Madison River-Gallatin River drainage divide area landform origins in northwest Yellowstone National Park region, Montana and Wyoming, USA

Authors


Abstract:

This essay uses topographic map evidence to interpret landform origins between the Madison River and Gallatin River in the northwest Yellowstone National Park region, Montana and Wyoming. The northwest Yellowstone National Park region as defined here includes the Yellowstone National Park northwest corner and the region west to the north-northwest oriented Madison River valley. The Madison River flows in a northwest, southwest, and north-northwest direction from Yellowstone National Park along the study region’s south and west margins while the Gallatin River flows in a northwest direction across the study region’s northeast boundary. Taylor Creek is a southeast, northeast, and east oriented Gallatin River tributary located along the study region’s north border. North-to-south and northwest-to-southeast oriented through valleys or passes cross the Gallatin River-Madison River drainage divide and also cross present day northeast oriented Gallatin River tributary drainage divides and drainage divides between west oriented and southwest oriented Madison River tributaries. These through valleys or passes were eroded by south and southeast oriented flood flow channels that flowed on a surface now preserved, if preserved at all, by the highest study region mountain ridges. Barbed tributaries and drainage route U-turns provide additional evidence of these former flood flow channels. Flood flow channels were first captured and diverted in different directions by headward erosion of deeper and deeper south oriented flood flow channels, which eroded headward along the present day north oriented Madison and Gallatin River alignments and which contributed to the region mountain range emergence. Floodwaters were derived from the western margin of a melting thick North American ice sheet and were flowing from western Canada across Montana to and across the study region. The ice sheet presence caused crustal warping that raised regional mountain ranges and the Yellowstone Plateau and that further contributed to the emergence of regional mountain ranges. Headward erosion of a deep northeast oriented valley from space in the deep “hole” the melting ice sheet was opening up captured the south and southeast oriented floodwaters and beheaded the south oriented flood flow channels on the Gallatin and Madison River alignments. Floodwaters on north ends of the beheaded flood flow channels, aided by the region uplift, reversed flow direction to create the north oriented Gallatin and Madison River drainage systems seen today.

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 Madison River-Gallatin River drainage divide area landform origins in the northwest Yellowstone National Park region, Montana and Wyoming and 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 Madison River-Gallatin River drainage divide area landform evidence in the northwest Yellowstone National Park region, Montana and Wyoming will be regarded as evidence supporting the “thick ice sheet that melted fast” paradigm.

Madison River-Gallatin River drainage divide area location map

Figure 1: Madison River-Gallatin River 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 Madison River-Gallatin River drainage divide in the northwest Yellowstone National Park region, Montana and Wyoming and illustrates in the north a region in southwest south central Montana with the northwest corner of Wyoming and the northern region of Yellowstone National Park appearing in the southeast quadrant of figure 1 and a northeast Idaho region located in the southwest quadrant of figure 1 west of Yellowstone National Park. The Madison River originates in Yellowstone National Park south of Mount Holmes (in Yellowstone National Park western region) and flows in a northwest direction to Hegben Lake (just west of Yellowstone National Park) and then flows in a west and southwest to direction through Earthquake Lake before turning to flow in a north direction west of the Madison Range to Three Forks, Montana. At Three Forks the north oriented Madison River joins the north and northwest oriented Gallatin River and the northeast and east oriented Jefferson River to form the north oriented Missouri River, which flows to the north center edge of figure 1. North of figure 1 the Missouri River turns to flow in a northeast and then east direction to North Dakota where it turns again to flow in a southeast and south direction with water eventually reaching the Gulf of Mexico. The Gallatin River originates in the northwest corner of Yellowstone National Park and flows in a northwest and north direction near Big Sky, Gallatin Gateway and Manhattan before turning to flow again in a northwest direction to join the Madison and Jefferson Rivers at Three Forks. This essay investigates Madison River-Gallatin River drainage divide area in the Yellowstone National Park northwest corner region and directly to the west including areas north of Hebgen and Earthquake Lakes. Separate essays address landform origins in the middle Madison Range area (south of Ennis Lake and Big Sky and includes Big Sky) and the northern Madison Range area (north of Ennis Lake and Big Sky).

A brief look at the big picture erosion history will help understand discussions related to detailed maps shown below. Large volumes of south and southeast oriented floodwaters once flowed across the region shown by figure 1. Floodwaters were derived from the western margin of a melting thick North American ice sheet and were flowing in a south and southeast direction from western Canada to and across the figure 1 region. North oriented rivers in figure 1, including the north oriented Madison, Gallatin, and Missouri Rivers, are generally flowing in valleys that originated as south oriented flood flow channels. When floodwaters first flowed across the region the mountain ranges, deep river valleys, and the basins between the mountain ranges did not exist and floodwaters could freely flow across the region. Mountain ranges emerged as floodwaters flowed across the region and initially floodwaters flowed across what are today high mountain ranges including the Madison RAnge (between the north oriented Madison and Gallatin Rivers). The Madison and Gallatin Rivers originated as a south oriented flood flow channels, which were subsequently reversed to form the north oriented drainage routes seen today. The flood flow reversal was probably indirectly caused by crustal warping that occurred as melt water floods flowed across the region with the crustal warping being related to a thick ice sheet presence north and east of figure 1, although the direct cause was headward erosion of a deep northeast oriented valley across Montana (north of figure 1), which beheaded the south oriented flood flow channels supplying floodwaters to the south oriented Madison and Gallatin River flood flow channels. The deep northeast oriented valley was eroding headward from space in the deep “hole” the melting ice sheet had occupied and was capturing the south and southeast oriented ice-marginal melt water floods and diverting the floodwaters into the deep “hole” the ice sheet had formed. This northeast oriented valley was much deeper than the beheaded flood flow channels and floodwaters on north ends of the beheaded flood flow channels reversed flow direction to create the north oriented Missouri River segment and the north oriented Madison and Gallatin River drainage routes seen in figure 1.

Detailed location map for Madison River-Gallatin River drainage divide area

Figure 2: Detailed location map Madison River-Gallatin River 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 Madison River-Gallatin River drainage divide area in the southern Madison Range located in the northwest Yellowstone National Park region, Montana and Wyoming and shows drainage routes not seen in figure 1. Green shaded areas are National Forest lands, which generally are located in mountainous regions. The Madison River is formed at the confluence of the south and west oriented Gibbon River and north oriented Firehole River at Madison Junction, Wyoming (in Yellowstone National Park near south edge of southeast quadrant of figure 2). From Madison Junction the Madison River flows in a west and northwest direction to Hebgen Lake and then in a southwest direction through Earthquake Lake to Cliff, Montana. From Cliff the Madison River flows in a north-northwest direction to the north edge of figure 2 (near northwest corner). Madison River tributaries of interest in this essay include northwest and south-southwest oriented Grayling Creek (which flows from near Mount Holmes in Yellowstone National Park to Hebgen Lake) and south-southeast oriented Tepee Creek (which joins Grayling Creek near the Park boundary) and other unnamed south oriented streams west of Yellowstone National Park. The Gallatin River originates in the northwest corner of Yellowstone National Park near Mount Holmes and flows in a northwest direction to the south-to-north oriented highway located near the center of figure 2. From the Yellowstone National Park northwest corner to the north center edge of figure 2 the highway is located in the Gallatin River valley. Gallatin River tributaries of interest in this essay include the unnamed east-northeast oriented stream (Bacon Rind Creek on more detailed maps) originating near Redstreak Mountain, north-northeast oriented Sage Creek, southeast, northeast, and east oriented Taylor Fork (Creek on more detailed maps. Detailed maps show many other Madison and Gallatin River tributaries in this essay’s study region,  which is defined here as the region between the Gallatin and Madison Rivers and south of Taylor Fork (Creek)

Gallatin River-Grayling Creek drainage divide area

Figure 3: Gallatin Rive-Grayling Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 3 provides a topographic map of the Gallatin River-Grayling Creek drainage divide area. The Gallatin River originates at Gallatin Lake (near east center edge of figure 3) and flows in a northwest, west-southwest, and northwest direction to the north edge of figure 3 (west of center). North of figure 3 the Gallatin River turns to flow in more of a north direction. Grayling Creek originates in the southeast quadrant of figure 3 and flows in a north, northwest, and west direction to the north-south highway location and then continues in a south and southwest direction to enter Hebgen Lake and join the northwest oriented Madison River in the southwest corner of figure 3 (the highway is located in the Grayling Creek valley). The south oriented stream joining Grayling Creek where it turns from flowing in a west direction to flowing in a south direction is Pass Creek. The south and southwest oriented stream in the southeast corner of figure 3 is Maple Creek, which south of figure 3 flows in a southwest direction to join northwest oriented Cougar Creek, which then joins west oriented Duck Creek to flow into Hebgen Lake and join the Madison River. Note how a northwest-to-southeast oriented through valley links the north oriented Grayling Creek headwaters valley with the south oriented Maple Creek valley. The map contour interval for figure 3 is 50 meters and the through valley floor elevation at the drainage divide is between 2500 and 2550 meters. The Crags to the west rise to 2845 meters while Three Rivers Peak to the east rises to 3035 meters suggesting the through valley may be as much as 300 meters deep. This through valley is a water-eroded feature and was eroded by southeast oriented flood flow. Another much more intriguing north-to-south oriented through valley is used by the north-to-south oriented highway and links the south oriented Pass Creek-Grayling Creek valley with the northwest and north oriented Gallatin River valley. The through valley floor elevation where the road crosses the drainage divide is between 2200 and 2250 meters. Using elevations near the road the through valley appears to be only 100-150 meters deep. But, west of figure 3 elevations rise to more than 3000 meters and elevations greater than 3000 meters can be found along the east edge of figure 3 suggesting the through valley may be as much 800 meters deep. The narrower inner through valley is definitely a water-eroded feature and was eroded by south oriented flood flow prior to the reversal of flood flow in the Gallatin River valley. The broader and deeper through valley is at least in part a water-eroded feature, although it possible crustal warping also played a role in its formation. The broader and deeper through valley was eroded by massive south oriented flood flow that once crossed the region. At that time the Yellowstone Plateau region did not stand high above regions to the north and south and southeast oriented melt water floods could flow easily into and across the region.

Detailed map of Gallatin River-Pass Creek drainage divide area

Figure 4: Detailed map of Gallatin River-Pass 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 Gallatin River-Pass Creek drainage divide area seen in less detail in figure 3. The Gallatin River (unlabeled in figure 4) flows in a west and northwest direction in the northeast quadrant of figure 4 and north of figure 4 turns to flow in more of a north direction. Grayling Creek flows in a west and then south direction in the southeast quadrant of figure 4 and south of figure 4 flows in a south and southwest direction to enter Hebgen Lake and to join the north oriented Madison River. Pass Creek is the south oriented stream joining Grayling Creek at the point where Grayling Creek turns to flow in a south direction. Divide Lake is located near the highway and is north of the Pass Creek headwaters. The highway between Divide Lake and the south oriented Pass Creek valley is located in a north-to-south oriented through valley linking the northwest and north oriented Gallatin River valley with the south oriented Grayling Creek valley. The map contour interval for figure 4 is 40 feet and the through valley floor elevation at the drainage divide is between 7240 and 7280 feet. Elevations west of the through valley and seen in figure 4 rise to more than 8000 feet while elevations on the Gallatin River-Grayling Creek drainage divide east of the through valley (and seen in figure 4) rise to more than 7800 feet. These elevations suggest the through valley is at least 500 feet deep. Much higher elevations can be found both east and west of figure 4 suggesting there may be a much broader and deeper north-to-south oriented through valley and that the Divide Lake-Pass Creek through valley seen in figure 4 is simply a deep channel eroded into the floor of that much broader and deeper through valley. The through valley (or valleys) was (were) eroded by south oriented flood flow moving from the present day northwest and north oriented Gallatin River alignment to the south oriented Grayling Creek alignment. A reversal of flood flow on the Gallatin River alignment ended south oriented flood flow across the divide.

Sage Creek-Bacon Rind Creek drainage divide area

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

Figure 5 illustrates the Sage Creek-Bacon Rind Creek drainage divide area north and west of figure 3 and includes a small overlap area with figure 3. Divide Lake can be seen near the highway in the southeast corner region of figure 5. North of Divide Lake the highway follows the north and northwest oriented Gallatin River valley to the north edge of figure 5 (east of center). Note southwest oriented streams joining the north oriented Gallatin River as barbed tributaries in the northeast quadrant of figure 5. These barbed tributaries provide additional evidence of former south oriented diverging and converging flood flow channels. Northeast and north-northeast streams flowing from the south end of the Madison Range to the north oriented Gallatin River include Bacon Rind Creek, Snowslide Creek, Monument Creek. Sage Creek is a north-northeast stream west of Monument Creek and north of figure 5 Sage Creek flows to the northwest oriented Gallatin River. The south and southwest oriented stream flowing to the southwest corner of figure 5 is Cub Creek, which south and west of figure 5 flows to the Madison River. The Sage Creek-Cub Creek drainage divide seen in figure 5 is located on the east side of a broad north-to-south oriented through valley seen in figure 7, which provides evidence of south oriented flood flow across what are today the high Madison Range mountains. A more subtle through valley can be seen in figure 5 and extends from the Sage Creek valley near the north edge of figure 5 in a south-southeast direction just west of Monument Meadow and then across the Monument Creek-Snowslide Creek drainage divide and continues across the Snowslide Creek-Bacon Rind Creek drainage divide. The through valley can be best be seen crossing the present day Monument Creek-Snowslide Creek and Snowslide Creek-Bacon Rind Creek drainage divides. The map contour interval for figure 5 is 50 meters and the through valley is defined by three contour lines on the east side on the Monument Creek-Snowslide Creek drainage divide and by two contour lines on the east side on the Snowslide Creek-Bacon Rind Creek drainage divide. This through valley was eroded by south-southeast oriented flood flow prior to headward erosion of the northeast oriented Bacon Rind Creek valley, which captured the south-southeast oriented flood flow and diverted floodwaters to what was probably a newly reversed north oriented flood flow channel on the Gallatin River alignment. Next headward erosion of the northeast oriented Snowslide Creek valley captured the south-southeast oriented flood flow and finally headward erosion of the north-northeast oriented Monument Creek captured the flood flow. Sage Creek valley headward erosion occurred along what was the north end of a beheaded south oriented flood flow channel better seen in figure 7.

Detailed map of Monument Creek-Snowslide Creek drainage divide area

Figure 6: Detailed map of Monument Creek-Snowslide 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 Monument Creek-Snowslide Creek drainage divide area seen in less detail in figure 5. The highway near the east edge of figure 6 is located in the north and northwest oriented Gallatin River valley. Snowslide Creek flows in a northeast direction from the south center edge of figure 6 to join the north oriented Gallatin River. Monument Mountain is located in section 12 in the southwest quadrant of figure 6. Monument Creek originates on the north side of Monument Mountain and flows in a north-northeast direction to join the northwest Gallatin River just north of the north edge of figure 6. Big Spring Creek is a north oriented Gallatin River tributary flowing to the north edge of figure 6 near the northwest corner. Monument Meadow is a labeled location in section 31. West of Monument Meadow a northwest-to-southeast oriented through valley or pass links a north-northwest and west-northwest oriented Big Spring Creek tributary valley with a south-southeast oriented Monument Creek tributary valley. The map contour interval for figure 6 is 40 feet and the through valley floor elevation at the drainage divide is between 8960 and 9000 feet. To the east in section 31 elevations rise to more than 9280 feet while to the southwest in section 1 elevations rise to 9371 feet suggesting the through valley is 280 feet deep. The through valley can be traced in a southeast direction across the Monument Creek-Snowslide Creek drainage divide. In the east half of section 5 the through valley elevation at the drainage divide is between 8640 and 8680 feet. In section 4 to the east elevations rise to 9076 feet while elevations to the west rise much higher suggesting this southeast extension of the through valley is at least 396 feet deep. As seen in figure 5 the through valley can be traced further to the south and east across the Snowslide Creek-Bacon Rind Creek drainage divide. This through valley was eroded by a south-southeast oriented flood flow channel prior to headward erosion of the much deeper northeast oriented Snowslide Creek and the north-northeast oriented Monument Creek valleys. At the time the flood flow channel was eroded it was probably one several diverging and converging flood flow channels crossing the region. The present day north oriented Gallatin River valley is located on the alignment of another of the diverging and converging south oriented flood flow channels and when beheaded and reversed to flow in a north direction was able to capture the south-southeast flood flow from the adjacent and yet to be beheaded and reversed flood flow channel by headward erosion of deep northeast oriented tributary valleys.

Taylor Creek-Beaver Creek drainage divide area

Figure 7: Taylor Creek-Beaver Creek drainage divide. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 7 illustrates the Taylor Creek-Beaver Creek drainage divide area west and slightly south of figure 5 and includes a significant overlap area with figure 5. The Madison-Gallatin County line is marked and labeled. Beaver Creek is the south oriented stream flowing to the south edge of figure 7 near the county line. South of figure 7 Beaver Creek flows to the west and north oriented Madison River. North of the south oriented Beaver Creek headwaters is Lightning Lake (near Apex Point) and Lightning Creek flows in a north direction from Lightning Lake to join northeast oriented Taylor Creek, which then flows to the north edge of figure 7 (west of center). North of figure 7 Taylor Creek turns to flow in an east direction along the north edge of figure 7 to join the north oriented Gallatin River just north of the northeast corner of figure 7. The Sage Basin is located in the south center area of figure 7 (east of Beaver Creek) and is where Sage Creek originates. From the Sage Basin Sage Creek flows in a northeast and north-northeast direction to near the northeast corner of figure 7 and then to join the northwest oriented Gallatin River. Note how there is a broad north-to-south oriented through valley linking the north-oriented Gallatin River tributary valleys with the south oriented Beaver Creek valley. The map contour interval for figure 7 is 50 meters and the Lightning Creek-Beaver Creek drainage divide appears to be between 2600 and 2650 meters (near the county line). To the west elevations rise to 3247 meters at Sage Peak in the southeast quadrant of figure 7 while to the west elevations greater than 3250 meters can be found near several of the higher peaks. These elevations suggest the broad north-to-south oriented through valley is approximately 600 meters deep. This broad through valley was eroded by south oriented flood flow prior to a reversal of flood flow caused by headward erosion of the deep east and northeast oriented Taylor Creek valley. Note in the northwest quadrant of figure 7 southeast oriented Taylor Creek headwaters and east and southeast oriented Tumbledown Creek, which provide evidence headward erosion of the deep northeast oriented Taylor Creek valley captured southeast oriented flood flow channels, which must have been moving floodwaters across a surface equivalent in elevation to the high peaks seen in the Taylor Peaks region. At that time the Madison Range did not stand high above the surrounding region and floodwaters from the north and northwest could freely flow across the region.

Detailed map of Lightning Creek-Beaver Creek drainage divide area

Figure 8: Detailed map of Lightning Creek-Beaver 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 Lightning Creek-Beaver Creek drainage divide area seen in less detail in figure 7. Taylor Creek flows in a northeast direction across the northwest corner of figure 8. North and east of figure 8 Taylor Creek flows to the north oriented Gallatin River. Lightning Creek originates at Lightning Lake in the northwest corner of section 9 and flows in a north-northwest direction to join northeast oriented Taylor Creek just north of the north edge of figure 8. Beaver Creek originates in section 9 just south of Lightning Lake and flows in a south-southeast direction to the south edge of figure 8 (west of center). South of figure 8 Beaver Creek flows to the west and north oriented Madison River. A well-defined north-to-south oriented through valley in section 9 links the north oriented Lightning Creek valley with the south oriented Beaver Creek valley. The map contour interval for figure 8 is 40 feet and the through valley floor elevation at the drainage divide is 8361 feet. Apex Point in the southeast corner of section 4 to the east rises to 9367 feet and Moose Mountain to the west rises to 9403 feet suggesting the through valley is at least 1000 feet deep. But as seen in figure 7 much higher elevations exist both to the east and to the west of figure 8. Pyramid Peak west of figure 8 rises to 10,541 feet while Sage Peak to the east rises 10,563 feet. Based on these more distance elevations the 1000-foot deep north-to-south oriented through valley seen in figure 8 may be just a deep channel eroded into the floor of what was once a much broader and deeper north-to-south oriented through valley. The much broader through valley may have been as much as 2200 feet deep and would have been eroded into a surface equivalent in elevation to the tops of the high mountains in the surrounding region. The through valleys were eroded by south oriented south oriented flood flow channels prior to the emergence of the Madison Range as a high mountain range. South oriented flood flow to the Beaver Creek valley was beheaded by headward erosion of the much deeper northeast oriented Taylor Creek valley. Floodwaters on the north end of the beheaded flood flow channel reversed flow direction to create the north oriented Lightning Creek drainage route.

Papoose Creek-Madison River drainage divide area

Figure 9: Papoose Cree-Madison River drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 9 illustrates the Papoose Creek-Madison River drainage divide area south and west of figure 7 and includes an overlap area with either figure 3 or 5. Hebgen Lake straddles the east edge of figure 9 (near southeast corner) and floods the northwest oriented Madison River valley. At Hebgen Dam the Madison River turns to flow in a southwest direction through Earthquake Lake before turning to flow in a northwest and north-northwest direction to the northwest corner of figure 9. Beaver Creek is the south oriented stream flowing from the north edge of figure 9 to join the Madison River at Earthquake Lake. Papoose Creek originates in the Cradle Lakes region (slightly south of center of figure 9) and flows in a northwest, west, and southwest direction to join the Madison River near the west center area of figure 9. Note how other Madison River tributaries also flow in southwest directions to join the northwest and north oriented Madison River as barbed tributaries. The Cradle Lake area is located in a high mountain region, which shows evidence of having been glaciated with alpine glaciers that once filled higher-level valleys. The glaciation occurred after valleys were formed and this essay is concerned with the original valley formation so the glaciation is noted, but not otherwise discussed. South and east of Cradle Lakes is Rock Creek, which is a south-southeast oriented stream flowing to the southwest oriented Madison River at Earthquake Lake. While somewhat difficult to see in figure 9 the northwest oriented Papoose Creek valley in the Cradle Lakes area is linked by a through valley with the south-southeast oriented Rock Creek valley. The map contour interval for figure 9 is 50 meters and the through valley floor elevation at the drainage divide is between 3000 and 3050 meters. Elevations on either side of the through valley rise to more than 3100 meters suggesting the through valley is at least 50 meters deep. A deeper through valley links the northwest oriented Papoose Creek headwaters valley with the southwest and west oriented Deadman Creek valley, which drains to the northwest oriented Madison River valley. The floor of this deeper through valley at the drainage divide is between 2950 and 3000 meters suggesting the through valley is more than 100 meters deep. While difficult to imagine based on today’s topography these through valleys record the history of a southeast oriented flood flow channel. The southeast oriented flood flow channel at one time continued from the present day northwest oriented Papoose Creek headwaters alignment to the southeast oriented Rock Creek alignment and may have converged with a south and southwest oriented flood flow channel on the Beaver Creek and southwest oriented Madison River alignment. Near the south center of figure 9 that southwest oriented flood flow channel converged with a south-southeast oriented flood flow channel on the present day north-northwest oriented Madison River alignment. The southwest and west oriented Deadman Creek valley eroded headward from the south-southeast oriented flood flow channel to capture the southeast oriented flood flow channel in the Cradle Lakes region. Next headward erosion of a much deeper south-southeast oriented flood flow channel on the Madison River alignment enabled the southwest and west oriented Papoose Creek valley to erode headward and to capture the southeast oriented flood flow channel. Floodwaters on the northwest end of the beheaded flood flow channel reversed flow direction to create the northwest oriented Papoose Creek headwaters valley. The high mountains in figure 9 emerged as floodwaters eroded deeper and deeper flood flow channels into and around what was a rising mountain mass, which was rising because crustal warping related to the thick ice sheet presence north and east of the study region was raising the entire region.

Detailed map of Papoose Creek-Rock Creek drainage divide area

Figure 10: Detailed map of Papoose Creek-Rock 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 Papoose Creek-Rock Creek drainage divide area seen in less detail in figure 9. Earthquake Lake floods the southwest oriented Madison River valley in the southeast corner of figure 10. The northeast edge of the northwest oriented Madison River valley can be seen in the southwest corner of figure 10. Papoose Creek originates in section 10 (north and east of the center of figure 10) and flows in a northwest direction into section 4 and then flows in a west and west-southwest direction to the west edge of figure 10 (near northwest corner). Deadman Creek originates in the southwest corner of section 15 and flows in a southwest and west direction to the west edge of figure 10 (south half) and joins the northwest oriented Madison River west of figure 10. Rock Creek originates in section 14 and flows in a southeast and south-southeast direction to join the southwest oriented Madison River south of the figure 10 (east of center). The Papoose Creek-Deadman Creek through valley can be seen in the northeast corner of section 15 and the Papoose Creek-Rock Creek through valley can be seen near the west edge of section 14. Today these through valleys are nothing more than high mountain passes, but they are water-eroded features and were eroded at a time when southeast oriented floodwaters flowed across the region on a surface equivalent in elevation to the tops of high ridges seen in figure 10. Initially floodwaters flowed in a southeast direction from the present day northwest oriented Papoose Creek alignment to the southeast oriented Rock Creek alignment. Headward erosion of the deeper southwest oriented Deadman Creek valley then captured the southeast oriented flood flow and diverted the floodwaters in a southwest direction. Subsequently headward erosion of the still deeper southwest and west oriented Papoose Creek valley captured the southeast oriented flood flow and diverted the floodwaters in a west and southwest direction. Floodwaters on the northwest end of the beheaded flood flow channel then reversed flow direction to create the northwest oriented Papoose Creek drainage route. Headward erosion of deeper and deeper flood flow channels lowered surrounding base levels as crustal warping further contributed to the emergence of the high mountains. A reversal of flood flow direction in the adjacent Madison River valley subsequently created the north oriented Madison River drainage system. Finally after present day drainage patterns had been established and after the Madison Range had fully emerged as the high mountain range it is today alpine glaciers formed in some of the higher valleys including the Papoose Creek headwaters valley and further modified some of the high mountain regions.

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.

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