Abstract:

This essay uses topographic map evidence to interpret landform origins in the region between Goose Creek and Piney Creek in the Wyoming Bighorn Mountains. Big and Little Goose Creek headwaters originate north of north-to-south oriented passes across the high Bighorn Mountains and flow in north directions to converge east of the Bighorn Mountains and to form north oriented Goose Creek, which then flows to the northeast oriented Tongue River. South Piney Creek headwaters are located south of the Little Goose Creek headwaters and flow in a north-northeast direction to converge with north-northeast oriented North Piney Creek at the Bighorn Mountains base and to form southeast oriented Piney Creek, which joins northeast oriented Clear Creek, which then flows to the north oriented Powder River. Through valleys link the Little Goose Creek and North Piney Creek valleys, the North Piney Creek and South Piney Creek valleys, and the Little Goose Creek and South Piney Creek valleys.  The through valleys are interpreted to have been eroded as south oriented flood flow channels at a time when the Bighorn Mountains did not stand high above surrounding regions as they do today. 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 Bighorn Mountains region. Present day north oriented Goose Creek and Piney Creek tributary and headwaters valleys probably originated as flood flow channels moving floodwaters to deeper flood flow channels south and west of the emerging Bighorn Mountains. Headward erosion of a deep southeast and east oriented valley along the southeast oriented Piney Creek alignment (and east of the emerging Bighorn Mountains) beheaded and reversed flood flow channels on the South and North Piney Creek alignments and captured south oriented flood flow still moving on the Little Goose Creek alignment to create the north-northeast oriented North and South Piney Creek drainage routes. Headward erosion of the deep northeast oriented Tongue River-Yellowstone River valley from space in the deep “hole” the melting ice sheet had occupied next beheaded and reversed flood flow on flood flow channels diverging from the north oriented Goose Creek alignment and created the north oriented Little and Big Goose Creek drainage systems. Bighorn Mountains emergence occurred as floodwaters deeply eroded surrounding regions and as ice sheet related crustal warping created a southwest rim for the deep “hole” in which the ice sheet was located. Alpine glaciation in the high Bighorn Mountains occurred after the Bighorn Mountains had emerged as a high mountain range and was not associated with the thick North American ice sheet or related floodwaters responsible for emergence of the Bighorn Mountains as a high mountain range.

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 Goose Creek and Piney Creek drainage divide area landform origins in the Wyoming Bighorn Mountains, USA. 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 Goose Creek-Piney Creek drainage divide area landform evidence in the Wyoming Bighorn Mountains will be regarded as evidence supporting the “thick ice sheet that melted fast” paradigm.

Goose Creek-Piney Creek drainage divide area location map

Figure 1: Goose Creek-Piney 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 Goose Creek-Piney Creek drainage divide area in the Wyoming Bighorn Mountains. The west to east oriented Montana-Wyoming state line extends across the north half of figure 1 with Montana north of Wyoming. The Bighorn Mountains extend in a north to south direction across the center of figure 1. The Bighorn Basin is located west of the Bighorn Mountains and the Powder River Basin is located east of the Bighorn Mountains. The Bighorn Basin is drained by the north oriented Bighorn River, which originates as the southeast oriented Wind River (seen in southwest corner of figure 1). The Powder River flows in a north direction in the Powder River Basin before turning near the state line to flow in a northeast direction into Montana and then to the north edge of figure 1 (near northeast corner). North of figure 1 the Powder River flows to the northeast oriented Yellowstone River. Clear Creek is an east and northeast oriented Powder River tributary originating in the Bighorn Mountains and flowing near the towns of Buffalo and Clearmont, Wyoming. Piney Creek is the unlabeled northeast and east oriented Clear Creek tributary flowing near the town of Story, Wyoming. The Tongue River is the east-northeast stream originating in the Bighorn Mountains south of the state line and flowing to the towns of Dayton, Ranchester, and Acme, Wyoming before turning to flow in a northeast direction to Decker, Montana and Tongue River Reservoir and then to the north edge of figure 1. North of figure 1 the Tongue River flows to the northeast oriented Yellowstone River. Goose Creek is the unlabeled north, northeast, and north oriented Tongue River tributary originating in the Bighorn Mountains east of Dome Peak and flowing near Sheridan, Wyoming before joining the Tongue River near Acme, Wyoming. The Goose Creek-Piney Creek drainage divide area investigated in this essay is located in the Bighorn Mountains and is south and east of Goose Creek and north and west of Piney Creek.

Today most drainage routes seen in figure 1 are north oriented or flow to north oriented rivers, although a close look at figure 1 reveals southeast oriented tributaries to the north oriented Bighorn and Powder Rivers. These barbed tributaries are evidence of south and southeast oriented flood flow channels that preceded the present day north oriented drainage systems. The south and southeast oriented floodwaters flowed across the entire region seen in figure 1 and were derived from the western margin of a thick North American ice sheet. Floodwaters were flowing from western Canada to and across the Bighorn Mountains region until Bighorn Mountains emergence forced floodwaters to flow around the Bighorn Mountains. Bighorn Mountains emergence occurred as floodwaters deeply eroded the surrounding region and as ice sheet related crustal warping raised the Bighorn Mountains as floodwaters flowed across them. Ice sheet crustal warping combined with deep glacial erosion underneath the ice sheet created a deep “hole” in which the ice sheet was located. The region seen in figure 1 could be considered to be a segment of the deep “hole’s” southwest rim. As the huge ice sheet melted space at the south end of deep “hole” was opened up and at least initially drained in a south direction using flood flow channels east of figure 1. The deep northeast oriented Yellowstone River valley (north of figure 1) eroded headward across Montana from this newly opened up deep “hole” space to capture the south and southeast oriented melt water floods and to divert the floodwaters in a northeast direction. Yellowstone River valley headward erosion beheaded south and southeast oriented flood flow channels in sequence and floodwaters on north ends of the beheaded flood flow channels reversed flow direction to create north oriented drainage routes. Northeast oriented valleys then eroded headward from these newly formed north oriented drainage routes to capture south and southeast oriented flood flow moving west of the actively eroding Yellowstone River valley head. This process was repeated, although on frequently on much smaller scales, as northeast oriented tributary valleys captured south and southeast oriented flood flow with the ultimate result that large north oriented drainage systems were created. The north oriented Powder River drainage system was created first with the north oriented Tongue River being created next and the north oriented Bighorn River drainage system being created still later on. This systematic and massive reversal of the south and southeast melt water flood flow occurred as the Bighorn Mountains were emerging to become the high mountain range they are today.

Detailed location map for Goose Creek-Piney Creek drainage divide area

Figure 2: Detailed location map Goose Creek-Piney 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 Goose Creek-Piney Creek drainage divide area in the Wyoming Bighorn Mountains. The green colored areas are National Forest lands, which are located in the Bighorn Mountains. The dashed line in the green colored area extending from the west edge of figure 2 (north half) to the south center edge of figure 2 is a county line following the Bighorn Mountains crest and is the divide between drainage to the Bighorn Basin to the west and to the Powder River Basin to the east. Burgess Junction is a labeled highway intersection in the northwest quadrant of figure 2 and the North Tongue River originates west of Burgess Junction (near west edge of figure 2) and flows in a southeast and northeast direction before turning to flow in an east direction to join the northwest and north-northwest oriented South Tongue River and to form the Tongue River, which then flows in a northeast direction to Dayton and the north edge of figure 2 (west of center). Goose Creek is formed near Sheridan at the confluence of north and northeast oriented Big Goose Creek and north-northeast, southeast, and north-northeast oriented Little Goose Creek. Note how north oriented Big Goose Creek headwaters originate along the high Bighorn Mountains crest ridge and are roughly aligned with southwest oriented streams flowing to the south edge of figure 2 (southwest quadrant of figure 2). Clear Creek is the east-northeast oriented stream flowing to Buffalo and then flowing in a north-northeast direction to Ucross before turning to flow in an east direction to the east center edge and east of figure 2 flows to the Powder River. Piney Creek joins Clear Creek at Ucross and is formed south of Banner at the confluence of North and South Piney Creeks. Once formed Piney Creek flows in a southeast, northeast, and east direction to join Clear Creek at Ucross. North Piney Creek flows in a northeast, north, and east direction from the Bighorn Mountains before turning in a southeast direction to join South Piney Creek. South Piney Creek originates in the high Bighorn Mountains and flows in a north-northeast and northeast direction to join southeast oriented North Piney Creek and to form Piney Creek, which then flows in a southeast direction. Kearney Creek is a northeast oriented South Piney Creek tributary located south of the North Piney Creek headwaters. While most streams and stream segments shown in figure 2 are oriented in north directions and all streams shown flow to north oriented rivers a close look at figure 2 shows a number of south oriented streams and/or stream segments. The southeast oriented Piney Creek segment south of Banner would be one example. Other examples are southeast oriented Clear Creek tributaries seen along the east edge of figure 2 and southwest oriented streams flowing to the Bighorn Basin west of the high Bighorn Mountains crest ridge. These south oriented streams provide evidence of one time south oriented flood flow channels that existed prior to the systematic and massive flood flow reversal that created the present day north oriented drainage systems.

Little Goose Creek-North Piney Creek drainage divide area

Figure 3: Little Goose Creek-North Piney Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 3 provides a topographic map of Little Goose Creek-North Piney Creek drainage divide area and is located along Bighorn Mountains eastern flank. Banner is a small town located on the highway just north of the east center edge area of figure 3. Story is a small town located south and west of Banner. North Piney Creek flows in a north-northeast and east direction from the south edge of figure 3 (west half) to near Story where it joins northeast oriented South Piney Creek to form southeast oriented Piney Creek, which then flows to the east edge of figure 3 (south half). South Piney Creek flows in a northeast direction from the south edge of figure 3 (west of center) to join North Piney Creek just east of Story. East of figure 3 Piney Creek flows to Clear Creek, which then flows to the Powder River. The East Fork Little Goose Creek flows in a north-northeast direction from the southwest corner of figure 3 to join the north-northeast oriented West Fork Little Goose Creek and to form Little Goose Creek, which then flows in a north-northeast, southeast, north, and north-northeast direction to the north edge of figure 3 (west of center). Trabing Creek is a north-oriented Little Goose Creek tributary originating near the west end of Moncreiffe Ridge. North of figure 3 Little Goose Creek joins Big Goose Creek to form north oriented Goose Creek, which then flows to the Tongue River. Note how a through valley links the north oriented Trabing Creek valley with the North Piney Creek valley. The map contour interval for figure 3 is 20 meters and the through valley floor elevation is 1930 meters. The ridge directly east of the through valley rises to more than 2060 meters and west of the through valley elevations rise much higher suggesting the through valley is at least 130 meters deep. Other much shallower through valleys can be seen crossing the Little Goose Creek-North Piney Creek drainage divide. These through valleys are evidence of south oriented flood flow channels that once crossed the region. At the time floodwaters flowed in those through valley there was no deep Little Goose Creek valley to the north and elevations north of the through valleys were at least as high as the through valley floor elevations if not higher. Headward erosion of the much deeper northeast oriented Tongue River valley north of figure 3 beheaded the south oriented flood flow channels and floodwaters on the north end of the beheaded flood flow channels reversed flow direction to create the north oriented Little Goose Creek drainage route and its north oriented tributary drainage routes. The reversed flood flow eroded a much deeper valley north of the through valleys and captured southeast oriented flood flow on the southeast oriented Little Goose Creek segment alignment. The much deeper north oriented Little Goose Creek valley head then eroded headward and beheaded south oriented flood flow channels near the west edge of figure 3. Floodwaters on north ends of those beheaded flood flow channels reversed flow direction to created the north oriented East Fork Little Goose Creek and West Fork Little Goose Creek drainage routes seen in figure 3.

Detailed map of Trabing Creek-North Piney Creek drainage divide area

Figure 4: Detailed map of Trabing Creek-North Piney 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 Trabing Creek-North Piney Creek drainage divide area seen in less detail in figure 3. Little Goose Creek flows in a north and north-northeast direction along the west edge of figure 4. Trabing Creek originates in section 4 (south and west of center of figure 4) and flows in a north-northwest and north direction to the north edge of figure 4 and north of figure 4 joins north-northeast oriented Little Goose Creek. North Piney Creek flows in an east-northeast and east-southeast direction from the south edge of figure 4 (west half) to the east edge of figure 4 (near southeast corner). A southeast oriented North Piney Creek tributary originates in the southeast corner of section 4 and joins North Piney Creek in section 10. A through valley in section 4 links the north-northwest oriented Trabing Creek valley with the southeast oriented North Piney Creek tributary valley. The map contour interval for figure 4 is 40 feet and the through valley floor elevation is 6332 feet. The ridge to the east in section 3 rises to more than 6840 feet and elevations greater than 7000 feet can be found in the southwest corner of section 4. These elevations suggest the through valley is at least 500 feet deep. Another a slightly deeper through valley is located is located in section 3 and links a north-northwest oriented Trabing Creek tributary valley with a southeast and south oriented North Piney Creek tributary valley.  This section 3 through valley has an elevation of 6300 feet. Moncreiffe Ridge to the east rises to 6521 feet suggesting the through valley is at least 220 feet deep. The northwest to southeast oriented ridge between the two through valleys is streamlined and can best described as a streamlined erosional residual. The through valleys were eroded by diverging and converging southeast oriented flood flow channels and the erosional residual between them was streamlined by the southeast oriented flood flow. At the time floodwaters flowed in the flood flow channels there was no deep Little Goose Creek valley to the north. The south and southeast oriented flood flow was beheaded by headward erosion of the much deeper Tongue River valley (from the deep northeast oriented Yellowstone River valley, which eroded headward from space in the deep “hole the melting ice sheet had occupied). Floodwaters on the north end of the beheaded flood flow channels reversed flow direction to create the north oriented Little Goose Creek drainage route. The deep Tongue River knick point then eroded headward along the newly formed Little Goose Creek drainage route and captured significant flood flow from west of the actively eroding Tongue River valley head. Large volumes of such captured flood flow then moved along the newly reversed Little Goose Creek drainage route and eroded the deep north oriented Little Goose Creek valley.

East Fork Little Goose Creek-North Piney Creek drainage divide area

Figure 5: East Fork Little Goose Creek-North Piney Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 5 illustrates the East Fork Little Goose Creek-North Piney Creek drainage divide area south and west of figure 3 and there is a significant overlap area with figure 3. South Piney Creek flows in a north-northeast direction from the south edge of figure 5 (west of center) to the east edge of figure 5 (just north of the county line). North Piney Creek flows in a northeast and northeast direction from the south edge of figure 5 (west of South Piney Creek) and north of the county line turns to flow in an east direction to the east edge of figure 5. Stockwell Creek is an east oriented North Piney Creek tributary located near the center of figure 5. East of figure 5 North Piney Creek joins South Piney Creek to form southeast oriented Piney Creek. The East Fork Little Goose Creek originates just north of the south edge of figure 5 (west half) and flows in a north-northeast and north direction to north of the county line where it is joined by northeast, north, and north-northeast West Fork Little Goose Creek to form Little Goose Creek. Once formed Little Goose Creek flows in a north-northeast, southeast, and north direction to the north center edge of figure 5. A through valley links the north-northeast oriented East Fork Little Goose Creek valley with the east oriented Stockwell Creek valley. The map contour interval for figure 5 is 20 meters and the through valley floor elevation is between 2600 and 2620 meters. Little Goose Peak to the north of the through valley rises to 2852 meters and much higher elevations are found south of the through valley. These elevations suggest the through valley is at least 230 meters deep. The through valley was eroded by south oriented flood flow on the present day north oriented East Fork Little Goose Creek alignment flowing in an east direction to what was at that time the actively eroding Stockwell Creek valley. Flood flow in the through valley ended when headward erosion of the much deeper Tongue River valley beheaded south oriented flood flow on the present day north oriented Little Goose Creek alignment and the deeper valley knick point then eroded headward to beheaded south oriented flood flow on the East Fork Little Goose Creek alignment. The beheaded flood flow then reversed direction to create the north oriented East Fork Little Goose Creek drainage route and the deeper knick point then eroded headward along that route and beheaded the flood flow channel to the east oriented Stockwell Creek valley.

Detailed map of East Fork Little Goose Creek-Stockwell Creek drainage divide area

Figure 6: Detailed map of East Fork Little Goose Creek-Stockwell Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 6 provides a detailed topographic map of the East Fork Little Goose Creek-Stockwell Creek drainage divide area seen in less detail in figure 5. The East Fork Little Goose Creek flows in a north direction from the south edge of figure 6 (near southwest corner) to the north edge of figure 6 (west half). North of figure 6 Little Goose Creek joins Big Goose Creek to form north oriented Goose Creek, which then joins the northeast oriented Tongue River (which flows to the northeast oriented Yellowstone River). Stockwell Creek originates in section 28 and flows in an east direction to the east edge of figure 6 (north of center) and east of figure 6 joins north-northeast oriented North Piney Creek. East and north of figure 6 North Piney Creek turns to flow in an east direction and joins South Piney Creek to form southeast oriented Piney Creek, which eventually joins northeast oriented Clear Creek, which then joins the north and northeast oriented Powder River (which also joins the northeast oriented Yellowstone River). A through valley in the north half of section 28 links the east oriented Stockwell Creek valley with the north oriented East Fork Little Goose Creek valley. The map contour interval for figure 6 is 40 feet and the through valley floor elevation is between 8520 and 8560 feet. Little Goose Peak is just north of figure 6 and reaches an elevation of 9358 feet. Elevations greater than 9400 feet can be seen is section 33 near the south edge of figure 6. These elevations suggest the through valley is at least 800 feet deep. The through valley is a water-eroded feature and was eroded by east oriented flood flow moving to what at that time was the actively eroding Stockwell Creek valley. At that time floodwaters were moving in a south direction on the East Fork Little Goose Creek alignment. Flood flow on the East Fork Little Goose Creek alignment was beheaded and reversed to erode a much deeper north oriented valley on the East Fork Little Goose Creek alignment. The deeper north oriented valley ended all flood flow to the east oriented Stockwell Creek valley. It is possible and even probable that crustal warping was raising the Bighorn Mountains as these flood flow reversals took place and the crustal warping was a contributing factor in the flood flow reversal process.

East Fork Little Goose Creek-Kearney Creek drainage divide area

Figure 7: East Fork Little Goose Creek-Kearney Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 7 illustrates the East Fork Little Goose Creek-Kearney Creek drainage divide area south and west of figure 5 and includes an overlap area with figure 5. The dashed county line extending from near the northwest corner of figure 7 to the south center edge of figure 7 follows the Powder River-Bighorn Basin drainage divide with drainage west of the line to the Bighorn Basin. Emerald Lake is located just south of the county names in the west center area of figure 7. Shell Creek is the northwest oriented stream flowing from Emerald Lake to Shell Lake and then to the west edge of figure 7. North of Emerald Lake is Edelman Pass and then the headwaters of north-northeast oriented Edelman Creek, which flows to north and north-northeast oriented East Fork Big Goose Creek. East Fork Big Goose Creek originates north of Geneva Pass and flows in a north and north-northeast direction to the north edge of figure 7. Headwaters of south and southwest oriented Paint Rock Creek are located south of Geneva Pass. East of East Fork Big Goose Creek is north oriented Cross Creek, which originates at Cross Creek Lakes and flows in a north direction to join East Fork Big Goose Creek north of figure 7.  East of Cross Creek is the north-northeast oriented East Fork Little Goose Creek, which originates north of Highland Park and which flows to the north edge of figure 7 (east half). East of Highland Park, in the east center area of figure 7, are northeast oriented headwaters of North Piney Creek, which flows to the east edge of figure 7 (north half). South of Highland Park are headwaters of northeast oriented Kearney Creek, which flows to the east center edge of figure 7. East of figure 7 Kearney Creek joins north-northeast oriented South Piney Creek, which flows across the southeast corner of figure 7. Note north to south oriented through valleys or passes located directly south of the major north oriented valleys. The map contour interval for figure 7 is 20 meters. The Edelman Pass floor elevation is between 3120 and 3140 meters and elevations on either side exceed 3340 meters suggesting the pass is at least 200 meters deep. The Geneva Pass floor elevation is between 3140 and 3160 meters and elevations on either side rise to almost 3500 meters suggesting the pass is almost 340 meters deep. The pass or through valley south of Cross Creek Lakes has a floor elevation of between 3340 and 3360 meters and elevations on either side rise to more than 3460 meters suggesting the pass is at least 100 meters deep. The pass or through valley north of Highland Park has a floor elevation of between 3140 and 3160 meters and elevations on either side rise to more than 3300 meters suggesting the pass is at least 140 meters deep. Today these passes cross some of the highest regions in the Bighorn Mountains, yet these four passes provide evidence of four parallel south oriented flood flow channels that once crossed the region. These flood flow channels diverged from each other north of figure 7 and at least some of them converged south of figure 7. At the time floodwaters crossed the region the Bighorn Mountains did not stand high above surrounding regions as they do today. Floodwaters were flowing on a surface north of figure 7 that was at least as high as the pass floor elevations, if not higher. Deep erosion of regions north of figure 7 (including the western Powder River Basin) and uplift of the Bighorn Mountains as floodwaters flowed across them resulted in reversals of flood flow north of the passes to create the present day north oriented drainage routes.

Detailed map of East Fork Little Goose Creek-Kearney Creek drainage divide area

Figure 8: Detailed map of East Fork Little Goose Creek-Kearney Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 8 provides a detailed topographic map of the East Fork Little Goose Creek-Kearney Creek drainage divide seen in less detail in figure 7 above. The dashed line separating ranger districts near the southwest corner of figure 8 is also the drainage divide between the Powder River Basin to the north and east and the Bighorn Basin to the south and west. Cross Creek originates at the Cross Creek Lakes in section 28 and 21 and flows in a north direction to the north edge of figure 8 (west half) and north of figure 1 joins the north oriented East Fork Big Goose Creek. The East Fork Little Goose Creek flows from section 13 (north of Highland Park) in a north-northeast and north direction to the north edge of figure 8 (east half). Kearney Creek flows in a northeast direction from the south edge of figure 8 (east of center) to Kearney Lake reservoir and then in an east direction to the east edge of figure 8 (south half). A north to south oriented through valley or pass in the south half of section 28 (south of Cross Creek Lakes) links the north oriented Cross Creek valley with drainage routes to the Bighorn Basin. The map contour interval for figure 8 is 40 feet and the through valley floor elevation is between 10,960 and 11,000 feet. Elevations in section 27 rise to 11,760 feet and elevations in section 28 just west of the through valley rise to 11,480 feet. These elevations suggest the through valley is at least 480 feet deep. Another through valley in the southeast quadrant of section 22 links the north oriented Cross Creek valley with a southeast oriented Kearney Creek tributary valley. The floor elevation of this second through valley is between 10,880 and 10,920 feet. Elevations north and east of this second through valley rise to 11,370 feet suggesting the through valley is at least 450 feet deep. A third through valley or pass can be found north of Highland Park near the north border of section 24. This third through valley links the north-northeast oriented East Fork Little Goose Creek valley with the Kearney Creek valley. The floor elevation of this third through valley is between 10,320 and 10,360 feet. Elevations in section 18 to the east rise to 10,854 feet suggesting this third through valley is approximately 500 feet deep. The north oriented Cross Creek Lakes basin and the east oriented Lake Silver basin (in section 27) appear to be glacially carved cirques providing evidence of alpine glaciation in the region. While the alpine glaciers did modify some of the valley shapes the valleys existed before the glaciers. The valleys were eroded by flood flow that first moved across what were then the emerging Bighorn Mountains in a south direction from the present day Powder River Basin to the present day Bighorn Basin. Deep erosion of the Powder River Basin combined with Bighorn Mountains uplift (and/or emergence) beheaded and reversed the south oriented flood flow with headward erosion of the northeast oriented Kearney Creek valley being a step in the flood flow reversal process. The alpine glaciation occurred after the Bighorn Mountains had emerged as a high mountain range, which was after flood flow across the region had ended.

North Piney Creek-South Piney Creek drainage divide area

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

Figure 9 illustrates the North Piney Creek-South Piney Creek drainage divide area north and east of figure 7 and includes an overlap area with figure 7. Kearney Creek flows in a northeast direction from the southwest corner of figure 9 to Kearney Lake Reservoir and then to join north-northeast oriented South Piney Creek (north of Willow Park Reservoir). South Piney Creek flows in a north-northeast direction from the south edge of figure 9 (west half) to Willow Park Reservoir and then into the northeast quadrant of figure 9 where it turns to flow in a northeast direction to join North Piney Creek in the northeast corner of figure 9 (east of Story) and then to flow in a southeast direction as Piney Creek to the east edge of figure 9 (near northeast corner). North Piney Creek originates in the southwest quadrant of figure 9 and flows in a north-northeast direction through Penrose Park to the north edge of figure 9 (east of center) and north of figure 9 turns to flow in an east and east-southeast direction and joins South Piney Creek east of Story in the northeast corner of figure 9 to form southeast oriented Piney Creek. The East Fork Little Goose Creek originates near the west edge of figure 9 (north of Highland Park) and flows in a north-northeast direction to the north edge of figure 9 (west half). Note how the North Piney Creek headwaters in the southwest quadrant of figure 9 originate along the Kearney Creek north valley wall and then flow into a separate valley to the Penrose Park area where North Piney Creek is flowing in a relatively shallow valley carved into a sloping surface that leads down to the much deeper South Piney Creek valley. The Kearney Creek valley is deeper than the North Piney Creek valley to the north and drains to the deeper South Piney Creek valley. These roughly parallel valleys at different elevations suggest the Kearney Creek-South Piney Creek valley was eroded deeper than the North Piney Creek valley, which means the Kearney Creek and South Piney Creek valleys received significantly more flood flow than the North Piney Creek valley. At first glance the suggestion might be made that the additional flood flow came from the alpine glaciers in the Kearney Creek and South Piney Creek headwaters area. But would melt water from relatively small alpine glaciers be able to erode the much deeper valleys seen in figure 9? Another and perhaps better explanation is south oriented flood flow on the South Piney Creek alignment was beheaded and reversed by headward erosion of the southeast oriented Piney Creek valley before headward erosion of the Tongue River valley beheaded and reversed flood flow on the north oriented East Fork Little Goose Creek alignment was beheaded and reversed. The northeast oriented Kearney Creek valley then eroded headward from the reversed flood flow on the South Piney Creek alignment to capture south oriented flood flow on the East Fork Little Goose Creek alignment. This captured flood flow enabled Kearney Creek and South Piney Creek to erode much deeper valleys than the reversed flood flow on the North Piney Creek alignment was able to erode without the benefit of the large volumes of captured flood flow.

Detailed map of North Piney Creek-South Piney Creek drainage divide area

Figure 10: detailed map of North Piney Creek-South Piney Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 10 provides a detailed topographic map of the North Piney Creek-South Piney Creek drainage divide area seen in less detail in figure 9. South Piney Creek flows in a north direction from the south edge of figure 10 (slightly east of center) across section 13 and then turns to flow in a north-northeast and northeast direction to the northeast corner of figure 10. North Piney Creek flows in a northeast, north-northeast, and north direction from the south edge of figure 10 (west half) to the north edge of figure 10 (east half). Penrose Park is located along the North Piney Creek-South Piney Creek drainage divide in sections 11, 2, 1, 31, and 36. The map contour interval for figure 10 is 40 feet. At the south end of Penrose Park North Piney Creek flows across the northwest corner of section 11 and crosses the 8200-foot contour line. A north-northeast oriented South Piney Creek tributary originates in a swamp near the southeast corner of section 11 along the 8200-foot contour line and then flows parallel to the adjacent North Piney Creek and South Piney Creek valleys before finally joining South Piney Creek near the border between sections 31 and 32. These parallel valleys suggest the possibly of diverging and converging north-northeast oriented flood flow channels. If correctly interpreted the floodwaters were captured south and west of figure 10 from south oriented flood flow moving on the present day north oriented East Fork Little Goose Creek alignment and then flowed in a north-northeast direction across the region seen in figure 10. Through valleys used by the floodwaters to reach the North and South Piney Creek valley were shown in figures 7 and 8. Apparently some of the captured flood flow reached the North Piney Creek valley and also the valley of the north-northeast oriented South Piney Creek valley as well as the deeper Kearney Creek and South Piney Creek valleys. If correctly interpreted the slopes seen in figure 10 were eroded by this reversed flood flow moving to the much deeper southeast oriented Piney Creek valley north and east of figure 10.

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.