A geomorphic history based on topographic map evidence

Massive south and southeast oriented floods eroded the Turkey Creek-Little Blue River drainage divide area in Saline, Jefferson, and Gage Counties, Nebraska. Flood waters were probably derived from a rapidly melting thick North American ice sheet. Flood waters initially flowed on a topographic surface higher than the highest regional elevations today and were flowing to what was then a newly eroded east-oriented and deep Kansas River valley. The deep Big Blue River valley and its tributary valleys eroded headward from the what was then the actively eroding Kansas River valley. Headward erosion of Big Blue River tributary valleys progressed in sequence from south to north. Little Blue River valley headward erosion occurred first. The Horseshoe Creek valley then eroded headward and beheaded some flood flow routes to the newly eroded Little Blue River valley. Headward erosion of the Big Blue River valley next beheaded a southwest-oriented flood flow channel to the newly eroded Horseshoe Creek valley and the resulting flood flow reversal created the valley beheaded south-oriented flood flow routes to the newly created Big Indian Creek drainage system. Swan Creek valley headward erosion then beheaded south-oriented flood flow to the newly eroded Cub Creek valley and finally Turkey Creek valley headward erosion beheaded south-oriented flood flow to the newly eroded Swan Creek valley.

Preface:

• The purpose of this essay is to use topographic map interpretation methods to explore Turkey Creek-Little Blue River drainage divide area landform origins in Saline, Jefferson, and Gage Counties, Nebraska, 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 the 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 Turkey Creek-Little Blue River drainage divide area landform origins in Saline, Jefferson, and Gage Counties, Nebraska will be regarded as evidence supporting the “thick ice sheet that melted fast” paradigm. This essay is included in the Missouri River drainage basin landform origins research project essay collection.

Turkey Creek-Little Blue River drainage divide area location map

Figure 1: Turkey Creek-Little Blue 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 Turkey Creek-Little Blue River drainage divide area in Saline, Jefferson, and Gage Counties, Nebraska location map. The Missouri River is the southeast-oriented river in the figure 1 northeast quadrant. West of the Missouri River the state in the figure 1 north half is Nebraska while Kansas is in the figure 1 south half. The state of Missouri is east of the Missouri River, with Iowa north of Missouri in the figure 1 northeast corner. The Kansas River can be seen along the figure 1 south edge (east half) and flows through Manhattan, Wamego, St. Marys, Rossville, Silver Lake, and Perry and continues east of the figure 1 map area to join the Missouri River at Kansas City. From Kansas City the Missouri River flows in an east direction  join the south-oriented Mississippi River. The Big Blue River flows in a south-southeast direction from the figure 1 north center edge to Crete, De Witt, Beatrice, Blue Springs, and Wymore, Nebraska and into Kansas. In Kansas the Big Blue River flows to Marysville and Blue Rapids before joining the east-oriented Kansas River near Manhattan. The Little Blue River flows in a southeast direction from the figure 1 west edge (south of Hastings, Nebraska) to Hebron and Fairbury, Nebraska and then to Hanover and Waterville, Kansas before joining the Big Blue River near Blue Rapids. Turkey Creek is the unlabeled Big Blue River tributary flowing through Geneva, Nebraska and joining the Big Blue River near De Witt, Nebraska. Little Sandy Creek is the unlabeled southeast-oriented tributary joining the Little Blue River upstream from Fairbury, Nebraska. Big Sandy Creek is the unlabeled southeast-oriented tributary flowing from near Hastings to Carleton and Alexandria before joining the Little Blue River. The Platte River-Big Blue River drainage divide area, the Little Blue River-Republican River drainage divide area, and the Big Blue River-Big Nemaha River drainage divide area essays have addressed nearby drainage divide areas and can be found under Big Blue River and other appropriate river names on the sidebar category list.  Hundreds of published Missouri River drainage basin landform origins research project essays on this website collectively describe evidence for massive south-oriented melt water floods, which flowed across the states of Nebraska and Kansas. Flood waters were probably derived from a rapidly melting thick North American ice sheet. The east-oriented Kansas River valley eroded headward across Kansas to capture the south-oriented flood water and to divert the flood water to the Mississippi River valley. The Big Blue River valley eroded headward from the actively eroding Kansas River valley head. Big Blue River tributary valleys, including the Little Blue River valley and the Turkey Creek valley,  eroded headward from the actively eroding Big Blue River valley head. Big Blue River tributary valleys eroded headward in sequence from south to north.

Turkey Creek-Little Blue River drainage divide area detailed location map

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

Figure 2 provides a slightly more detailed location for the Turkey Creek-Little Blue River drainage divide area. The west to east oriented Nebraska-Kansas state line is located near the figure 2 south edge. York, Seward. Lancaster, Fillmore, Saline, Gage. Thayer, and Jefferson are Nebraska county names and the county boundaries are shown. The Big Blue River flows in a south-southeast direction from eastern Seward County to Crete in northeast Saline County and then to De Witt in southeast Saline County. From De Witt the Big Blue River flows in a southeast direction to Beatrice in central Gage County and then to Wymore and the Kansas border. Once in Kansas the Big Blue River flows in a south-southwest direction to the figure 2 south edge. The Little Blue River flows in a southeast direction from the figure 2 west edge to Hebron in central Thayer County and then turns to flow in an east-northeast direction to Powell in western Jefferson County. At Powell the Little Blue River turns to flow in a southeast direction to Fairbury, Endicott, and Steele City before reaching the Kansas border. The Little Blue River joins the Big Blue River south of the figure 2 map area. Turkey Creek flows in a northeast direction in western Fillmore County and then turns to flow in a southeast direction before turning to flow in a northeast direction into northern Saline County. After flowing in an east direction to near Pleasant Hill, Turkey Creek turns to flow in a south-southeast direction to join east-northeast Swan Creek and then the south-oriented Big Blue River near De Witt in southeast Saline County. Note how Big Blue River tributaries from the east are generally short and are southwest or south oriented while Big Blue River tributaries from the west are long and frequently have northeast oriented valley segments and/or northeast and even north oriented tributaries. East of the south-southeast oriented Big Blue River valley is the southeast-oriented Big Nemaha River drainage basin. Other essays have established the Big Nemaha River valley and tributary valleys eroded headward from the actively eroding Missouri River valley to capture south- and southeast-oriented flood water and to divert the flood water to the newly eroded Missouri River valley. Headward erosion of the Big Blue River valley beheaded some southeast-oriented flood flow routes to the actively eroding Big Nemaha River valley system and diverted flood water south to the Kansas River valley. Tributary valleys eroded west from the actively eroding Big Blue River valley head in sequence. In terms of the major tributary valleys discussed here the Little Blue River valley eroded headward or west first. Headward erosion of the Little Blue River valley was followed by Big Indian Creek valley formation (described in figures 9 and 10 below), which beheaded some flood flow routes to the newly eroded Little Blue River valley. Next the Cub Creek valley eroded headward or west and beheaded flood flow routes to the newly created Big Indian Creek valley. The Swan Creek valley then eroded headward or west and beheaded flood flow routes to the newly eroded Cub Creek valley. Finally the Turkey Creek valley eroded headward or west and beheaded flood flow routes to the newly eroded Swan Creek valley. Topographic maps below begin in the north and proceed south to document evidence supporting the erosion sequence described here.

Turkey Creek-Swan Creek drainage divide area

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

Figure 3 uses reduced size topographic maps to illustrate the Turkey Creek-Swan Creek drainage divide area in eastern Fillmore and in Saline County, Nebraska. Crete is the town located in the figure 3 northeast corner. De Witt is the town located in the southeast corner. Wilber is the town located north of De Witt and south of Crete. The Big Blue River flows south from Crete to Wliber, De Witt, and the figure 3 east edge. Exeter is the town located in the figure 3 northwest corner. Turkey Creek flows in a southeast direction from the figure 3 west edge to join northeast oriented South Fork Turkey Creek and then to flow in a northeast direction to the figure north center area. After flowing in an east direction across the figure 3 north center area Turkey Creek turns to flow in a south-southeast direction to join east-northeast oriented Swan Creek in the figure 3 southeast corner and flow to the south-southeast oriented Big Blue River near De Witt. Note how Swan Creek tributaries from the north are almost all southeast-oriented. The longest Swan Creek tributary is the North Fork Swan Creek, which originates as a north and north-northeast oriented stream and then makes a U-turn near the figure 3 center to flow in a southeast direction to join east-northeast oriented Swan Creek. The north and north-northeast oriented North Fork Swan Creek valley segment was probably eroded by a reversal of flood flow on the north end of a south-oriented flood flow channel beheaded by headward erosion of the southeast-oriented North Fork Swan Creek valley. Note north- and northwest-oriented tributaries to the northeast-oriented South Fork Turkey Creek valley west of the North Fork Swan Creek headwaters area. Those north- and northwest-oriented tributary valleys were probably eroded by reversals of flood flow on the north and northwest ends of beheaded south- and southeast-oriented flood flow channels. Figure 3 evidence suggests south-oriented flood flow initially moved across the entire figure 3 map area on a topographic surface at least as high as the highest figure 3 elevations today. Headward erosion of the deep Big Blue River valley into the figure 3 map area southeast corner permitted the Swan Creek valley to erode west capture south-oriented flood flow and the Big Blue River valley and Turkey Creek valley to erode north along south-oriented flood flow channels. At the same time the North Fork Swan Creek valley eroded headward to capture south-oriented flood flow west of the actively eroding Turkey Creek valley. The Turkey Creek valley was able to erode headward faster than the North Fork Swan Creek valley and was able to turn and erode in a west direction to behead south-oriented flood flow to the North Fork Swan Creek. The turn in the Turkey Creek valley orientation may have resulted from the beheading of south-oriented flood flow on the south-oriented Turkey Creek alignment (by Big Blue River tributary valleys north of the figure 3 map area) while southeast-oriented flood water continued to flow in from the northwest. Headward erosion of the Turkey Creek valley then continued in a southwest direction to behead the southeast-oriented flood flow routes to what was then the actively eroding Swan Creek valley system. Another interpretation is the northeast-oriented Turkey Creek valley originated as a southwest-oriented flood flow channel, which was beheaded and reversed by Turkey Creek valley headward erosion. Figure 4 below provides a detailed map of the Dry Branch Turkey Creek-North Fork Swan Creek drainage divide area just north of where the North Fork Swan Creek makes its U-turn.

Detailed map of Dry Branch Turkey Creek-North Fork Swan Creek drainage divide area

Figure 4: Detailed map of Dry Branch Turkey Creek-North Fork Swan Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 4 provides a detailed map of the Dry Branch Turkey Creek-North Fork Swan Creek drainage divide area seen in less detail in figure 3 above. Dry Branch Turkey Creek drains from the figure 4 west edge across the figure 4 northwest quadrant to the figure 4 north edge. Other north-oriented drainage flows to the northeast-oriented Dry Branch Turkey Creek. The North Fork Swan Creek flows north from the figure 4 south edge (west half) and then makes a U-turn to flow in a southeast direction to the figure 4 south center edge. Other figure 4 south oriented drainage flows to southeast-oriented North Fork Swan Creek. The Dry Branch Turkey Creek-North Fork Swan Creek drainage divide area is relatively flat, although some minor undulations suggest the presence of shallow flood eroded channels that existed prior to headward erosion of the deep Dry Branch Turkey Creek valley. Lack of deep flood flow channels suggests south oriented flood flow moving across the figure 4 area was moving as sheets of water, rather than in anastomosing channel complexes. The sheets of south oriented flood flow were first being captured by headward erosion of the deep southeast-oriented North Fork Swan Creek valley. Apparently headward erosion of the North Fork Swan Creek valley beheaded a major south-oriented flood flow route in the section 34 area and triggered a reversal of flood flow. The reversal of flood flow eroded the north-oriented North Fork Swan Creek valley. Yet to beheaded flood waters from west of the actively eroding North Fork Swan Creek valley head provided the water volumes needed to erode the deep north-oriented North Fork Swan Creek valley. Headward erosion of the Dry Branch Turkey Creek valley north of the figure 4 map area was probably occurring at approximately the same time. The northeast-oriented Dry Branch Turkey Creek valley eroded headward from the newly eroded Turkey Creek valley to behead all flood flow routes to the actively eroding southeast-oriented North Fork Swan Creek valley (which explains why the North Fork Swan Creek valley did not erode further to the northwest). The North Fork Swan Creek valley did erode south and south-southwest from the figure 4 map area to capture south- and southeast-oriented flood flow that had yet to be beheaded by Turkey Creek headward erosion. Turkey Creek headward erosion then beheaded all flood flow routes to the actively eroding north-oriented North Fork Swan Creek valley.

Swan Creek-Cub Creek drainage divide area

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

Figure 5 also uses reduced size topographic maps to illustrate the Swan Creek-Cub Creek drainage divide area south of the figure 3 map area and includes overlap areas with figure 3. The urban area along the figure 5 east center edge area is the western edge of the Beatrice, Nebraska urban area. The Big Blue River flows in a southeast direction from the figure 5 north edge to Beatrice and the figure 5 east edge. De Witt is the smaller town northwest of Beatrice in the Big Blue River valley. Swan Creek is the east-northeast stream flowing from the figure 5 northwest quadrant to join south oriented Turkey Creek just west of De Witt and then to flow to the southeast-oriented Big Blue River. Fairbury, Nebraska is the town located along the figure 5 south edge (west half). The southeast-oriented river flowing across the figure 5 southwest corner and to Fairbury is the Little Blue River. The east, northeast, and east oriented Big Blue River tributary originating north of Fairbury and joining the Big Blue River northwest of Beatrice is Cub Creek. Note how Cub Creek has south and southeast oriented tributaries from the north and north and northwest oriented tributaries from the south. Also note how tributaries from the north are short and east-oriented just west of the Big Blue River. Headward erosion of the deep Big Blue River valley and east and northeast oriented tributary valleys immediately north of the newly eroded Cub Creek valley limited the ability of Cub Creek tributary valleys to erode north or northwest in that area, although flood flow from the west was still able to reach the newly eroded and deep Cub Creek valley (which accounts for the east-oriented tributary). Further away from the Big Blue River valley south and southeast oriented Cub Creek tributary valleys were able to erode headward until headward erosion of the Swan Creek valley and northeast oriented Swan Creek tributary valleys beheaded south oriented flood flow routes to the actively eroding Cub Creek tributary valleys. North and northwest oriented Cub Creek and Swan Creek tributary valleys were eroded by reversals of flow on north and northwest ends of beheaded south oriented flood flow routes. Swan Creek valley headward erosion (actually South Fork Swan Creek valley headward erosion) beheaded all south and southeast-oriented flood flow routes to what had been the actively eroding Cub Creek valley. Prior to that time Cub Creek valley headward erosion was beheading south oriented flood flow to actively eroding south oriented Little Blue River tributary valleys.

Detailed map of Swan Creek-Cub Creek drainage divide area

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

Figure 6 provides a detailed map of the drainage divide between an unnamed South Fork Swan Creek tributary and the Cub Creek valley system, which was seen in less detail in figure 5 above (the figure 6 map area is located slightly north of the Cub Creek headwaters area). Cub Creek flows in northeast direction from the figure 6 south center edge and then turns to flow in an east-southeast direction to the figure 6 south edge (east half). An east-southeast oriented Cub Creek tributary drains from the figure 6 west edge area to the figure 6 south center edge area and the northeast and east-southeast oriented Cub Creek valley. Note southeast and south oriented Cub Creek tributaries draining the figure 6 southeast half. The figure 6 northwest half is drained by a southeast, northeast, southeast, and northeast oriented South Fork Swan Creek tributary. Note northeast, north, and northwest oriented tributaries to the South Fork Swan Creek tributary valley. Figure 6 drainage divide elevations rise slightly toward the west. Figure 6 drainage history begins with southeast and south oriented flood water moving across the entire figure 6 map area, with flood water erosion being somewhat greater in the east than in the west. Flood waters were flowing on a topographic surface at least as high as the highest present day figure 6 elevations and flood waters were eroding the entire figure 6 map area (lowering the regional elevations). Headward erosion of the deep east-oriented Cub Creek valley from what was then the deep south-oriented Big Blue River valley captured the southeast and south oriented flood water and diverted the flood flow east to the newly eroded south-oriented Big Blue River valley. South and southeast oriented Cub Creek tributary valleys eroded headward from the actively eroding Cub Creek valley head. Next headward erosion of the deep Swan Creek-South Fork Swan Creek valley (north of the figure 6 map area) beheaded south-oriented flood flow to the newly eroded Cub Creek valley. Flood waters on north ends of beheaded flood flow routes reversed flow direction to flow north to the newly eroded South Fork Swan Creek valley. The north-oriented South Fork Swan Creek tributary valleys in figure 6 were eroded by such reversals of flood flow. The flood flow reversals also created the Swan Creek-Cub Creek drainage divide.

Cub Creek-Big Indian Creek drainage divide area

Figure 7: Cub Creek-Big Indian Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 7 again uses reduced size topographic maps to illustrate the Cub Creek-Big Indian Creek drainage divide area south of the figure 5 map area and includes overlap areas with figure 5. Beatrice is the city located in the figure 7 northeast quadrant. The Big Blue River flows in a southeast direction from the figure 7 north edge to Beatrice and then in a south-southeast direction to Blue Springs and Wymore, Nebraska before flowing to the figure 7 east edge (Blue Springs is immediately north of Wymore). The northeast oriented stream joining the southeast-oriented Big Blue River at Wymore is Big Indian Creek. Big Indian Creek originates near Diller in the figure 7 south center area and flows in a southeast direction to Odell before making an abrupt turn to flow in a northeast direction to join the Big Blue River near Wymore. Fairbury is the smaller city located near the figure 7 west edge. Note the prominent south and southeast oriented Big Indian Creek tributaries. Also the north-northwest oriented Big Indian Creek tributary located in the figure 7 southeast corner area. The Little Blue River is the southeast-oriented river flowing across the figure 7 southwest quadrant and next to Fairbury. The east, northeast, and east oriented stream originating north of Fairbury and joining the Big Blue River northwest of Beatrice is Cub Creek. Figure 7 drainage history begins with southeast-oriented flood flow moving across the entire figure 7 map area on a topographic surface higher than the highest present day figure 7 elevations. Flood waters were probably flowing to what was then the actively eroding deep Big Blue River valley head located south and east of the figure 7 map area. The deep Little Blue River valley eroded headward from the actively eroding Big Blue River valley and both deep valleys eroded headward into the figure 7 map area. The northeast-oriented Big Indian Creek valley probably was initiated as a southwest-oriented flood flow channel to a valley south of the figure 7 map area (see figure 9 and 10 below) and was beheaded and reversed by Big Blue River valley headward erosion. Flood waters on north ends of beheaded flood flow routes reversed flow direction to erode north- and north-northwest oriented Big Indian Creek valleys. South and southeast oriented tributary valleys eroded headward from this actively eroding [present day northeast-oriented] Big Indian Creek valley. Continued Big Blue River valley headward erosion permitted the Cub Creek valley to erode headward (to the west and southwest) to capture south and southeast oriented flood flow routes to the actively eroding Big Indian Creek tributary and headwaters valleys. Flood waters on north ends of beheaded flood flow routes reversed flow direction to erode north-oriented Cub Creek tributary valleys and to create the present day Cub Creek-Big Indian Creek drainage divide. Note the south-southeast oriented Big Blue River tributary originating south of Beatrice and joining the Big Blue River near Wymore. That stream is Bills Creek and figure 8 below provides a detailed map of the Big Blue River-Bills Creek drainage divide area.

Detailed map of Big Blue River-Bills Creek drainage divide area

Figure 8: Detailed map of Big Blue River-Bills Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 8 provides a detailed map of the Big Blue River-Bills Creek drainage divide area south of Beatrice and which can be seen in less detail in figure 7 above. Beatrice is located north of the figure 8 map area with the south edge of town being located in the figure 8 north center edge area. The Big Blue River flows in an east direction just north of the figure 8 map area from Beatrice to the figure 8 northeast corner area and then meanders in a south-southeast direction along the figure 8 east edge. North-oriented drainage in the figure 8 north half flows to the Big Blue River. Bills Creek is the south-oriented stream flowing to the figure 8 south center edge. Note northeast-oriented Bills Creek headwaters in section 21 and how Bills Creek makes a U-turn from flowing in a northeast direction to flowing in a south-southeast direction. South of the figure 8 map area Bills Creek flows in a south-southeast direction to join the Big Blue River near Wymore. The south-southwest oriented stream flowing to the figure 8 southwest corner eventually flows to northeast-oriented Big Indian Creek (see figure 7). Note north-south oriented through valleys linking the north-oriented Big Blue River tributary valleys with the south-oriented Bills Creek and Big Indian Creek tributary valleys. Perhaps the easiest through valley to see is used by the railroad in section 22. That through valley is 20-30 feet deep and links a north-oriented Big Blue River tributary valley with the south-oriented Bills Creek valley. Another interesting through valley is located in section 19 (near the figure 8 west edge in the southwest quadrant) and links a north-northeast oriented Big Blue River tributary valley with the south-oriented Big Indian Creek tributary valley and is also 20-30 feet deep. Both through valleys and other shallower through valleys are evidence of south-oriented flood flow across the figure 8 map area to what were then the actively eroding south-oriented Bills Creek and Big Indian Creek tributary valleys. Flood water flowing in the through valleys at that time had not yet been beheaded by headward erosion of the deep Big Blue River valley. Headward erosion of the Big Blue River valley beheaded the south-oriented flood flow channels (from east to west). Flood waters on north ends of  beheaded flood flow channels reversed flow direction to flow north to the newly eroded and deeper Big Blue River valley. The flood flow reversal eroded the north-oriented Big Blue River tributary valleys and created the Big Blue River-Bills Creek and Big Blue River-Big Indian Creek drainage divides.

Big Indian Creek-Horseshoe Creek drainage divide area

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

Figure 9 again uses reduced size topographic maps to illustrate the Big Indian Creek-Horseshoe Creek drainage divide area south of the figure 7 map area and includes overlap areas with figure 7. Marysville, Kansas is the city located in the figure 9 southeast corner. The Big Blue River flows in a southeast direction across the figure 9 northeast corner and then turns to flow in a south-southwest direction to Marysville and the figure 9 south edge. Northeast-oriented Big Indian Creek joins the Big Blue River just north of the figure 9 northeast corner. Note northwest and north oriented Big Indian Creek tributaries. Big Indian Creek flows in a southeast direction from the figure 9 north center edge to Odell, Nebraska before making a right angle turn to flow in a northeast direction. The west to east oriented Nebraska-Kansas state line is located a short distance south of Odell. Horseshoe Creek is the south, east, and southeast oriented Big Blue River tributary flowing through Independence Township (Kansas) in the figure 9 center and joining the Big Blue River north of Marysville. Note several south-oriented Horseshoe Creek tributaries. The south-southeast oriented Horseshoe Creek tributary originating south of Odell, Nebraska is Little Indian Creek. Figure 10 below provides a detailed map of the Big Indian Creek-Little Indian Creek drainage divide area and documents a large north-south oriented through valley crossing the present day drainage divide. Presence of the through valley suggests large volumes of south-oriented flood water moved from the present day Big Indian Creek drainage basin to what was then the newly eroded Horseshoe Creek valley. Probably the present day northeast-oriented Big Indian Creek valley segment originated as a southwest-oriented flood flow channel. Headward erosion of the Big Blue beheaded that southwest-oriented flood flow channel and caused a flood flow reversal that created the southeast and northeast oriented Big Indian Creek valley seen today. The Little Blue River is the stream flowing from the figure 9 northwest corner in a southeast and south direction to the figure 9 south center edge. Endicott, Nebraska is the town in the Little Blue River valley in the figure 9 northwest corner. Steele City, Nebraska is located in the Little Blue River valley southeast from Endicott and is near the Nebraska-Kansas border. Hollenberg, Kansas is southeast from Steele City and Hanover, Kansas is the Little Blue River valley town located in the figure 9 south center area. Figure 9 drainage history again begins with south-oriented flood water moving across the figure 9 map area. Headward erosion of deep Big Blue River and Little Blue River valleys next began to capture the south-oriented flood flow. The Horseshoe Creek valley eroded headward (or northwest) from the actively eroding Big Blue River valley head location at that time to capture south-oriented flood flow between the actively eroding Little Blue River valley and Big Blue River valley. South-oriented Horseshoe Creek tributary valleys eroded north from the newly eroded Horseshoe Creek valley. The southeast and northeast oriented Big Indian Creek valley probably originated as a southeast and southwest oriented flood flow channels to the newly eroded south-oriented Little Indian Creek valley (and Horseshoe Creek valley). Headward erosion of the deep Big Blue River valley beheaded and reversed the southwest-oriented flood flow channel, which then captured the southeast-oriented flood flow channel to create the Big Indian Creek valley.

Big Indian Creek-Little Indian Creek drainage divide area

Figure 10 provides a more detailed map of the Big Indian Creek-Little Indian Creek drainage divide area south of Odell, Nebraska and seen in less detail in the figure 9 map area. The west to east oriented Nebraska-Kansas state line is located north of the figure 10 south edge. Big Indian Creek is the southeast oriented stream flowing from the figure 10 north edge west of Odell and turning to flow in a northeast and north direction to the figure 10 north edge east of Odell. Little Indian Creek is the northwest-oriented stream in section 29, which turns to flow in a southwest and south direction to the figure 10 south center edge. The Big Indian Creek-Little Indian Creek drainage divide area appears to be a relatively flat surface at an elevation of slightly more than 1350 feet (and less than 1360 feet). A close look at figure 10 evidence shows elevations rise both to the east and west. Continuing east and west of the figure 10 map area elevations rise to approximately 1450 feet on both sides, suggesting a broad north-south valley several miles in width and approximately 100 feet deep links the southeast-northeast oriented Big Indian Creek valley with the south oriented Little Indian Creek valley and the southeast-oriented Horseshoe Creek valley. This large north-south oriented through valley was eroded by massive south oriented flood flow, some of which may have been moving in a southwest and south direction along the present day northeast oriented Big Indian Creek valley alignment. Flood water was probably moving south to what was then the newly eroded deep southeast-oriented Horseshoe Creek valley, which had eroded headward from the actively eroding Big Blue River valley head. At that time the Big Blue River valley had not yet eroded headward to behead south and southwest-oriented flood flow moving on the present day northeast oriented Big Indian Creek valley alignment. When headward erosion of the deep Big Blue River valley did behead the southwest-oriented flood flow channel flood water on the north end of the beheaded flood flow channel reversed flow direction to flow in a northeast direction to erode the present day deep northeast oriented Big Indian Creek valley. That flood flow reversal captured the southeast oriented flood flow channel that is now the southeast-oriented Big Indian Creek valley segment upstream from Odell. The deep Big Indian Creek valley (which eroded headward from the deep Big Blue River valley) eroded headward along the captured northeast- and southeast-oriented flood flow channels to create the present day southeast- and northeast-oriented Big Indian Creek valley. Figure 10 evidence provides a minimal measure of the magnitude of flood flow involved and suggests other drainage divides were eroded by comparable flood water volumes.

Additional information and sources of maps

This essay has only provided a sample of the drainage divide evidence supporting the “thick ice sheet that melted fast” geomorphology paradigm. Many additional examples could be provided, especially by using more detailed topographic maps. Readers are encouraged to look at mosaics of detailed topographic maps to see the abundance of supporting data. Maps used in this study were created by the United States Geological Survey and can be purchased in hard copy from the United States Geological Survey or from dealers offering United States Geological Survey maps. Hard copy maps can also be observed at United States Geological Survey map depositories located in major research libraries and elsewhere throughout the United States and in other countries. Illustrations used in this essay were created using National Geographic Society TOPO software and digital data. National Geographic Society digital maps can be purchased from the National Geographic Society or from dealers offering National Geographic Society digital maps.