The Platte River-Missouri River drainage divide area in Cass, Lancaster, and Otoe Counties, Nebraska was eroded by massive southeast and south oriented floods at the time the deep Missouri River valley eroded headward into the region. Flood waters were probably melt water floods from a rapidly melting thick North American ice sheet located north of the Platte River-Missouri River drainage divide area. Headward erosion of the deep south oriented Missouri River valley enabled the southeast-oriented Little Nemaha River valley to erode headward from the Missouri River valley west wall to capture southeast-oriented flood flow west of the newly eroded Missouri valley. Next headward erosion of the Weeping Water Creek valley beheaded south oriented flood flow routes to the newly eroded Little Nemaha River valley. Finally headward erosion of the east-northeast oriented Platte River valley and its northeast-oriented Salt Creek tributary valley beheaded all south- and southeast-oriented flood flow routes to what were then actively eroding Weeping Water Creek and Little Nemaha River valley systems. Evidence supporting this interpretation includes valley orientations and shallow through valleys crossing present day drainage divides.

Preface:

• The purpose of this essay is to use topographic map interpretation methods to explore Platte River-Missouri River drainage divide area landform origins in Cass, Lancaster, and Otoe 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 Platte River-Missouri River drainage divide area landform origins in Cass, Lancaster, and Otoe 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.

Platte River-Missouri River drainage divide area location map

Figure 1: Platte River-Missouri 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 Platte River-Missouri River drainage divide area location map and illustrates southeast Nebraska, northeast Kansas, northwest Missouri, and southwest Iowa. Nebraska is the state in the figure 1 northwest quadrant, Kansas is located in the southwest, Missouri is located in the southeast, and Iowa is located in the northeast. The Missouri River flows in a south-southeast direction from the figure 1 north edge along the Nebraska-Iowa border to Kansas City, Missouri (located near the figure 1 south edge). At Kansas City the Missouri River turns to flow in an east-northeast direction to the figure 1 east edge. The Platte River flows in a northeast direction in the figure 1 northwest corner to Columbus and then gradually turns to flow south to Ashland. Near Ashland the Platte River turns again to flow in an east-northeast direction to join the Missouri River at Plattsmouth. Salt Creek is an unlabeled stream flowing in a northeast direction from Lincoln, Nebraska to join the Platte River near Ashland. The Little Nemaha River originates southeast of Lincoln and flows through Syracuse, Talmage, and Brock before joining the Missouri River south of Brownville, Nebraska. The Platte River-Missouri River drainage divide area illustrated and discussed in this essay is located south of the Platte River, southeast of Salt Creek, northeast of the Little Nemaha River, and west of the Missouri River. Other essays addressed the Elkhorn River-Missouri River, Platte River-Wahoo Creek and Platte River-Salt Creek drainage divide areas north and northwest of the Platte River-Missouri River drainage divide area discussed here and can be found under Platte River on the sidebar category list. These and hundreds of other Missouri River drainage basin landform origins research project essays published on this website describe immense southeast and south-southeast oriented melt water floods, which flowed from a rapidly melting thick North American ice sheet to and across Nebraska. The Missouri River valley and its tributary valleys eroded headward to capture this immense south-southeast and southeast oriented flood flow and to divert flood waters east to the south-oriented Mississippi River valley (located east of the figure 1 map area). The Little Nemaha River valley eroded headward from the actively eroding Missouri River valley west wall to capture flood waters west of the newly eroded Missouri River valley. Next the Platte River valley and its tributary Salt Creek valley eroded west and southwest to behead southeast and south-southeast oriented flood flow to the actively eroding Little Nemaha River valley. Headward erosion of the Platte River valley to the north and west then beheaded flood flow routes to the newly eroded Salt Creek valley.

Platte River-Missouri River drainage divide area detailed location map

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

Figure 2 provides a somewhat more detailed location map for the Platte River-Missouri River drainage divide area. Seward, Lancaster, Sarpy, Cass, Otoe, Saline, Gage, Johnson, and Nemaha are Nebraska county names and county boundaries are shown. The Missouri River is the south and south-southeast oriented river located near the figure 2 east edge. Iowa is the state located east of the Missouri River. The Platte River forms the west and south Sarpy County borders (in the figure 2 northeast quadrant). Salt Creek flows in a northeast direction from Lincoln to join southeast oriented Wahoo Creek near Ashland and then flow to the nearby Platte River. Hooper Creek in the Otoe County northwest corner (and in adjacent Lancaster County) flows in a northeast direction before turning to flow in a southeast direction to join the southeast-oriented Little Nemaha River, which flows into Nemaha County and joins the Missouri River at Nemaha (in the figure 2 southeast corner). Note the southeast and south oriented North Fork Little Nemaha River west of Nebraska City. In Cass County note east and southeast oriented Weeping Water Creek, which joins the Missouri River near the Cass County-Otoe County line. Most Missouri River tributaries in the Platte River-Missouri River drainage divide area are southeast-oriented or have significant southeast-oriented valley segments. Rock Creek in eastern Cass County is an exception and flows in a northeast and east direction to join the south-oriented Missouri River at Rock Bluff. Most Platte River tributaries in the drainage divide area are north oriented and most Salt Creek tributaries are northwest or north oriented. The north oriented tributaries to what is a south-oriented Missouri River drainage basin were eroded by reversals of flood flow on the north ends of beheaded flood flow routes. Flood waters on the north ends of those beheaded flood flow routes reversed flow direction to flow north to the newly eroded and deeper valleys, which had beheaded the south-oriented flood flow routes. For example, northwest-oriented tributary valleys to the northeast-oriented Salt Creek valley were eroded by reversals of flood flow on the northwest ends of beheaded southeast-oriented flood flow channels. Headward erosion of the deep valleys beheaded one channel at a time and flood flow channels were anastomosing (or interconnected). Reversed flood flow in a newly beheaded channel could often capture significant yet to be beheaded flood flow from flood flow channels further to the west. Captures of such yet to be beheaded flood flow provided the water volumes necessary to erode significant north and northwest oriented tributary valleys.

Platte River-Missouri River drainage divide area near Plattsmouth

Figure 3: Platte River-Missouri River drainage divide area near Plattsmouth. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 3 illustrates the Platte River-Missouri River drainage divide area near Plattsmouth. The south-southeast oriented Missouri River is located in the figure 3 northeast corner. The Platte River flows in a northeast and east direction in the figure 3 north half and joins the Missouri River in the figure 3 northeast corner. Plattsmouth is the town located in the figure 3 northeast quadrant and Louisville is the smaller town located in the northwest quadrant. Manley is the still smaller town located in the figure 3 southwest quadrant. Rock Bluff is the even smaller town located in the southeast quadrant along the figure 3 east edge. Southeast and south oriented drainage along the figure 3 south edge flows to southeast-oriented Weeping Water Creek, which in turn flows to the Missouri River. West of Plattsmouth, Fourmile Creek and its tributary Eightmile Creek flow in a generally north direction to reach the east-oriented Platte River. Boundaries between different scanned maps do not properly mesh, however it is possible to see significant northwest-oriented Fourmile and Eightmile Creek segments, along with north and northeast oriented segments. The northwest oriented valley segments were eroded by reversals of flood flow on the northwest ends of beheaded southeast-oriented flood flow routes. Further west Turkey Creek flows in a northwest direction to reach the northeast-oriented Platte River. West of Turkey Creek is north and northwest oriented Cedar Creek. Mill Creek, which flows north to Louisville is linked by through valleys in the Manley area with southeast-oriented South Cedar Creek. Note also that north-oriented Cedar Creek headwaters are also linked by through valleys to south oriented valleys draining to the southeast-oriented South Cedar Creek valley. South Cedar Creek flows to southeast-oriented Weeping Water Creek. Figure 4 below provides a detailed map of drainage divides near Manley to better illustrate the north-south oriented through valleys linking north-oriented Platte River tributary valleys with south and southeast oriented Weeping Water Creek tributary valleys. These through valleys along with the tributary orientations provide evidence the Platte River valley eroded headward across the figure 3 map area to capture (and beheaded) multiple south and southeast oriented flood flow channels, such as might be found in a south- or southeast-oriented anastomosing channel complex. Flood waters on the north ends of the beheaded flood flow channels reversed flow direction to flow north to newly eroded and deeper Platte River valley.

Detailed map of Platte River-Weeping Water Creek drainage divide area near Manley

Figure 4: Detailed map of Platte River-Weeping Water Creek drainage divide area near Manley. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 4 provides a detailed map of the Mill Creek-South Cedar Creek drainage divide area at and near Manley, which was seen in less detail in figure 3 above. South Cedar Creek originates in section 16 near the figure 4 west center edge and flows in a northeast direction before turning to flow in a southeast direction across section 15 and section 23 to the figure 4 south center edge. From the figure 4 south edge South Cedar Creek flows to southeast-oriented Weeping Water Creek, which flows to the Missouri River. The north-oriented valley extending north from Manley along the section 10-11 boundary is the headwaters valley of north-oriented Mill Creek, flows to the northeast-oriented Platte River at Louisville. Note how the north-oriented Mill Creek valley is linked by a north-south oriented through valley at Manley with a south-oriented South Cedar Creek tributary valley. The through valley provides evidence flood water once flowed south along the Mill Creek alignment to what was then the actively eroding South Cedar Creek valley (and Weeping Water Creek valley). South-oriented flood flow in the through valley ended when headward erosion of the deep Platte River valley beheaded the south-oriented flood flow channel. Flood waters on the north end of the beheaded flood flow channel reversed flow direction to flow north to the newly eroded and deeper Platte River valley. The reversal of flood flow eroded the north-oriented Mill Creek valley and created the Mill Creek-South Cedar Creek drainage divide. The north-oriented stream in sections 7, 18, and 19 along the figure 4 east edge is north-oriented Cedar Creek, which also flows to the northeast-oriented Platte River (see figure 3). The south-oriented stream in the figure 4 southeast corner (originating in figure 19 south half) flows in a southeast direction to join southeast-oriented South Cedar Creek, with water eventually flowing to Weeping Water Creek and then to the Missouri River. Note the north-south oriented through valley in section 19 linking the north-oriented Cedar Creek valley with the south-oriented South Cedar Creek tributary valley. The through valley is further evidence of south-oriented flood flow across the figure 4 map area. Flood waters initially flowed south on a topographic surface at least as high as the highest figure 4 elevations today. Multiple through valleys provide evidence of multiple south-oriented flood flow channels, such as might be found in a south-oriented anastomosing channel complex. Headward erosion of the deep Platte River valley beheaded the south-oriented flood flow channels, which at that time were moving flood waters to the newly eroded Weeping Water Creek and tributary valleys.

Salt Creek-Weeping Water Creek drainage divide area

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

Figure 5 uses reduced size maps to illustrate the Salt Creek-Weeping Water Creek drainage divide area west of the figure 3 map area and includes overlap areas with figure 3. The southeast and northeast oriented Platte River is located in the figure 5 northeast quadrant. Louisville is the town located in the figure 5 northeast corner area. Salt Creek is the northeast oriented stream located in the figure 5 northwest quadrant and joins southeast-oriented Wahoo Creek north of the figure 5 map area. Wahoo Creek in turn joins the Platte River north of the figure 5 map area. The Salt Creek channel has been modified and is not always located in its original location. Greenwood is the town located in the Salt Creek valley. Elmwood is the town located near the figure 5 south center edge. Weeping Water Creek flows in a northeast direction from Elmwood and then turns to flow in an east direction, with a jog to the north and back south to the figure 5 east edge. The town located  next to Weeping Water Creek along the figure 5 east edge is Weeping Water. Note northwest-oriented tributaries to the northeast-oriented Salt Creek valley and southeast-oriented tributaries to the Weeping Water Creek valley. Also note north-northwest and north oriented tributaries to the Platte River. A close look at figure 5 reveals through valleys linking north- and northwest-oriented Platte River and Salt Creek tributaries with the southeast-oriented Weeping Water Creek tributaries (more detailed topographic maps show the through valleys better). What has happened here is prior to headward erosion of present day valleys south and southeast oriented flood waters flowed across the entire figure 5 map area, probably to what was then the actively eroding south-oriented Missouri River valley. The Weeping Water Creek valley then eroded headward  from that newly eroded Missouri River valley to capture southeast-oriented flood flow west of the newly eroded Missouri River valley. Next headward erosion of the Platte River valley beheaded south-oriented flood flow routes to the newly eroded Weeping Water Creek valley, although the Weeping Water Creek valley then eroded to the southwest to capture southeast oriented flood flow still moving to the newly eroded Missouri River valley. Next headward erosion of the northeast-oriented Salt Creek valley beheaded the southeast-oriented flood flow routes to the newly eroded Weeping Water Creek valley. Flood waters on the northwest ends of the beheaded flood flow routes reversed flow direction to erode northwest-oriented Salt Creek tributary valleys and to create the present day Salt Creek-Weeping Water Creek drainage divide.

Salt Creek-Hooper Creek drainage divide area

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

Figure 6 illustrates the Salt Creek-Hooper Creek drainage divide area west and south of the figure 5 map area. Lincoln is the city located along the figure 6 west edge. Elmwood is the town located in the figure 6 east center area. Eagle is the small town located in the figure 6 center area. Salt Creek is the northeast-oriented stream located in the figure 6 northwest quadrant. Note the northwest-oriented Salt Creek tributaries. Weeping Water Creek flows in a northeast direction from Elmwood and then turns to flow in an east direction to the figure 6 east edge. Note southeast oriented Weeping Water Creek tributaries or tributary segments. The southeast, east, and southeast oriented stream located south of Eagle is Hooper Creek. Hoooper Creek flows from the figure 6 map area to the southeast-oriented Little Nemaha River seen in figures 8 and 10 below. Note the southeast oriented Hooper Creek tributaries. A close look at figure 6 reveals through valleys linking the northwest oriented Salt Creek tributary valleys with the southeast oriented Weeping Water Creek and Hooper Creek tributary valleys. Again more detailed maps show the through valleys better and figure 7 below provides a detailed map of the Salt Creek-Hooper Creek drainage divide area near Eagle. Again what has happened here is prior to headward erosion of present day valleys southeast-oriented flood waters flowed across the entire figure 6 map area on a topographic surface at least as high as the highest figure 6 elevations today. Flood waters were probably flowing to what was then the newly eroded Missouri River valley and the actively eroding southeast-oriented Little Nemaha River valley, which was eroding headward from the newly eroded Missouri River valley. The Hooper Creek and Weeping Water Creek valleys probably eroded headward into the figure 6 map area at about the same time. Note how the two valleys captured different southeast-oriented flood flow routes. Next headward erosion of the Platte River-Salt Creek valley beheaded the southeast-oriented flood flow routes to the actively eroding Weeping Water Creek and Hooper Creek valleys. Flood waters on the northwest ends of the beheaded flood flow routes reversed flow direction to flow in a northwest direction to the newly eroded and deeper Salt Creek valley. This reversal of flood flow was responsible for eroding the northwest-oriented Salt Creek tributary valleys and for creating the Salt Creek-Hooper Creek drainage divide.

Detailed map of Salt Creek-Hooper Creek drainage divide area near Eagle

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

Figure 7 provides a detailed map of the Salt Creek-Hooper Creek (Little Nemaha River) drainage divide area near Eagle. Camp Creek is the northwest oriented Salt Creek tributary in section 16. Other north-oriented drainage routes in the figure 7 north half are Camp Creek tributaries. South and southeast oriented drainage in the figure 7 south half flows to southeast-oriented Hooper Creek, which in turn flows to the southeast-oriented Little Nemaha River. The Camp Creek-Hooper Creek drainage divide is the Platte River-Missouri River drainage divide. The Missouri Pacific Railroad line is built along the drainage divide. Follow the railroad from the figure 7 west edge to the figure 7 east edge and note the numerous shallow north-south oriented through valleys the railroad crosses. For example, the railroad crosses a shallow through valley in the section 24 south half, then again in the section 19 southwest corner and again in the section 19 southeast quadrant. Some even shallower through valleys can be seen in sections 20 and 21 and further east the railroad crosses two shallow through valleys in section 22. These shallow through valleys provide evidence that prior to Salt Creek valley headward erosion (northwest of the figure 7 map area) multiple southeast-oriented flood flow channels flowed across the figure 7 map area to what was then the actively eroding Hooper Creek tributary valley system. Headward erosion of the northeast-oriented Salt Creek valley (from what was then the newly eroded Platte River valley) beheaded southeast-oriented flood flow to the actively eroding Hooper Creek drainage basin. Flood waters on the northwest and north ends of the beheaded flood flow channels reversed flow direction to flow northwest and north to the newly eroded and deeper Salt Creek valley. This reversal of flood flow was responsible for eroding the northwest and north oriented Salt Creek tributary valleys and also for creating the Platte River-Missouri River drainage divide. [Remember, Salt Creek headward erosion beheaded flood flow channels one channel at a time and flood flow channels were anastomosing. Reversed flow in a newly beheaded flood flow channel could usually capture yet to be beheaded flood flow from flood flow channels further to west. Such captured flood flow helped erode significant north-oriented valleys.]

Stevens Creek-Little Nemaha River drainage divide area

Figure 8: Stevens Creek-Little Nemaha River drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 8 illustrates the Stevens Creek-Little Nemaha River drainage divide area south and west of the figure 6 map area and includes overlap areas with figure 6. Lincoln is the city located in the figure 8 northwest corner area. Stevens Creek is the north and north-northwest oriented stream in the figure 8 northwest quadrant (just east of Lincoln). North of the figure 8 map area Stevens Creek flows to northeast-oriented Salt Creek, which flows to Wahoo Creek and the Platte River. Eagle is the small town located near the figure 8 north edge in the Cass County southwest corner. Note the southeast-oriented Hooper Creek drainage system south of Eagle. Southeast-oriented tributaries flow to an east-oriented Hooper Creek segment and then Hooper Creek turns to flow in a southeast direction to join the east-northeast oriented Little Nemaha River near the figure 8 east edge. From its confluence with Hooper Creek the Little Nemaha River flows in a southeast direction to join the Missouri River (see figure 2). Palmyra and Bennet are the towns located in the east-northeast and east oriented Little Nemaha River valley. Note southeast-oriented Little Nemaha River tributaries from the north (northeast-oriented tributaries from the south eroded headward in sequence prior to headward erosion of the east and east-northeast oriented Little Nemaha River valley segment). The north-northwest oriented Little Nemaha River tributary south of Bennet was eroded by a reversal of flood flow on the north end of a beheaded south-oriented flood flow route. The southeast-oriented Little Nemaha River tributaries and southeast-oriented Hooper Creek tributaries provide evidence the Little Nemaha River valley eroded west and west-southwest from the southeast-oriented Hooper Creek-Little Nemaha valley to capture multiple southeast-oriented flood flow channels and then the Hooper Creek valley eroded west from that same southeast-oriented Hooper Creek-Little Nemaha River alignment to behead southeast-oriented flood flow to the newly eroded east-northeast and east oriented Little Nemaha River valley. Next headward erosion of the northeast-oriented Salt Creek valley (north of figure 8) beheaded all southeast-oriented flood flow channels to the figure 8 map area. Flood waters on the north end of a beheaded south-oriented flood flow channel using the Stevens Creek alignment to reach the actively eroding Little Nemaha River valley reversed flow direction to erode the north- and north-northwest oriented Stevens Creek valley and to create the Stevens Creek-Little Nemaha River drainage divide. Figure 9 below provides a detailed map of the Stevens Creek-Little Nemaha River drainage divide area near Cheney, which is located in the figure 8 west center area southeast from Lincoln.

Detailed map of Stevens Creek-Little Nemaha River drainage divide area near Cheney

Figure 9: Detailed map of Stevens Creek-Little Nemaha River drainage divide area near Cheney. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 9 provides a detailed map of the Stevens Creek-Little Nemaha River drainage divide area near Cheney, which was seen in less detail in figure 8 above. Cheney is the town located in the figure 9 northwest quadrant. North-oriented Stevens Creek is labeled in the figure 9 northeast quadrant. Other north-oriented drainage in the figure 9 map area (east of Cheney) flows to Stevens Creek, which flows to northeast-oriented Salt Creek and the Platte River. South-oriented drainage in the figure 9 south half flows to the Little Nemaha River, which flows directly to the Missouri River. Note the railroad line, which extends from the figure 9 northwest corner in a generally southeast direction to the figure 9 southeast quadrant and east edge. For much its route across the figure 9 map area the railroad line is located on the Stevens Creek-Little Nemaha River drainage divide. The railroad line crosses several shallow through valleys eroded into that drainage divide. One such through valley is located at Cheney. Another through valley is located in the section 25 southwest corner. Still another through valley is located in the section 36 northeast quadrant. Other through valleys are located in the section 32 north half. The through valleys provide evidence of multiple south-oriented flood flow channels that moved flood waters to what was then the actively eroding Little Nemaha River valley system. At that time the Salt Creek valley (north of the figure 9 map area) and its north-oriented Stevens Creek tributary did not exist. Instead south-oriented flood water was moving to the Little Nemaha on a topographic surface at least as high as the present day Stevens Creek-Little Nemaha drainage divide. Headward erosion of the deep northeast-oriented Salt Creek valley (north of the figure 9 map area) beheaded the south oriented flood flow channels. Flood waters on the north ends of the beheaded flood flow channels reversed flow direction to flow north to the newly eroded and deeper Salt Creek valley. The reversal of flood flow eroded the north-oriented Stevens Creek valley and also created the Stevens Creek-Little Nemaha River drainage divide.

Weeping Water Creek-North Fork Little Nemaha River drainage divide area

Figure 10: Weeping Water Creek-North Fork Little Nemaha River drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

Figure 10 illustrates the Weeping Water Creek-Little Nemaha River drainage divide area east and south of the figure 8 map area. Nebraska City is the city located near the figure 10 southeast corner. The Missouri River is the south-oriented river near the figure 10 east edge. The North Fork Little Nemaha River flows in a southeast direction from the figure 10 west center edge area to the figure 10 south center edge area. Weeping Water Creek is the southeast oriented stream in the figure 10 north center area and flows to join the Missouri River in the figure 10 east center area. The South Branch Weeping Water Creek is the southeast, east, and northeast oriented Weeping Water Creek tributary flowing from the figure 10 west edge near the Cass County-Otoe County line to join Weeping Water Creek near Union in the figure 10 northeast quadrant (Union is the small town located at the northeast quadrant highway intersection). Note north oriented Weeping Water Creek (and South Branch Weeping Water Creek) tributaries and south-oriented North Fork tributaries. For example, note south-oriented Wilson Creek flowing to the North Fork Little Nemaha River in the figure 10 south center area and north-oriented Goose Creek flowing to the South Branch Weeping Water Creek, which originates just north of the Wilson Creek headwaters. Figure 10a below provides a detailed map of the Goose Creek-Wilson Creek drainage divide area. Goose Creek headwaters are located in the figure 10a northwest quadrant and Wilson Creek headwaters are located in the figure 10a southwest quadrant. Note the north-south oriented through valley linking the opposing drainage systems. Further east in figure 10a are other north-south oriented through valleys linking north-oriented Weeping Water Creek tributaries with south-oriented Little Nemaha River tributaries. These tributaries suggest the Little Nemaha River valley near the south-oriented Missouri valley eroded headward across multiple south-oriented flood flow channels to capture the south-oriented flood water and diverted that flood water to the newly eroded and deeper Missouri River valley. Subsequently headward erosion of the Weeping Water Creek-South Branch Weeping Water Creek valley captured the south-oriented flood flow and diverted water more directly to the actively eroding Missouri River valley. Flood waters on north ends of beheaded south-oriented flood channels reversed flow direction to flow north to the newly eroded Weeping Water Creek valley. The flood flow reversal eroded north-oriented Weeping Water Creek tributary valleys and created the Weeping Water Creek-Little Nemaha River drainage divide.

Figure 10a: Detailed map of Goose Creek-Wilson Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

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.