Abstract:

This essay uses topographic map evidence to interpret landform origins in the region between Nowater Creek and Badwater Creek in the southern Bighorn Basin and Wyoming Bridger Mountains and is located in the region directly east of Wind River Canyon. Nowater Creek flows in a north and northwest direction from the steep Bridger Mountains north flank across the Bighorn Basin floor to join the north oriented Bighorn River. South oriented tributaries flowing from the Bridger Mountains form west oriented Badwater Creek, which joins the north oriented Wind River at the south end of Wind River Canyon. Wind River Canyon is a 900-meter deep canyon eroded across the Owl Creek and Bridger Mountains and the north oriented Wind River, which flows through the Canyon becomes the Bighorn River at the Canyon north end. North-to-south oriented through valleys or passes cross the Bridger Mountains east of Wind River Canyon and link north oriented Bighorn River tributary valleys with south oriented Wind River tributary valleys. Massive south oriented floods are interpreted to have eroded these through valleys. At that time the Bridger Mountains had not emerged and flood water could freely flow across what is today a major mountain barrier. Floodwaters are interpreted to have been derived from the western margin of a thick North American ice sheet and were flowing from western Canada to and across the Bridger Mountain region. As the Bridger Mountains and the Bighorn Basin (to the north) and Wind River Basin (to the south) began to emerge floodwaters were funneled into fewer and fewer south oriented flood flow channels. One such flood flow channel was on the Wind River Canyon alignment. Another long-lasting flood flow channel was on the Nowater Creek-Bridger Creek alignment with Bridger Creek being a south oriented Badwater Creek tributary. A massive flood flow reversal created the north and northwest oriented Nowater Creek drainage route and eroded the Bridger Mountains north-facing escarpment. The flood flow reversal apparently was fed by south oriented flood flow moving into the Wind River Basin from further to the west. Perhaps at the same time or at a later time a massive flood flow reversal also created the north oriented Wind River-Bighorn River through Wind River Canyon and captured significant flood flow from the west that was moving in the present day southeast oriented Wind River valley between the Owl Creek and Wind River Mountains. The flood flow reversal(s) were probably caused by ice sheet related crustal warping and by headward erosion of the deep northeast oriented Yellowstone River valley in Montana. The Yellowstone River valley eroded headward from space in the deep “hole” the melting ice sheet had occupied and that was being opened up as the ice sheet melted. Headward erosion of the deep Yellowstone River valley captured south and southeast oriented flood flow and floodwaters on north ends of the beheaded flood flow routes reversed flow direction to create north oriented drainage routes, such as the north oriented Bighorn River, which then captured floodwaters from further to the west (which were flowing west of the actively eroding Yellowstone River valley head).

Preface

The following interpretation of detailed topographic map evidence is one of a series of essays describing similar evidence for all major drainage divides contained within the Missouri River drainage basin and for all major drainage divides with adjacent drainage basins. The research project is interpreting evidence in the context of a previously unexplored deep glacial erosion paradigm, which is fundamentally different from most commonly accepted North American glacial history interpretations. 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 the Nowater Creek-Badwater Creek drainage divide area landform origins in the southern Bighorn Basin and Wyoming Bridger Mountains. 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 and/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 new geomorphology 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 other Missouri River drainage basin landform origins research project essays is a thick North American ice sheet, comparable in thickness to the Antarctic ice sheet, occupied the North American region usually recognized to have been glaciated, and through its weight and erosive actions created a deep North American “hole”. The southwestern rim of that deep “hole” is today preserved in the high Rocky Mountains. The ice sheet 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 Nowater Creek-Badwater Creek drainage divide area landform evidence in the southern Bighorn Basin and Wyoming Bridger Mountains will be regarded as evidence supporting the “thick ice sheet that melted fast” paradigm.

Nowater Creek-Badwater Creek drainage divide area location map

Figure 1: -Nowater Creek-Badwater Creek drainage divide area 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 location map for the Nowater Creek-Badwater Creek drainage divide area in the southern Bighorn Basin and Wyoming Bridger Mountains and illustrates a region in west-central Wyoming. Casper is the largest city shown and is located in the southeast corner of figure 1. The Owl Creek Mountains are located in the west center region of figure 1 and the Wind River Mountains extend across the southwest corner of figure 1. The Wind River flows in a southeast direction from the west edge of figure 1 (south of center) between the Owl Creek and Wind River Mountains to Riverton and then turns to flow in a northeast and north direction to Boysen Reservoir. From Boysen Reservoir the Wind River flows through Wind River Canyon (unlabeled in figure 1, but a deep canyon eroded across the Owl Creek Mountains) to near Thermopolis where the river name changes to become the Bighorn River. From Thermopolis the Bighorn River flows in a north direction to the north edge of figure 1. North of figure 1 the Bighorn River flows in a north and north-northeast direction into Montana to join the northeast oriented Yellowstone River. The Bridger Mountains are the mountains directly east of Wind River Canyon and link the Owl Creek Mountains with the Bighorn Mountains, which extend in a north-to-south direction from the north edge of figure 1 (east of the Bighorn River). The southern Bighorn Basin as seen in figure 1 is north of the Owl Creek and Bridger Mountains and west of the Bighorn Mountains. The Wind River Basin is located south of the Owl Creek Mountains and north and east of the Wind River Mountains. Nowater Creek is a north and northwest oriented stream in the southern Bighorn Basin originating near the center of figure 1 and joining the Bighorn River south of Worland. The west oriented stream flowing from Lyesite to Boysen Reservoir is Badwater Creek and is located on the south side of the Bridger Mountains. The unnamed south oriented stream originating near the Nowater Creek headwaters and flowing to Badwater Creek near Lyesite is Bridger Creek and originates on the Bridger Mountains north side and flows across the Bridger Mountains to the Badwater Creek drainage route on the south side. The Nowater Creek-Badwater Creek drainage divide area investigated in this essay is located east of the Wind-Bighorn River, north of Badwater Creek, west of Bridger Creek, and south and west of Nowater Creek.

Prior to development of present day drainage routes the region seen in figure 1 was crossed by immense south and southeast oriented floods. Floodwaters were derived from the western margin of a thick North American ice sheet and were flowing from western Canada to and across the region in figure 1. Initially mountain ranges and basins seen in figure 1 (and elsewhere) had not emerged and floodwaters could flow across what are today major topographic barriers. The mountain ranges and basins emerged as the floodwaters flowed across the region and as deep valleys eroded headward into the region to capture the south and southeast oriented flood flow. Deep glacial erosion under the ice sheet combined with ice sheet related crustal warping created a deep “hole” in which the ice sheet was located and raised mountain ranges in the figure 1 region, which was located along the deep “hole’s” southwest rim as floodwaters flowed across the region. At first south and southeast oriented floodwaters entering what is now the Bighorn Basin flowed on an erosion surface at least as high as the top of the Owl Creek and Bridger Mountains (which may have been uplifted since) into the Wind River Basin and then in a south and southeast direction across Wyoming. As the Owl Creek and Bridger Mountains emerged floodwaters were funneled into fewer and fewer flood flow channels, which eroded deeper and deeper valleys into the emerging mountains. One such south oriented flood flow channel was on the Nowater Creek-Bridger Creek alignment while another such flood flow channel was on the present day north oriented Wind River Canyon alignment (these two flood flow channels may have diverged from each other in the Bighorn Basin and may have converged in the Wind River Basin area). Headward erosion of the deep northeast oriented Yellowstone River valley in Montana (from space in the deep “hole” being opened up by ice sheet melting) beheaded south oriented flood flow channesl supplying floodwaters to the eastern Bighorn Basin and a massive flood flow reversal was initiated. Floodwaters on north ends of beheaded flood flow channels reversed flow direction in sequence from east to west to create the north oriented Bighorn River drainage route, which in turn reversed flow on the north and northwest end of the Nowater Creek-Bridger Creek flood flow channel to create the north and northwest oriented Nowater Creek drainage route, which probably for a time captured south and southeast oriented flood flow moving into the Wind River Basin. The newly reversed flood flow channel on the Bighorn River-Wind River Canyon alignment then captured southeast oriented flood flow moving into the Wind River from west of the actively eroding Yellowstone River valley head. This southeast oriented flood flow then moved in a north direction through Wind River Canyon and eroded the Wind River and Bighorn Basins deeper as the Wind River Canyon depth was also deepened. In time Yellowstone River valley headward erosion beheaded all south and southeast oriented flood flow routes to the region seen in figure 1.

Detailed location map for Nowater Creek-Badwater Creek drainage divide area

Figure 2: Detailed location map Nowater Creek-Badwater Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 2 provides a more detailed location map for the Nowater Creek-Badwater Creek drainage divide area in the southern Bighorn Basin and Wyoming Bridger Mountains. Boysen Reservoir is located near the southwest corner of figure 2. The brown colored region straddling the west edge of figure 2 is Wind River Indian Reservation land. The Wind River flows through Wind River Canyon to Thermopolis where the river name changes to become the Bighorn River. The Bighorn River then flows in a north and northeast direction to the north edge of figure 2. The Bridger Mountains are located east of Wind River Canyon and Copper Mountain is a high mountain near the Bridger Mountains center. West oriented streams joining the north oriented Bighorn River north of Wind River Canyon include Buffalo Creek and Kirby Creek, although they also have north or north-northwest oriented headwaters or tributaries. Lyesite Mountain is located east of the Bridger Mountains and further east is the Bighorn Mountains south end. Grass Creek is a north-northwest oriented Buffalo Creek tributary and Kirby Creek begins as a north-northwest oriented stream west of Klondike Peak. Mud Creek is a north-northwest oriented Nowater Creek tributary located north of Klondike Peak. East of Klondike Peak are headwaters of north, northwest, and north-northwest oriented Nowater Creek, which flows to the north edge of figure 2 (east half) and which joins the Bighorn River north of figure 2. Lyesite is a small town located near the south center edge of figure 2 and Badwater Creek flows in a west direction from Lyesite to join the north oriented Wind River at Boysen Reservoir. Note south oriented streams flowing from the Copper Mountain area to join west oriented Badwater Creek and also to join the north oriented Wind River as barbed tributaries. Bridger Creek originates north of Lyesite Mountain and flows in a north-northwest, southwest, south-southeast, and south direction to join Badwater Creek near the town of Lyesite. Many south oriented Badwater Creek tributaries are aligned with north and north-northwest oriented streams flowing to Buffalo Creek, Kirby Creek, or Nowater Creek. Topographic maps shown below illustrate passes or through valleys linking these opposing drainage routes, which are on the alignments of former south oriented flood flow channels that once crossed the region. At that time there was no deep Wind River Canyon and the Bridger Range and other regional mountains had not emerged so floodwaters could freely flow across what are today a major topographic barriers. The Bridger Creek headwaters are located north of the headwaters of most of the south oriented Badwater Creek tributaries.

Grass Creek-Birdseye Creek drainage divide area near Wind River Canyon

Figure 3: Grass Creek-Birdseye Creek drainage divide area near Wind River Canyon. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 3 provides a topographic map of the Grass Creek-Birdseye Creek drainage divide area near Wind River Canyon. The yellows colored region is Wind River Indian Reservation land. Boysen Reservoir straddles the south edge of figure 3 near the southwest corner. The Wind River flows in a north direction from Boysen Reservoir through Wind River Canyon to the north edge of figure 3. The map contour interval for figure 3 is 20 meters except near the north edge where the contour interval is 50 meters. Boysen Peak in the Owl Creek Mountains near the west center edge of figure 3 reaches an elevation of more than 2300 meters. Elevations on Copper Mountain to the east rise to more than 2500 meters. The normal pool elevation at Boysen Reservoir is 1440 meters and elevations on the floor of Wind River Canyon decrease in a north direction. These elevations suggest Wind River Canyon is approximately 900 meters deep as it cuts across the Owl Creek and Bridger Mountains. Birdseye Pass is located near the center of figure 3. Grass Creek originates on Copper Mountain east of Birdseye Pass and flows in a north-northwest direction to the north edge of figure 3 (west of center). North of figure 3 Grass Creek joins west oriented Buffalo Creek, which flows to the north oriented Wind (Bighorn) River. The south oriented stream originating near Birdseye Pass is Birdseye Creek, which flows in a south and southwest direction to the south edge of figure 3 (west of center) and south of figure 3 flows to Boysen Reservoir as a barbed tributary. The Birdseye Pass elevation is between 2120 and 2140 meters. Birdseye Mountain to the west rises to at least 2260 meters while Copper Mountain to the east rises much higher. These elevations suggest Birdseye Pass is approximately 120 meters deep. Compared to the depth of nearby Wind River Canyon the Birdseye Pass depth is small, however Birdseye Pass is evidence of a south oriented flood flow channel that once crossed the region. At that time the Owl Creek Mountains and Bridger Mountains had not emerged as the topographic barriers they are today and floodwaters were flowing on an erosion surface at least as high as a surface defined by the Birdseye Pass elevation and perhaps as high as tops of Boysen Peak and Birdseye Mountain (if not higher). Floodwaters were converging in the Wind River Basin to the south of figure 3 and then flowing in south and/or southeast directions across central Wyoming. As the Owl Creek and Bridger Mountains emerged the south oriented flood flow channels eroded deeper and deeper valleys into the emerging mountain mass. The south oriented valley on the Wind River Canyon alignment was able to erode its valley much deeper and over time captured flood flow from adjacent flood flow channels, such as the flood flow that had been eroding the Birdseye Pass valley. Floodwaters on the north-northwest end of the beheaded Birdseye Pass flood flow channel then reversed flow direction to create the north-northwest oriented Grass Creek drainage route. Subsequently flood flow in the Wind River Canyon valley was reversed to flow in a north direction to the much deeper northeast oriented Yellowstone River valley, which had eroded headward from space in the deep “hole” the melting ice sheet had occupied and was opening up. Large volumes of south and southeast oriented flood flow from west of the actively eroding Yellowstone River valley head continued to flow into the emerging Wind River Basin and was captured so as to flow in a north direction through Wind River Canyon. This captured flood flow eroded the Wind River Basin and Wind River Canyon much deeper than they had been at the time of the flood flow reversal.

Detailed map of Grass Creek-Birdseye Creek drainage divide area

Figure 4: Detailed map of Grass Creek-Birdseye Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 4 provides a detailed topographic map of the Grass Creek-Birdseye Creek drainage divide seen in less detail in figure 3. The map contour interval for figure 4 is 20 feet. Birdseye Pass is located near the center of figure 4. West of Birdseye Pass is Birdseye Mountain, which reaches an elevation of 7514 feet. East of Birdseye Pass is Copper Mountain, which in figure 4 reaches an elevation of 8053 feet. The Birdseye Pass elevation is shown as 6993 feet suggesting Birdseye Pass is at least 500 feet deep. Birdseye Creek originates in section 11 on the south side of Birdseye Pass and flows in a southwest and south direction to the south edge of figure 4. South of figure 4 Birdseye Creek flows to the north oriented Wind (Bighorn) River as a barbed tributary. Grass Creek originates in section 7 east of Birdseye Pass and flows in a northwest and north-northwest direction to the north center edge of figure 4. North of figure 4 Grass Creek flows to west oriented Buffalo Creek, which then flows to the north oriented Bighorn (Wind) River.  Note how the north oriented Grass Creek valley and the south oriented Birdseye Creek valley are linked by a through valley at Birdseye Pass. A south oriented flood flow channel eroded the Birdseye Pass through valley at a time when the surface north of Birdseye Pass was at least as high as Birdseye Pass. Floodwaters were flowing from the present day Bighorn Basin into what was at that time the actively eroding Wind River Basin to the south. At that time the Bighorn Basin to the north was only beginning to be eroded and the deep Wind River Canyon valley to the west of figure 4 did not yet exist. Erosion of a deeper south oriented flood flow channel on the Wind River Canyon alignment resulted in headward erosion of the west oriented Buffalo Creek valley (north of figure 4), which beheaded the south oriented flood flow channel eroding the Birdseye Pass valley. Floodwaters on the north end of the beheaded flood flow channel reversed flow direction to establish the north-northwest oriented Grass Creek drainage route.

Kirby Creek-Bridger Creek drainage divide area

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

Figure 5 provides a topographic map to illustrate the Kirby Creek-Bridger Creek drainage divide area north and east of figure 3 and includes an overlap area with figure 3. Klondike Peak is located near the northeast corner of figure 5 and Lyesite Mountain is located along the east edge of figure 5. Bridger Creek flows in a southwest, south, and south-southeast direction from the east edge of figure 5 (near northeast corner) between Klondike Peak and Lyesite Mountain to the south edge of figure 5 (east half) and south of figure 5 joins west oriented Badwater Creek. South and west of figure 5 Badwater Creek joins the north oriented Wind (Bighorn) River. Copper Mountain is located near the southwest corner of figure 5. The East Fork West Bridger Creek originates near Copper Mountain and flows in a northeast and east-southeast direction to join Bridger Creek in the southeast quadrant of figure 5. Hall Butte in a high point located north of the center of figure 5. East Kirby Creek originates south and east of Hall Butte and flows in a north-northwest direction to the north edge of figure 5 (slightly east of center). North of figure 5 Kirby Creek flows in a north-northwest and west direction to join the north oriented Bighorn (Wind) River. Little V-H Draw is a southwest oriented (and barbed) tributary to north-northwest oriented East Kirby Creek. A pipeline follows the East Kirby Creek valley and then continues in a south direction to the Bridger Creek valley. That pipeline is following the deepest section of what is a large north-to-south oriented through valley linking the north oriented East Kirby Creek valley and the south oriented Bridger Creek valley. The map contour interval for figure 5 is 20 meters and the elevation where the pipeline crosses the drainage divide is between 1900 and 1920 meters. Elevations on Klondike Peak reach 2189 meters with slightly lower elevations seen on Lyesite Mountain to the south. Copper Mountain to the southwest rises much higher suggesting the Kirby Creek-Bridger Creek through valley is approximately 160 meters deep. The through valley was eroded by a large south oriented flood flow channel that was able to erode a much deeper valley than the Birdseye Pass through valley seen in figures 3 and 4. However, in time headward erosion of the west oriented Kirby Creek valley north of figure 5 beheaded the south oriented flood flow channel to the Kirby Creek-Bridger Creek through valley. Floodwaters on the north end of the beheaded flood flow channel reversed flow direction to create the north-northwest oriented Kirby Creek headwaters drainage route and probably captured significant floodwaters flowing into the Wind River Basin from further to the west.

Nowater Creek-Bridger Creek drainage divide area

Figure 6: Nowater Creek-Bridger Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 6 illustrates the Nowater Creek-Bridger Creek drainage divide area north and east of figure 5 and includes an overlap area with figure 5. Klondike Peak is located in the southwest quadrant of figure 6. Lyesite Mountain is the “Mountain” located south and east of Klondike Peak. Bridger Creek originates north of Lysite Mountain and flows in a north direction before turning to flow in a southwest direction to the southwest corner of figure 6. South of figure 6 Bridger Creek flows to west oriented Badwater Creek, which then flows to the north oriented Wind (Bighorn) River. Hawks Butte is located in the south center region of figure 6. Nowater Creek originates just west of Hawks Butte and flows in a north and north-northwest direction to the north edge of figure 6 (slightly west of center). North of figure 6 Nowater Creek flows in a northwest direction to reach the north oriented Bighorn (Wind) River. The unnamed south oriented stream flowing to the south edge of figure 6 (west of center and south of the Nowater Creek headwaters) is Lysite Creek, which south of figure 6 joins Bridger Creek. South of Hawks Butte and just west of Battle Mountain are headwaters of south and east-northeast oriented Bates Creek, which flows to the northeast oriented Nowood River headwaters. East of figure 6 the Nowood River turns to flow in a north and northwest direction to eventually join the Bighorn (Wind) River. West of Hawks Butte the Nowater Creek headwaters are located in a north oriented escarpment surrounded basin. The north oriented escarpment surrounded basin may be an abandoned headcut eroded by a massive flood flow reversal when floodwaters on Nowater Creek alignment were beheaded and reversed. If so the reversed flood flow from the present day Wind River Basin area moved in a north direction across Lyesite Mountain. If this interpretation is correct a look at the through valley just west of Hawks Butte is merited. The through valley links the north oriented Nowater Creek valley with the south oriented Bates Creek headwaters valley and probably originated as a south oriented flood flow channel route. The map contour interval for figure 6 is 20 meters and the through valley elevation is between 2020 and 2040 meters. Hawks Butte rises to 2157 meters and Lysite Mountain to the west rises to more than 2160 meters suggesting the through valley is approximately 120 meters deep. There is a much steeper gradient to the north suggesting the final flood flow movement was in a north direction and that large volumes of water eroded the north oriented Nowater Creek valley head. If so the floodwaters may have moved in a southeast and south direction on the Nowood River alignment although other interpretations are possible.

Detailed map of Nowater Creek-Bates Creek drainage divide area

Figure 7: Detailed map of Nowater Creek-Bates Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 7 provides a detailed topographic map of the Nowater Creek-Bates Creek drainage divide area and seen in less detail in figure 6. The map contour interval for figure 7 is 20 feet. North-northwest oriented Bridger Creek headwaters can be seen along the west center edge of figure 7. West of figure 7 Bridger Creek turns to flow in a southwest and south direction to eventually join west oriented Badwater Creek. Hawks Butte is located in section 36 (east of center) and reaches an elevation of 7060 feet. Battle Mountain is south of Hawks Butte. Bates Creek originates in section 2 (west of Battle Mountain) and flows in a northeast direction into section 35 (west of Hawks Butte) and then turns to flow in a south direction along the west side of Battle Mountain to the south edge of figure 7. As seen in figure 6 south of figure 7 Bates Creek turns to flow in an east-northeast direction to join the northeast oriented Nowood River headwaters with the Nowood River eventually turning to flow to a north and northwest direction to join the north oriented Bighorn River. Nowater Creek originates along the boundary between sections 2  and 3 and flows in a north-northeast direction into section 35 and then makes a short eastward jog before turning to flow in a north direction to the north center edge of figure 7. North of figure 7 Nowater Creek turns to flow in a northwest direction to the north oriented Bighorn River. West of Hawks Butte there is a steep north-facing escarpment, which suggests it might be a north-facing abandoned headcut eroded by north oriented floodwaters. Based on the figure 6 discussion the hypothesis was presented that the floodwaters moved south on the Nowwod River alignment (east of figure 7) and then made a U-turn to flow in a north direction on the newly reversed Nowater Creek alignment. While this hypothesis requires some complex flood flow movements it would account for the deep erosion in the Nowater Creek headwaters region. The through valley linking the north oriented Nowater Creek valley with the south oriented Bates Creek valley is near the east center edge of section 35. The through valley floor elevation is between 6660 and 6680 feet with elevations on Hawks Butte reaching 7060 feet and in the southeast corner of section 3 greater than 7080 feet. These elevations suggest the pass is at least 380 feet deep. The pass is a water-eroded valley and while the region was crossed by south oriented flood flow, the final flood flow movement through the pass may have been in a north direction.

Nowater Creek-Sand Draw drainage divide area

Figure 8: Nowater Creek-Sand Draw drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 8 provides a topographic map of the Nowater Creek-Sand Draw drainage divide area north of figure 3 and there is no overlap with previous figures. The Bighorn River flows in a north and northeast direction from the south edge of figure 8 (west half)) to the north center edge of figure 8. Sand Draw is a south and southwest oriented tributary draining to the south edge of figure 8 (west half) and joining the north oriented Bighorn River as a barbed tributary south of figure 8. Nowater Creek flows in a north-northwest direction across the northeast corner of figure 8 and joins the Bighorn River north of figure 8. Note north oriented Bighorn River and Nowater Creek tributaries in the north half of figure 8, including Neiber Draw, Wildcat Gulch, and Pistol Draw. These drainage routes originate just north of the south oriented Sand Draw headwaters with the drainage divide being located near the county line. The map contour interval for figure 8 is 20 meters in the west and 50 meters in the west. For a considerable distance the drainage divide elevation is between 1500 and 1520 meters. Zimmerman Buttes near the south edge of the southeast quadrant of figure 8 reaches an elevation of 1595 meters. Cedar Mountain in the southwest quadrant of figure 8 has an elevation of more than 1650 meters. These elevations suggest there is a broad northeast-to-southwest oriented through valley linking the northeast oriented drainage routes with the south and southwest oriented Sand Draw drainage route. The through valley was probably initially eroded by southwest oriented flood flow moving to a south oriented flood flow channel on the present day north oriented Bighorn River alignment. The south oriented flood flow was moving to the deep south-oriented flood flow channel on the present day north oriented Wind River Canyon alignment. Headward erosion of a deeper north and north-northwest oriented Nowater Creek valley during the massive Bighorn Basin flood flow reversal beheaded the southwest oriented flood flow channel to the southwest oriented Sand Draw valley. Floodwaters on the northeast end of the beheaded flood flow channel reversed flow direction to create the northeast oriented drainage routes. Subsequently south oriented flood flow on the Bighorn River alignment was beheaded and reversed to create the north oriented Bighorn River drainage system seen in figure 8.

Nowater Creek-Kirby Creek drainage divide area

Figure 9: Nowater Creek-Kirby Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 9 provides a topographic map of the Nowater Creek-Kirby Creek drainage divide area south and east of figure 8 and includes an overlap area with figure 8 and is also north and west of figure 6 and includes an overlap area with figure 6. Zimmerman Buttes is located near the northwest corner of figure 9. Kirby Creek flows in a north-northwest and west-northwest direction from the south edge of figure 9 (west of center) to the west edge of figure 9 (north of center). Black Mountain is located near the southeast corner of figure 9 and Lake Creek Divide is east of Black Mountain. Lake Creek is a northwest oriented Kirby Creek tributary flowing along the southwest side of Lake Creek Divide. Nowater Creek flows in a northwest direction across the northeast corner of figure 9. Mud Creek is a northwest, north, northwest, and north oriented stream flowing between Black Mountain and Lake Creek Divide to the north center edge of figure 9 and north of figure 9 joining Nowater Creek. The map contour interval for figure 9 is 20 meters. Zimmerman Buttes reaches an elevation of 1595 meters and Black Mountain reaches an elevation of 1896 meters. Elevations on Lake Creek Divide exceed 1600 meters. Between Zimmerman Buttes and Lake Creek Divide elevations are generally less than 1500 meters and in places are less than 1460 meters. Note the north and north-northeast oriented Nowater Creek tributaries flowing to the north edge of figure 9. Packsaddle Creek is a south oriented tributary flowing to northwest oriented Lake Creek as a barbed tributary. The lower elevations between Zimmerman Buttes and Lake Creek Divide are evidence of a broad north-to-south oriented through valley crossing the region. The width of the through valley suggests floodwaters eroded the Bighorn Basin surface by stripping broad swaths of surface material. In tis case approximately 100 meters of surface bedrock was removed with the final flood flow movement probably being in a north direction to the newly reversed Nowater Creek valley. The evidence seen in figure 9 suggests there was significant north movement of floodwaters following the reversal of flood flow in the Nowater and Kirby Creek drainage basins.

Nowood River-Badwater Creek drainage divide area

Figure 10: Nowood River-Badwater Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 10 provides a topographic map of the Nowood River-Badwater Creek drainage divide area south and east of figure 5 and includes a small overlap area with figure 5. We are now in the region between the Bridger Mountains and the Bighorn Mountains. Lyestite Mountain straddles the west center edge of figure 10 and Lyesite Creek flows in a south direction from north of figure 10 (west half) across Lyesite Mountain to the south edge of figure 10 (near southwest corner) and south of figure 10 joins west oriented Badwater Creek. Cottonwood Creek originates near Cottonwood Pass and flows in a south-southwest direction to the south edge of figure 10 (west half). Sioux Creek originates near Sioux Pass (in east center area of figure 10) and flows in a southwest and south-southwest direction to the south center edge of figure 10. South of figure 10 Cottonwood Creek and Sioux Creek flow to west oriented Badwater Creek. Trout Creek is the north oriented stream north of Sioux Pass and north of figure 10 flows to the north and northwest oriented Nowood River. Stove Creek is the north-northeast oriented stream north of Cottonwood Pass and north of figure 10 Stove Creek flows to the northeast oriented Nowood River headwaters, which turn to flow in a north direction further east where joined by north oriented Trout Creek. The map contour interval for figure 10 is 20 meters and the Cottonwood Pass elevation is 2050 meters while the Sioux Pass elevation is 2170 meters. Elevations immediately west of Sioux Pass rise to more than 2380 meters and rise even higher to the east. As seen in earlier figures elevations on Copper Mountain to the west rise to 2482 meters. These elevations suggest Sioux Pass is at least 200 meters deep and Cottonwood Pass when viewed as a deep channel in a broad through valley could be more than 300 meters deep. These passes were eroded by south oriented flood flow moving from the present day north oriented Nowood River drainage route, although it is possible the final flood flow movements were in a north direction. These passes will be looked at again in the Nowood River-Badwater Creek drainage divide area in the southern Bighorn Mountain essay.

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.