A geomorphic history based on topographic map evidence

The Little Missouri River-Belle Fourche River drainage divide area discussed here is located in Wyoming’s northeast corner, where Wyoming, South Dakota and Montana meet. Although detailed topographic maps of this Little Missouri River-Belle Fourche River 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 Little Missouri River-Belle Fourche River 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 Little Powder 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 northeast Wyoming Little Missouri River-Belle Fourche River 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 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 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 northeast Wyoming Little Missouri River-Belle Fourche River drainage divide area landform evidence will be regarded as evidence supporting the “thick ice sheet that melted fast” paradigm.

Little Missouri River-Belle Fourche River drainage divide location map

Figure 1: Little Missouri River-Belle Fourche River drainage divide 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 Little Missouri River-Belle Fourche River general location map. The Little Missouri River begins in northeast Wyoming, west of Devils Tower, and flows in a northeast direction across Montana’s southeast corner and then flows at the figure 1 top into South Dakota. The Belle Fourche River begins south of Moorcroft in northeast Wyoming and flows northeast almost to the Montana border, then makes an abrupt turn to the southeast and flows into South Dakota and east of the figure 1 map area joins the northeast oriented Cheyenne River. This essay focuses on the northeast Wyoming Little Missouri River-Belle Fourche River drainage divide area. A separate essay discusses the Little Missouri River-Belle Fourche River drainage divide area north of Stoneville Flats, which is located northwest of the Belle Fourche River elbow of capture and can be found under Little Missouri River or Belle Fourche River on the sidebar category list. West of the northeast Wyoming Little Missouri River drainage basin is the north-oriented Little Powder River drainage basin, which is tributary to the northeast and north-northwest-oriented Powder River (shown in figure 1 northwest corner). The Wyoming and South Dakota Black Hills are located east of the Belle Fourche River northeast-oriented segment and southwest of the Belle Fourche River southeast-oriented segment with the Belle Fourche River valley roughly following the Black Hills northwest and northeast margins.

Northeast Wyoming Little Missouri-Belle Fourche River detailed location map

Figure 2: Northeast Wyoming Little Missouri-Belle Fourche River drainage divide detailed location map. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 2 provides a detailed location map for the northeast Wyoming Little Missouri River-Belle Fourche River drainage divide area. Arkansas Creek (unnamed in figure 1) flows northwest from near the Belle Fourche River elbow of capture to join the northeast-oriented Little Missouri River near Alzada, Montana. Following the Little Missouri River upstream or southwest from Alzada most Little Missouri River tributaries draining the Little Missouri River-Belle Fourche River drainage divide area flow in a northwest or north-oriented direction to reach the northeast-oriented Little Missouri River, although some begin as northeast-oriented streams. Tributaries to the northeast-oriented Belle Fourche River segment from the Little Missouri River-Belle Fourche River drainage divide area are generally southeast or east-oriented, although some begin as northeast-oriented streams. There is a northwest-southeast tributary drainage alignment observable in figure 2, although not as pronounced as the northwest-southeast tributary drainage alignment observable further north in the Little Missouri River drainage basin. Evidence presented below suggests the northwest-southeast tributary drainage alignment is at least to some extent independent of Black Hills structures and bedrock characteristics and is a relic of an immense southeast-oriented flood that was captured in sequence by headward erosion of the northeast-oriented Belle Fourche River valley, headward erosion of the northeast-oriented Little Missouri River valley, and then headward erosion of the north-oriented Little Powder River valley. The north-northwest-oriented Little Powder River flows across the figure 2 southwest corner. The flood source cannot be determined from evidence presented here, although by using evidence from a large number of similar essays published on this website it is possible to trace flood waters headward to a North American ice sheet location. Rapid melting of a continental ice sheet would be a logical source. Also, while evidence presented below demonstrates flood waters crossed Black Hills marginal areas other essays (found under Black Hills on the sidebar category list) demonstrate flood water flowed over what are today the Black Hills and originally flowed on a topographic surface significantly higher than floors of the present day Belle Fourche River and Little Missouri River valleys., Evidence presented here is not adequate to determine how that original topographic surface was changed by Black Hills uplift and other crustal warping, but crustal warping caused by a thick ice sheet’s weight would be a logical explanation for the crustal warping.

Little Missouri-Belle Fourche drainage divide southwest of Stoneville Flats

Figure 3: Little Missouri River-Belle Fourche River drainage divide southwest of Stoneville Flats. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 3 illustrates the Little Missouri River-Belle Fourche River drainage divide area at Stoneville Flats and southwest of Stoneville Flats. Stoneville Flats is the large northwest-southeast oriented valley connecting the Belle Fourche River elbow of capture in the southeast with the northeast-oriented Little Missouri River in the northwest and is drained by the northwest-oriented Arkansas Creek. The northwest-southeast Stoneville Flats valley and southeast-oriented Belle Fourche River segment alignment originated as a southeast-oriented flood flow route. Headward erosion of the northeast-oriented Little Missouri River valley beheaded and captured that southeast-oriented flood flow and flood waters already on the northwest end of the beheaded flood flow route reversed flow direction to flow northwest to the newly eroded Little Missouri River valley. Reversed flow on the Stoneville Flats alignment captured southeast-oriented flood flow on yet to be beheaded flood flow routes further to the southwest (e.g. southeast-oriented flood flow moving on what are today the Spring Creek, Boggy Creek, and Brushy Creek alignments). Capture of flood flow from these yet to be beheaded flood flow routes enabled the northeast-oriented Belle Fourche River valley to erode headward at a faster rate than the Little Missouri River valley was able to erode headward, and the northeast-oriented Belle Fourche River valley eroded further and further south and southwest capturing floodwaters from southeast-oriented flood flow routes that were subsequently beheaded and captured by Little Missouri River valley headward erosion. Evidence to support this interpretation includes not only the southeast-orientation of Belle Fourche River tributaries flowing from the Little Missouri River-Belle Fourche River drainage divide, but also through valleys at the heads of those southeast-oriented tributary valleys documenting that Little Missouri River valley headward erosion beheaded multiple southeast-oriented flood flow routes that had been carrying water to the northeast-oriented Belle Fourche River valley. Flood waters that did reach the newly eroded northeast-oriented Belle Fourche valley moved northeast to the Belle Fourche River elbow of capture where for a time most of the flood waters flowed northwest to the northeast-oriented Little Missouri River, but some of flood water flowed southeast along the original southeast-oriented flood flow route. For reasons not evident in the evidence presented here the original southeast-oriented flood flow route eroded a slightly deeper valley and became the surviving Belle Fourche River route when headward erosion of the Little Missouri and Little Powder River valleys beheaded all southeast-oriented flood flow routes flowing to the newly formed Belle Fourche River drainage basin.

Little Missouri River-Deer Creek drainage divide

Figure 4: Little Missouri River-Deer Creek drainage divide. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 4 shows the Little Missouri River-Belle Fourche River drainage divide area a short distance southwest of the figure 3 map area (there is some overlap). Note how most Little Missouri River tributaries flow in a northwest-oriented direction from the drainage divide area to join the northeast-oriented Little Missouri River. Also, note how most Belle Fourche River tributaries flowing from the drainage divide area flow in a southeast-oriented direction, or at least have southeast-oriented valley segments. Further note how heads of the northwest-oriented Little Missouri River tributaries are linked by through valleys with the heads of the southeast-oriented Belle Fourche River tributaries. These through valleys are better seen on more detailed topographic maps, but evidence can be seen on figure 4 especially at the head of Seely Fork (Deer Creek), which is linked to the head of northwest-oriented Tie Creek and at the head of North Fork (Deer Creek), which is linked to the head of a northwest-oriented Tie Creek tributary. The multiple through valleys are evidence southeast-oriented flood waters flowed across the drainage divide to the newly eroded northeast-oriented Belle Fourche River valley prior to headward erosion of the northeast-oriented Little Missouri River valley. The depth of the present day Belle Fourche River and Little Missouri River valleys provides a measure of amount of flood related erosion that occurred and provides clues as to the volumes of flood waters involved.

Elkhorn Creek-Barnard Creek drainage divide area

Figure 5: Elkhorn Creek-Barnard Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 5 illustrates a Little Missouri River-Belle Fourche River drainage divide immediately southwest of the figure 4 map area (again with some overlap). Again Belle Fourche River tributaries flowing from the Little Missouri River-Belle Fourche River drainage divide area are predominantly southeast-oriented, although Little Missouri River tributaries flowing from the drainage divide frequently have significant northeast and/or north oriented segments as well as northwest-oriented segments. The northeast and north-oriented Little Missouri River tributary segments developed when reversed flood flow on the northwest ends of southeast-oriented flood flow routes beheaded by headward erosion of the deep Little Missouri River valley captured southeast-oriented flood water from yet to be beheaded flood flow further to the southwest. Also, underlying bedrock characteristics probably influenced where valleys were eroded headward. Through valleys cross the drainage divide and connect headwaters of all Belle Fourche River tributaries with headwaters of Little Missouri River tributaries. Again these multiple through valleys are evidence southeast-oriented flood water flowed across what is today the Little Missouri River-Belle Fourche River drainage divide area prior to Little Missouri River valley headward erosion. For example, note Elkhorn Creek flowing north-northeast and north to the Little Missouri River and Barnard Creek flowing southeast and east to the Belle Fourche River valley. The detailed figure 6 map below will illustrate through valleys connecting those two tributary drainage basins.

Detailed map of Elkhorn Creek-Barnard Creek drainage divide

Figure 6: Detailed map of Elkhorn Creek-Barnard Creek drainage divide. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 6 provides a detailed map of some through valleys linking the southeast-oriented Barnard Creek drainage basin with the north oriented Elkhorn Creek drainage basin. Along the figure 6 south edge Barnard Creek flows in a northeast direction and then at its confluence with a southeast-oriented tributary turns southeast to eventually reach the northeast-oriented Belle Fourche River. Elkhorn Creek flows north-northeast in the figure 6 northwest quadrant and a north and northwest-oriented Elkhorn Creek tributary is located in the figure 6 north center (immediately north of the previously mentioned southeast-oriented Barnard Creek tributary). A south to north oriented through valley links the southeast-oriented Barnard Creek tributary with the north and northwest-oriented Elkhorn Creek tributary. Southwest of the figure 6 map area the northeast-oriented Barnard Creek headwaters are linked by a through valley with a northwest-oriented Little Missouri River tributary (see word “Creek in southwest corner figure 5) and the north-northeast-oriented Elkhorn Creek headwaters are linked by through valleys with T L Creek headwaters, which flow north-northwest to the Little Missouri River (see figure 5). North of the figure 6 map area Elkhorn Creek turns north and north-northwest to flow to the Little Missouri River. What has happened is after headward erosion of the Little Missouri River valley had beheaded southeast-oriented flood flow along a southeast-oriented flood flow alignment corresponding with the present day Elkhorn Creek-Little Missouri River confluence location, reversed flood flow to the Little Missouri River valley captured southeast-oriented flood flow still moving across the present day drainage divide area on yet to be beheaded flood flow routes further to the southwest. The north-northeast-oriented Elkhorn Creek valley was eroded by flood waters captured from several of these flood flow routes while the northeast-oriented Barnard Creek headwaters valley and the previously mentioned south to north through valley and the north- and northwest-oriented Elkhorn Creek tributary captured yet to be beheaded southeast-oriented flood waters from a flood flow moving still further to the southwest. In other words, anastomosing channels of southeast-oriented flood flow were being captured by anastomosing channels of north- and northeast-oriented flood flow. Further complicating the situation floodwaters were spilling into the Belle Fourche River valley and  eroding tributary valleys headward from that valley (e. g. the southeast-oriented Barnard Creek was eroded headward to capture flood waters going north to the north- and northwest-oriented Elkhorn Creek tributary).

Drainage divides in Missouri Buttes-Devils Tower area

Figure 7: Drainage divides in Missouri Buttes-Devils Tower area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Continuing southwest from the figure 5 map area figure 7 illustrates the Missouri Buttes and Devils Tower region of the Little Missouri River-Belle Fourche River drainage divide area. Devils Tower and Missouri Buttes are residuals composed of rock types more resistant to erosion than surrounding rock types and today provide a minimum measure of the amount of the removed material as the regional landscape was lowered. While drainage patterns in the Little Missouri River-Belle River drainage divide area are more complicated, the northwest-southeast drainage alignment can still be observed. In the figure 7 northeast corner the southeast-oriented stream flowing to Barlow Creek is Barnard Creek. Note how east-oriented Barlow Creek headwaters are linked by a through valley to the headwaters of (unnamed in figure 7) northwest-oriented Poison Creek. Further south, in the Missouri Butte area, note the maze of north-south oriented through valleys linking southeast-oriented Lake Creek headwaters with Barlow Creek tributaries and with northwest-oriented Little Missouri River tributaries. Many of these through valleys were carved by southeast-oriented flood water flowing on yet to be beheaded (by Little Missouri River valley headward erosion) flood flow routes that were captured and diverted north and then northwest to the reversed flow routes carrying flood water to the deep and actively eroding Little Missouri River valley. These flood flow routes were constantly changing and included routes used by flood waters spilling into what was then also the newly eroded Belle Fourche River valley. In figure 7 south center note southeast-oriented Left Creek and its south-southeast oriented tributary, Right Creek. Figure 8 will provide a detailed map focusing on through valleys associated with the Left and Right Creek valleys.

Detailed map of Little Missouri drainage divide with Left and Right Creeks

Figure 8: Detailed map of Little Missouri River drainage divide with Left and Right Creeks. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 8 provides a detailed map of the Left and Right Creeks drainage areas. Left Creek flows southeast to the northeast oriented Belle Fourche River. Right Creek headwaters are linked by a through valley with northwest-oriented Little Missouri River tributaries (figure 8 north center). This evidence demonstrates that prior to Little Missouri River valley headward erosion flood water moved southeast on the Right Creek-Left Creek alignment to what was then the newly eroded northeast oriented Belle Fourche River valley. Left Creek headwaters from the Basin Reservoir no. 1 area are also connected by through valleys with northwest-oriented Little Missouri River tributaries, but the water movement patterns were probably more complicated. A better understanding comes by looking at the north-northwest oriented Left Creek tributary southeast of the Basin Reservoir no. 1 area (figure 8 south center also see figure 9 below). This tributary flows north-northwest in a well-defined valley that is linked with south-oriented Lawrence Creek, which flows to northeast and southeast oriented Cabin Creek, which flows to the north-northeast-oriented Belle Fourche River (see figure 9 below). Apparently when Little Missouri River valley headward erosion beheaded southeast-oriented flood flow routes flowing directly to the Right Creek and the more northern Left Creek drainage basins, reversed flood flow on those routes as well as the southeast-oriented Left Creek route captured yet to be beheaded flood water moving on southeast-oriented routes further to the southwest and some of that captured flood water moved north through the Lawrence Creek and north-oriented Left Creek tributary route and then flood flow routes went either left along the reversed northwest-oriented flood flow routes or right along the southeast-oriented Left Creek route. Larger mosaics of the detailed maps can be used to further work out details if desired.

Little Missouri River-Belle Fourche River drainage divide at Cabin Creek

Figure 9: Little Missouri River-Belle Fourche River drainage divide at Cabin Creek. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 9 illustrates the Little Missouri River-Belle Fourche River drainage divide near its southwest end. East, northeast and southeast-oriented Cabin Creek flows to the north-northeast-oriented Belle Fourche River. The northeast-oriented Little Missouri River flows from near its origin at the figure 9 west edge across the figure 9 northwest corner. The north-northeast-oriented Belle Fourche River valley is located along the figure 9 east edge and continues a significant distance further south from the figure 9 map area. Note the previously discussed Left Creek-Right Creek drainage area in the figure 9 north center. This is as far southwest as the Little Missouri River valley eroded (figure 10 will show the actual Little Missouri River valley head). Southeast-oriented flood flow to the southeast-oriented North Draw was beheaded and captured by Little Missouri River valley headward erosion. Southeast-oriented flood water to Cabin Creek headwaters west of the figure 9 map area was not beheaded and captured by Little Missouri River valley headward erosion. Instead it was beheaded and captured by Little Powder River valley headward erosion. Figure 9 also provides a big picture view of south to north-oriented through valleys used by southeast-oriented flood waters moving southwest of the Little Missouri River valley that were captured by reversed flow on beheaded flood flow routes and diverted north and northwest to what was then the newly eroded northeast-oriented Little Missouri River valley.

Little Missouri River-Cabin Creek headwaters area

Figure 10 illustrates where the Little Missouri River begins today and the southwest end of Little Missouri River valley headward erosion. Note how the Little Missouri River headwaters actually come from three different northeast-oriented valleys or headcuts, the Deadman Creek valley, the Flag Butte valley, and the Little Missouri River valley. All three dead-end valleys are really abandoned headcuts. Also note southeast-oriented Cabin Creek tributaries flowing from the Flag Butte area and southeast-oriented North Draw flowing from headwaters of northwest-oriented Little Missouri River tributaries. Northwest-oriented streams along the figure 10 west edge are flowing to the north-oriented Little Powder River. Headward erosion of the Little Powder River valley beheaded and captured southeast-oriented flood flow that had been eroding the Little Missouri River valley southwest. The northwest-oriented stream in the figure 10 north center is Prairie Creek, which north of the figure 10 map area turns northeast and flows to the northeast-oriented Little Missouri River. Headward erosion of the northeast-oriented Prairie Creek valley segment beheaded and captured southeast-oriented flood flow that had been moving to what was then the newly eroded Little Missouri River valley. The northwest-oriented Prairie Creek valley segment developed as a reversal of flood flow on the northwest end of a beheaded southeast-oriented flood flow route. Reversed flood water on that route captured southeast-oriented flood water flowing on what is today the northwest-oriented Spring Creek route (named only “Creek” on figure 10, but beginning in the figure 10 center and flowing northwest to the figure 10 northwest corner). Southeast-oriented flood flow on the Spring Creek alignment was beheaded and captured by Little Powder River valley headward erosion and flood water on the northwest end of the beheaded flood flow route reversed flow direction to finalize the Little Powder River River-Little Missouri River drainage divide creation.

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 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.