• The purpose of this essay is to use topographic map interpretation methods to explore the Little Chariton River-Missouri River drainage divide area landform origins in Chariton, Randolph, and Howard Counties, Missouri, 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 essays in the Missouri River drainage basin landform origins research project 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 Little Chariton River-Missouri River drainage divide area landform evidence in Chariton, Randolph, and Howard Counties, Missouri will be regarded as evidence supporting the “thick ice sheet that melted fast” paradigm (see menu at top of page for paradigm related essay). This essay is included in the Missouri River drainage basin landform origins research project essay collection.

• Based on topographic map evidence presented in this essay and in other Missouri River drainage basin landform origins research project essays the figure 1 map area was deeply eroded by immense south-oriented glacial melt water floods prior to headward erosion of the valleys, which serve as the present day drainage routes. The ice sheet had been large, probably comparable in size if not larger than the modern-day Antarctic Ice Sheet, and at the time figure 1 valleys were eroded was located north of the figure 1 map area. The figure 1 map area was probably located on the south rim of a deep “hole” in which the ice sheet was located, although topographic evidence of the deep “hole’s” south rim has been almost completely removed by deep melt water flood erosion. The deep “hole” had been formed by crustal warping caused by the ice sheet’s great weight and by deep glacial erosion under the thick ice mass. Melt water floods from this gigantic ice sheet over whelmed whatever drainage systems existed and initially flowed in a south direction across the entire figure 1 map area (and a much larger region) and continued flowing in a south direction until they reached the Gulf of Mexico. Deep valleys then began to erode headward from the Gulf of Mexico, with headward erosion of the deep Mississippi River valley and its tributary valleys systematically capturing almost all flood flow moving to the Gulf of Mexico. Mississippi River tributary valleys eroded headward in sequence from south to north. For example, south of the figure 1 map area, in the state of Arkansas, the deep southeast-oriented Arkansas River valley and its tributary valleys captured the south-oriented flood flow prior to headward erosion of the deep southeast-oriented White River valley and its tributary valleys, which beheaded flood flow routes to the newly eroded Arkansas River valley and Arkansas River tributary valleys. Further north in Missouri, headward erosion of the deep Missouri River valley and its east and northeast oriented Osage River tributary valley (located south of the figure 1 map area) next beheaded flood flow routes to the newly eroded White River valley and its tributary valleys. Flood waters on north ends of beheaded flood flow routes reversed flow direction to erode north-oriented Osage River tributary valleys. Headward erosion of the deep Missouri River valley west of the Jefferson City area (where the east and northeast oriented Osage River joins the Missouri River) next beheaded south-oriented flood flow to the newly eroded Osage River valley.

• South-oriented flood flow to the actively eroding Missouri River valley next eroded deep south-oriented valleys headward from the newly eroded Missouri River valley north wall along south-oriented channels in what had been an immense south-oriented anastomosing channel complex. The south-oriented anastomosing channel complex had been composed of diverging and converging south-oriented flood flow channels eroded into an erosion (deposition?) surface at least as high as the highest northern Missouri elevations today. Flood flow moving south in this anastomosing channel complex was captured as the deep Missouri River valley eroded headward, with the captured flood water diverted to the large south-oriented Mississippi River valley. Headward erosion of these deep south-oriented valleys along south-oriented flood flow channels produced the parallel south-oriented Missouri River tributaries seen in much of north central and northwest Missouri. At the same time new east and southeast oriented tributary valleys began to erode headward from the actively eroding Mississippi River valley north of the newly eroded Missouri River valley and these new east and southeast oriented Mississippi River tributary valleys began to capture south-oriented flood flow routes flowing to the newly eroded Missouri River valley. In time headward erosion of the actively eroding south-oriented Mississippi River valley had captured enough of the south-oriented flood flow that a large southeast-oriented anastomosing channel complex formed in northeast Missouri (and in Iowa to the north). Deep southeast-oriented tributary valleys then eroded headward from the actively eroding Mississippi River valley to produce the parallel southeast-oriented drainage routes seen in northeast Missouri and adjacent Iowa.

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

Figure 2 is a more detailed location map for the Chariton River-Missouri River drainage divide area in Chariton, Randolph, and Howard Counties, Missouri. Figure 2 provides county names and county boundaries are shown. The Missouri River meanders in an east-northeast direction from the figure 2 west edge along the Carroll County south border before turning to flow in a southeast direction along the Chariton County southwest border and then in a south direction along the Howard County west border before turning to flow in an east-southeast direction along the Howard and Boone County southern borders. The Chariton River flows in a south direction from the figure 2 north center edge to the Chariton County northeast corner and then in a south-southwest and south direction to join the Missouri River south of Keytesville. The Little Chariton River is formed just north of Forest Green (in southeast Chariton County) at the confluence of its Middle Fork and East Fork and flows in a south direction to join the Missouri River near Glasgow (located at the Chariton County southern tip). The Middle Fork Little Chariton River flows from the figure 2 north edge in a south direction to Thomas Hill Reservoir in northwest Randolph County and then flows is a south-southwest direction into Chariton County (just east of Salisbury). The East Fork Little Chariton River flows in a south direction in Macon County (just west of Macon) and then in a south-southwest direction across western Randolph County and into southeast Chariton County (just touching the Howard County northernmost point). Silver Creek is a west-northwest oriented tributary originating near Higbee in southern Randolph County and joining the East Fork Little Chariton River near in Chariton County, just west of the Randolph County border. North of Silver Creek is Sweet Spring Creek, which originates near Moberly and which joins the East Fork Little Chariton River near Clifton Hill in western Randolph County. South of Silver Creek is south-southwest oriented Bonne Femme Creek, which originates near Higbee and which joins the Missouri River near New Franklin in southern Howard County. East of Higbee, and originating near Moberly, is south and south-southwest oriented Moniteau Creek, which flows across eastern Randolph County to join the Missouri River near Rocheport in the Howard County southeast corner. Note how headward erosion of the west-oriented Silver Creek and Sweet Spring Creek valleys beheaded south-oriented flood flow to what would have been actively eroding south-oriented Bonne Femme and Moniteau Creek valleys. Also note how headward erosion of the south-southwest Little Chariton River tributaries captured the south-oriented flood flow routes north of the Sweet Spring Creek valley and eroded valleys headward along those south-oriented flood flow routes.

Figure 3: Chariton River-Little Chariton River drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Figure 3 uses a reduced size topographic map to illustrate the Chariton River-Little Chariton River drainage divide area. The labeled Chariton-Howard County line can be seen in the figure 3 south center area and southeast quadrant. Salisbury is the town located just south of the figure 3 north center edge. Keytesville is the unlabeled town straddling the figure 3 north edge near the northeast corner. Armstrong is the town just north of the word PRAIRIE in the figure 3 southeast quadrant. Roanoke is a place-name on the Randolph-Howard County line located directly north of Armstrong (the south to north oriented Chariton-Randolph County line can be seen just west of Roanoke). The south-southeast oriented Missouri River flows across the figure 3 southwest corner. The Chariton River flows in a south-southwest direction from the figure 3 north edge (between Keytesville and Salisbury) to the figure 3 western margin and then flows in a south direction to join the Missouri River. Puzzle Creek is the southwest and west oriented tributary flowing just west of Salisbury to join the Chariton River. Note how Puzzle Creek has northwest-oriented tributaries which are linked by through valleys with southeast-oriented tributaries to the southwest-oriented Middle Fork Little Chariton River, which flows just east of Salisbury to join the southwest-oriented East Fork Little Chariton River, which flows from the figure 3 northeast corner. The Middle and East Forks Little Chariton Rivers join near Oil City, which is a place-name between Shannondale and Forest Green (also place names shown on figure 3) and form the south oriented Little Chariton River, which joins the Missouri River just south of the figure 3 map area. Note how many of the East Little Chariton River tributaries from the east are oriented in northwest directions and join the southwest oriented East Fork Little Chariton River as barbed tributaries. The unlabeled west and northwest oriented tributary in the figure 3 northeast corner area is Sweet Spring Creek. South of Sweet Spring Creek the next major west-oriented tributary is Silver CReek, which has significant north-oriented tributaries in the figure 3 east center area (with headwaters east of Roanoke). South of those north-oriented Silver Creek tributary headwaters are headwaters of south-southeast oriented streams which flow to south-southwest oriented Bonne Femme Creek, which can be seen flowing across the figure 3 southeast corner. South of the figure 3 map area Bonne Femme Creek flows to the Missouri River. Note how south-southeast oriented Bonne Femme Creek tributary valleys are linked by shallow through valleys with north oriented Silver Creek tributary valleys. The north-oriented and barbed tributaries, the shallow north-south oriented through valleys, and the south-southeast-oriented valleys draining to the south-oriented Bonne Femme Creek valley all provide evidence of a former south-oriented flood flow channel which was beheaded and reversed by headward erosion of the southwest-oriented East Fork Little Chariton River valley and its tributary Silver Creek valley. Other somewhat similar, but subtle former flood flow channels can be identified using similar types of evidence, although the evidence is best seen on more detailed topographic maps.

Figure 4: Detailed map of Silver Creek-Bonne Femme 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 Silver Creek-Bonne Femme Creek drainage divide area seen in less detail in figure 3 above. Armstrong is the town located in the figure 4 southwest corner. The north-oriented stream in sections 13 and 12 in the figure 4 north center area is a north-oriented tributary to west-oriented Silver Creek (and is named Bagby Branch north of the figure 4 map area). Bonne Femme Creek flows in a southwest direction across the figure 4 southeast corner. The south-oriented stream flowing from section 19 across section 30 to the figure 4 south edge is a Ganaway Creek tributary, with Ganaway Creek being the northeast and southeast oriented stream directly to west. South of the figure 4 map area south-southeast oriented Ganaway Creek joins Bonne Femme Creek. Note how in the section 19 northwest quadrant a through valley links the south-oriented Bonne Femme Creek (or Ganaway Creek) tributary valley with the north-oriented Silver Creek tributary valley. The map contour interval is ten feet and the through valley floor elevation is between 800 and 810 feet. To the east of the through valley elevations rise to more 840 feet (near Yates near the figure 4 northeast corner there is a spot elevation of 845 feet). East of the figure 4 map elevations are even higher and exceed 880 feet just three miles east of Yates. To the west of the through valley elevations rise to more than 880 feet in section 22 north of Armstrong. Study of the Silver Creek-Bonne Femme Creek drainage divide reveals multiple through valleys, although what appear to be shallow through valleys are actually channels eroded into the floor of a much larger north-south oriented through valley, which extends from the section 22 area to the higher elevations three miles east of Yates. The through valley provides evidence of a major south-oriented flood flow channel which eroded up to 80 feet of material, if not more, from much the figure 4 map area. At the time the through valley was eroded flood waters were probably flowing to what was then the actively eroding Missouri River valley head. Headward erosion of the deep Missouri River valley and its deep Little Chariton River tributary (and its East Fork Little Chariton River valley with its west-oriented Silver Creek tributary valley) then captured the south-oriented flood flow. Flood waters on the north end of the beheaded flood flow channel reversed flow direction to erode the north-oriented Silver Creek tributary valley and to create the Silver Creek-Bonne Femme Creek drainage divide.

Figure 5: Missouri River-Bonne Femme Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Figure 5 illustrates the Missouri River-Bonne Femme Creek drainage divide area located south and slightly east of the figure 3 map area. The south-southwest oriented Missouri River valley is located along the figure 5 west edge with Glasgow being the town on the valley east edge next to the figure 5 north edge. South and west of the figure 5 map area the Missouri River turns to flow in an east direction south of the figure 5 map area. Greggs Creek is west-northwest oriented tributary joining the Missouri River at Glasgow. The Missouri River tributary located immediately south of Greggs Creek is northwest and west oriented Hurricane Creek. Note how other Missouri River tributaries located south of Hurricane Creek are oriented in northwest directions or have significant northwest-oriented segments and/or tributaries. These northwest-oriented tributaries to what in figure 5 is a south-oriented valley provide evidence of reversals of flood flow on north ends of what were once south-oriented flood flow routes. The south-oriented Missouri River valley eroded headward along one such south-oriented flood flow channel and beheaded flood flow routes moving to diverging south-oriented flood flow channels. Fayette is the large town located in the figure 5 southeast quadrant and is located on the west edge of the south-southwest oriented Bonne Femme Creek valley. Adams Fork is the southeast-oriented tributary joining Bonne Femme Creek near Fayette. Note how Bonne Femme Creek tributaries from the west are oriented in southeast directions and in the figure 5 north center area are linked by shallow through valleys with northwest-oriented valleys draining to Missouri River tributaries. For example the southeast-oriented Adams Fork tributary valley in which Fayette Lake is located is linked by shallow through valleys with the northwest-oriented Hurricane Creek headwaters valley. Figure 6 below provides a detailed topographic map  of the Hurricane Creek-Adams Fork drainage divide area to better illustrate the through valleys. The south-oriented streams flowing to the figure 5 south center edge (west of Bonne Femme Creek) are Sulphur Creek headwaters and tributaries. South of the figure 5 map area Sulphur Creek flows in a south direction to join the east-oriented Missouri River (which has turned from flowing in a south direction to flowing in an east direction). Shallow through valleys can also be seen linking headwaters of south-oriented Sulphur Creek valleys with northwest-oriented valleys leading to west-oriented Richland Creek, which flows to the Missouri River just south of the figure 5 west center edge area. The shallow through valleys plus present day valley orientations provide evidence of multiple former diverging and converging flood flow routes.

Figure 6: Detailed map of Hurricane Creek-Adams Fork 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 Hurricane Creek-Adams Fork drainage divide area seen in less detail in figure 5 above. Tick Ridge School will be used a reference point in the following discussion and is located near the figure 6 center. Hurricane Creek originates just south of the figure 6 north center area and flows in a west direction across the figure 6 northwest quadrant and west of the figure 6 map area flows to the south-oriented Missouri River. Note the multiple northwest-oriented Hurricane Creek tributaries in sections 30 and 25. Fayette Lake is located in the valley of southeast-oriented Adams Fork tributary which has headwaters in the section 30 southeast quadrant and the section 29 southwest quadrant near the Tick Ridge School. The stream originating in section 29 north of the Tick Ridge School and flowing in a northeast, east, east-southeast, and south-southeast direction to the figure 6 south edge (near southeast corner) is Adams Fork. South and east of the figure 6 map area Adams Fork joins south-oriented Bonne Femme Creek, which flows to the east-oriented Missouri River. Note how the highest elevations shown on the figure 6 map are just west of Tick Ridge School and are somewhat above 910 feet (the map contour interval is ten feet). Also note in the section 30 southeast quadrant shallow through valleys eroded across the high drainage divide between a northwest-oriented Hurricane Creek tributary valley and the southeast-oriented Adams Fork tributary valley in which Fayette Lake is located. Floors of the shallow through valleys are between 890 and 900 feet in elevation and as already noted the highest observed elevations on either side are at most slightly above 910 feet, meaning the through valleys are not deep. Yet the shallow through valleys are present and provide evidence of southeast-oriented flood flow channels that once moved southeast-oriented flood flow to what was then the actively southeast-oriented Adams Fork tributary valley. Numerous other lower elevation through valleys can be found providing evidence of subsequent flood flow movements as the figure 6 deep valleys were eroded. For example, further north near the Hurricane Creek headwaters in the section 20 southwest quadrant a deeper through valley links the west-oriented Hurricane Creek valley with a southeast-oriented Adams Fork tributary valley. The floor of this through valley has an elevation of between 870 and 880 feet and high points on either side rise to more than 890 feet. The through valleys are not deep, but they cross all figure 6 drainage divides and provide evidence of flood flow routes as large volumes of south-oriented flood flow moving across the figure 6 map region were captured as deep valleys eroded headward into the region.

Figure 7: Missouri River-Moniteau Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Figure 7 uses a reduced size topographic map to illustrate the Missouri River Moniteau Creek drainage divide area south of the figure 5 map area and includes overlap areas with figure 5. The south-oriented Missouri River valley is located along the figure 7 west edge and then turns so as to be oriented in an east-southeast direction along the figure 7 south edge. Fayette is the large town located in the figure 7 northeast quadrant and is located on the west edge of the south-southwest oriented Bonne Femme Creek valley. New Franklin is the smaller town located where the Bonne Femme Creek enters the Missouri River valley (just north of figure 7 south center edge). The labeled south-southwest and south oriented Missouri River tributary located east of Bonne Femme Creek is Salt Creek and the south-oriented Missouri River tributary located near the figure 7 east edge is Moniteau Creek. West of Bonne Femme Creek the south-oriented Missouri River tributary flowing through the word FRANKLIN is Cottonwood Creek. The much longer south-oriented Missouri River tributary west of Cottonwood Creek is Sulphur Creek. Richland Creek is the west oriented tributary joining the Missouri River near the figure 7 northwest corner. Dry Fork is the labeled north-northwest oriented Richland Creek tributary. While difficult to see on figure 7 more detailed topographic maps do show shallow through valleys linking the north-northwest oriented Dry Fork valley with headwaters valleys of Sulphur Creek tributaries and also with west- and southwest-oriented Missouri River tributary valleys. These shallow through valleys provide evidence of one time flood flow channels eroded into a high level erosion (deposition?) surface as least as high if not higher than the highest figure 7 elevations today, probably as the deep Missouri River valley head was eroding headward across the region. Apparently headward erosion of the deep east-southeast oriented Missouri River valley captured a significant south-oriented flood flow channel near the figure 7 west edge and eroded headward along that south-oriented flood flow channel. In doing so south-oriented flood flow was diverted so as to flow first in southwest directions to the actively eroding valley head and then in west directions. Study of drainage divides further east in the figure 7 map area reveals shallow through valleys linking various south-oriented Missouri River tributary valleys, suggesting the major south-oriented valleys eroded headward along diverging and converging flood flow channels in a south-oriented anastomosing channel complex. These shallow through valleys can best be seen along the Bonne Femme Creek-Salt Creek drainage divide, although they can be found along other drainage divides as well. Figure 8 below provides a detailed topographic map of the Bonne Femme Creek-Salt Creek drainage divide area.

Figure 8: Detailed map of Bon Creek-Salt Creek drainage divide area 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 Bonne Femme Creek-Salt Creek drainage divide area seen in less detail in figure 7 above. Mt Zion Church is a reference point used in the following discussion and is located near the figure 8 center. Salt Creek flows in a south-southwest direction from the figure 8 northeast corner to the south edge (just east of center). Bonne Femme Creek meanders in a larger valley in a south direction from the figure 8 north center edge to the south edge (just west of center). Note how Bonne Femme Creek has a number of north, north-northwest, and northwest oriented tributaries from the east. Many Salt Creek tributaries from the west are oriented in southeast, south-southeast, and south directions and are linked by shallow through valleys with Bonne Femme Creek tributaries. The deepest through valley in the figure 8 map area is located near Mt Zion Church in the section 36 northwest quadrant. The map contour interval is 10 feet and the through valley floor elevation is between 670 and 680 feet. High points along the drainage divide both north and south of the through valley rise to more than 740 feet. In other words the through valley is between 60 and 80 feet deep based on present day elevations. Numerous other shallow through valleys cross the drainage divide, although they are not as deep and some are defined by only one of two contour lines on a side. Also of interest are shallow through valleys crossing drainage divides between Bonne Femme Creek and Salt Creek tributaries. For example, in the quarter section south of the quarter section marked as section 28 in the northwest quadrant a north-south oriented through valley links an east-northeast oriented tributary valley to a south-southeast oriented Bonne Femme Creek tributary with a south and east-southeast oriented Bonne Femme Creek tributary valley. The through valley floor elevation is between 690 and 700 feet and elevations immediately to east rise to more than 730 feet while to west they rise to more than 770 feet. The through valley illustrates what was a small-scale diverging and converging flood flow channel beheaded by headward erosion of the deeper south-southeast oriented Bonne Femme Creek tributary valley. Another example is found in the section 6 west half in the southeast quadrant where a shallow through valley links two west-oriented Salt Creek tributary valleys. The through valley floor elevation is between 660 and 670 feet and adjacent elevations on both sides rise to more than 690 feet. These and many other through valleys can be used to at least partially reconstruct what were ever-changing south oriented diverging and converging flood channels eroded by flood waters as deep valley eroded headward into the figure 8 map area.

Figure 9: East Fork Little Chariton River-Moniteau Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Figure 9 uses a reduced size topographic map to illustrate the East Fork Little Chariton River-Moniteau Creek drainage divide area located north of the figure 7 map area and north and east of the figure 3 map area (and includes overlap areas with figure 3). Moberly is the large town located in the figure 9 northeast quadrant. Roanoke is the place-name located on the county line in the figure 9 southwest quadrant (and was seen in figure 3). Higbee is the small town located near the south edge in the figure 9 southeast quadrant. Renick is a small town north of the figure 9 southeast corner. Clifton Hill is a town in the figure 9 northwest quadrant and Huntsville is located between Clifton Hill and Moberly. North-northeast oriented drainage east of Moberly flows to an east-oriented Mississippi River tributary, so Moberly is located on the Missouri River-Mississippi River drainage divide. The East Fork Little Chariton River flows from the figure 9 north center edge in a south and then southwest direction to the figure 9 west edge (just south of center). Sugar Creek is the west-oriented tributary flowing from Sugar Creek Lake (north of Moberly along north edge) to join the East Fork Little Chariton River north of Huntsville. Sinking Creek is the southwest East Fork tributary flowing between the East Fork and Sugar Creek. The west-oriented tributary originating on the west side of Moberly and flowing south of the highway to join the East Fork south of Clifton Hill is Sweet Spring Creek. Note how Sweet Spring Creek has northwest and southwest oriented valley segments and also has numerous north oriented tributaries from the south. The north-oriented tributary valleys were eroded by reversals of flood flow on north ends of beheaded south-oriented flood flow routes. South of Sweet Spring Creek and flowing in a northwest, west-southwest, and west-northwest direction from just west of Higbee is Silver Creek, which also has north-oriented tributaries from the south. Just south of the northwest-oriented Silver Creek headwaters along the figure 9 south center edge are headwaters of south-oriented Bonne Femme Creek. Headward erosion of the East Fork Little Chariton River valley and its tributary Silver Creek valley beheaded south-oriented flood flow moving to what was then the actively eroding Bonne Femme Creek valley. Flood waters on north ends of the beheaded flood flow routes reversed flow direction to erode the north-oriented Silver Creek headwaters and tributary valleys. The south-oriented stream flowing to the figure 9 south edge just east of Higbee is the headwaters of south oriented Moniteau Creek. Note how the south-oriented Moniteau Creek valley is aligned with north- and northwest-oriented Sweet Spring Creek tributary valleys. The map contour interval is ten meters and relief away from the stream valleys is very low, however evidence for some shallow through valleys can be seen. Figure 10 below provides a detailed topographic map of the Sweet Spring Creek-Moniteau Creek drainage divide area to better illustrate relationships in that region.

Figure 10: Detailed map of Sweet Spring Creek-Moniteau 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 Sweet Spring Creek-Moniteau Creek drainage divide area seen in less detail in the figure 9 map area. Renick is the town located in the figure 10 southeast corner. Northeast and north oriented drainage in figure 10 eastern third and flowing to the figure 10 east edge and northeast corner flows to an east-oriented Mississippi River tributary. North and northwest oriented streams in the figure 10 western two-thirds and flowing to the figure 10 north and west edges are Sweet Spring Creek tributaries, with Sweet Spring Creek flowing to the southwest-oriented East Fork Little Chariton River, which eventually flows to the south oriented Missouri River west of figure 10. The south oriented stream flowing to the figure 10 south center edge is Moniteau Creek, which flows to the Missouri River south of the figure 10 map area. Note how near the section 27 center a shallow through valley links a north-oriented Sweet Spring Creek tributary valley with the south-oriented Moniteau Creek valley. The map contour interval is ten feet and the through valley floor elevation is between 860 and 870 feet. At first glance the through valley appears to be defined by one contour line on each side. However, by proceeding further in each direction elevations rise to more than 880 feet. While not deep the through valley provides evidence of a south oriented flood flow channel to what was probably the actively eroding Moniteau Creek valley, which was eroding headward from the newly eroded Missouri River valley. Headward erosion of the west oriented Sweet Spring Creek valley from the East Fork Little Chariton River valley then beheaded the south-oriented flood flow. Flood waters on the north end of the beheaded flood flow channel reversed flow direction to erode the north-oriented Sweet Spring Creek tributary valley. At the same time as the Sweet Spring Creek valley was eroding headward into the region and the south- and southwest-oriented East Fork Little Chariton River valley was eroding headward further to the north an east-oriented Mississippi River tributary valley (Elk Fork Salt Creek) and its tributary valleys (Coon Creek) were also eroding headward into the region to capture south oriented flood flow routes to the newly eroded Missouri River valley. Flood waters on north ends of beheaded flood flow routes also reversed flow direction to erode north oriented tributary valleys. The Missouri River-Mississippi River drainage divide in figures 9 and 10 was created as headward erosion of these two opposing valley systems and their tributary valleys ended when all south oriented flood flow channels had been captured.

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.