley eroded west and beheaded southeast-oriented flood flow on the Flint Creek flow route causing a reversal of flood flow that eroded the present day Flint Creek valley.  Fox Ridge and Signal Butte are probably capped by some type of resistant rock material and there elevations provide a minimum elevation for the topographic surface that probably prevailed prior to the flood erosion.

Flint Rock Creek-Red Scaffold Creek drainage divide near Faith

Figure 7: Flint Rock Creek-Red Scaffold Creek drainage divide near Faith. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 7 illustrates the Moreau River-Cherry Creek drainage divide area east of the figure 6 map area and provides an overlap area. Northeast-oriented Flint Rock Creek flows across the figure 7 northwest corner. Southeast-oriented Red Scaffold Creek in the figure 7 southwest corner is a major Cherry Creek tributary. The South Fork of Flint Rock Creek begins north of Faith, South Dakota and after flowing northeast and east it turns to flow northwest and also has northwest-oriented tributaries. Southeast-oriented drainage along the figure 7 south edge all flows to southeast-oriented Cherry Creek. Events recorded by the figure 7 evidence are similar to events recorded by evidence in previous figures. Southeast-oriented flood waters flowed over the entire the figure 7 map region probably on a topographic surface much higher than the highest figure 7 elevations today. Headward erosion of the deep Cherry Creek valley captured the southeast-oriented flood flow and diverted the flood water more directly to the northeast-oriented Cheyenne River. Southeast-oriented headcuts or valleys eroded northwest from the newly eroded north Cherry Creek valley wall and stripped the area south of the present day drainage divide to look approximately as it does today. At the same time the deep Moreau River valley was eroding west to the north of the figure 7 map area and was proceeding to behead southeast-oriented flood flow routes as it progressed west. But before it could behead southeast-oriented flood flow routes across the figure 7 map area the northeast-oriented Flint Rock Creek valley eroded southwest to progressively behead and reverse flow on the northwest ends of flow flood routes across the figure 7 map area. Southeast-oriented flood flow to newly eroded Flint Rock Creek valley was soon captured by headward erosion of Moreau River valley and the figure 7 landscape has changed little since.

Moreau River-Cherry Creek drainage divide west of Red Elm

Figure 8: Moreau River-Cherry Creek drainage divide west of Red Elm. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 8 illustrates the Moreau River-Cherry Creek drainage divide area east of the figure 7 map area and provides a significant overlap area. Rattlesnake Creek is one of the easternmost large southeast-oriented Cherry Creek tributaries before southeast-oriented Cherry Creek joins the northeast-oriented Cheyenne River. A short distance east of Red Elm the drainage divide becomes the Moreau River-Cheyenne River drainage divide and evidence along that divide is addressed the Moreau River-Cheyenne River drainage divide (east end) essay found under Moreau River on the sidebar category list. Northeast, east, and northwest oriented South Fork Flint Rock Creek is located in figure 8 northwest corner. Northwest-oriented drainage along the figure 8 north edge flows to the east-northeast-oriented Moreau River (north of the figure 8 map area). All southeast-oriented drainage flows to southeast-oriented Cherry Creek. Events recorded by the figure 8 evidence are similar to events recorded by previous figure evidence. Flood waters flowed southeast across the entire figure 8 map area probably on a topographic higher than the highest figure 8 elevations today. Headward erosion of the deep southeast-oriented Cherry Creek valley captured the southeast-oriented flood water and diverted the flood water more directly to the northeast-oriented Cheyenne River valley. Southeast-oriented flood flow then eroded the newly eroded Cherry Creek valley north wall eroding headcuts or valleys northwest to the approximate position of the present day Moreau River-Cherry Creek drainage divide (although earlier headcuts and valleys may have removed significant material above the present day drainage divide surface). At the same time the deep east-northeast-oriented Moreau River valley was eroding west and beheading southeast-oriented flood flow routes that had been flowing across the figure 8 map region. Floodwaters on the northwest ends of beheaded flood low routes reversed flow direction to create northwest and north-oriented Moreau River tributaries and the present day Moreau River-Cherry Creek drainage divide.

Cherry Creek drainage basin northeast of Red Scaffold

Figure 9: Cherry Creek drainage basin northeast of Red Scaffold. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 9 illustrates the region just south of the figure 8 map region and is following Rattlesnake Creek  downstream as it flows to the southeast-oriented Cherry Creek valley (there is no overlap with figure 8, but Rattlesnake Creek should serve as reference feature). Southeast-oriented Cherry Creek is located in the figure 9 southwest corner. Also in the figure 9 southwest corner is the confluence of Cherry Creek and Red Scaffold Creek. Red Scaffold Creek headwaters were observed in figure 7 above. Note how southeast-oriented flood waters have deeply eroded what was at one time the newly eroded and deep north Cherry Creek valley wall. Also note how Cherry Creek has eroded a deeper valley into a surface defined by benches in the Red Scaffold, South Dakota area. Apparently more than one headcut eroded northwest along the Cherry Creek valley. The first (or at least an earlier headcut) eroded a wider and shallower valley headward and was followed by headward erosion of the deeper and narrower inner valley. Reasons why two or more headcuts eroded northwest along the Cherry Creek valley cannot be determined from evidence presented here, but probably are related to Cheyenne River base level lowering somewhere to the northeast. Likewise the southeast-oriented flood water source cannot be determined from evidence presented here, although rapid melting of a large North American ice sheet would be a logical flood water source.

Cherry Creek valley upstream from Cherry Creek-Cheyenne River confluence

Figure 10: Cherry Creek valley upstream from Cherry Creek-Cheyenne River confluence. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 10 illustrates the Cherry Creek valley south and slightly east of the figure 9 map area (there is some overlap for reference). Cherry Creek, South Dakota is located at the Cherry Creek-Cheyenne River confluence and the northeast-oriented Cheyenne River is just barely seen in the extreme southeast corner of figure 10. Rattlesnake Creek (unnamed in figure 10) is the larger south-southeast-oriented Cherry Creek tributary located in the figure 10 northwest corner and is west of south-oriented Ash Creek. Straighthead Draw, Horn Draw, and Little Dog Draw all have been eroded into what appears to be a high level bench that probably defines the southeast-oriented floor of the first (or at least an earlier) southeast-oriented Cherry Creek headcut or valley that eroded northwest to capture the southeast-oriented flood flow and to divert the flood water to what was then a higher level Cheyenne River valley. For reasons that cannot be determined here base level for the Cheyenne River valley was then significantly lowered somewhere in the northeast and a deeper inner headcut (or valley) eroded headward to the Cherry Creek valley and then northwest along the Cherry Creek valley to the northwest. Evidence for these two separate headcuts was either not present along the Moreau River-Cherry Creek drainage divide and/or I missed the evidence when preparing my figure discussion, although evidence within the Cherry Creek valley is easy to observe.

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 detailed topographic 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 used here were created using National Geographic Society 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.