Abstract:

Topographic map interpretation methods are used to interpret East Fork Grand River-Thompson River drainage divide area landform origins in Worth, Gentry, and Harrison Counties, Missouri. The East Fork Grand River-Thompson River drainage divide area consists of multiple drainage divides between several narrow and elongate south-oriented Grand River tributary drainage basins. The East Fork Grand River and some of its tributaries originate in Iowa and flow in southwest and south directions into Worth and Gentry Counties, which are located in Missouri directly south of the Iowa border. In Gentry County (south of Worth County) the south-oriented East Fork Grand River joins the southeast-oriented Grand River, which then flows to the join the Missouri River. Further east the Thompson River and some of its tributaries also originate in southern Iowa and flow in south-southeast and south directions into and across Harrison County, Missouri, which is directly east of Worth and Gentry Counties. South of Harrison County the Thompson River also joins the Grand River. The multiple converging south-oriented Grand River tributary valleys were eroded headward along what were once diverging and converging south-oriented channels in an immense flood formed anastomosing channel complex, some of which was captured by headward erosion of the deep southeast-oriented Grand River valley. Headward erosion of deep south-oriented valleys along flood flow channels then beheaded north ends of diverging south-oriented channels. Flood waters on north ends of beheaded flood flow channels reversed flow direction to erode north-oriented tributary valleys. Today these north-oriented barbed tributary valleys are linked by shallow through valleys with south-oriented valleys. Valley orientations and alignments, barbed tributaries, elbows of capture, and shallow through valleys all support this flood origin interpretation.

Preface

Introduction

• The purpose of this essay is to use topographic map interpretation methods to explore the East Fork Grand River-Thompson River drainage divide area landform origins in Worth, Gentry, and Harrison 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 East Fork Grand River-Thompson River drainage divide area landform evidence in Worth, Gentry, and Harrison 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.

East Fork Grand River-Thompson River drainage divide area location map

Figure 1: East Fork Grand River-Thompson River drainage divide area location map (select and click on maps to enlarge). National Geographic Society map digitally presented using National Geographic Society TOPO software.

 

• Figure 1 provides a location map for the East Fork Grand River-Thompson River drainage divide area in Worth, Gentry, and Harrison Counties Missouri and illustrates regions in northwest Missouri, southwest Iowa, southeast Nebraska, and northeast Kansas. The Missouri River flows in a south-southeast direction from Omaha, Nebraska to Kansas City, Missouri and then turns to flow in an east-northeast direction to Brunswick, Missouri. At Brunswick the Missouri River turns to flow in a southeast and south direction to the figure 1 south edge. South of the figure 1 map area the Missouri River flows in more of an east direction to join the south-oriented Mississippi River east of the figure 1 map area. The Grand River originates near Afton, Iowa (south of the figure 1 north center edge) and flows in a south direction through Diagonal, Iowa into northern Missouri before turning to join an unlabeled south-oriented stream near Albany, Missouri. The unlabeled south-oriented Grand River tributary near Albany is the East Fork Grand River. From the Albany area the Gand River flows in a southeast direction to a point north of Brunswick and then turns to flow in a south direction to join the Missouri River near Brunswick. The Thompson River originates north of the figure 1 map area and flows in a south-southeast direction to Grand River and Davis City, Iowa (east of the Grand River) before entering northern Missouri. Once in Missouri the Thompson River flows in a south-southeast and south direction through Trenton to join the southeast-oriented Grand River near Utica, Missouri. The East Fork Grand River-Thompson River drainage divide area in Worth, Gentry, and Harrison Counties, Missouri is located directly south of the Iowa-Missouri state line and includes the towns of Albany, New Hampton, and Bethany and is bounded on the west by the East Fork Grand River, on the east by the Thompson River, on the north by the state line, and on the south by the East Fork Grand River south end. Essays describing adjacent drainage divide areas include the Chariton River-Grand River drainage divide area landform origins in Lucas, Decatur, and Wayne Counties, Iowa essay, the Platte River-Thompson River drainage divide area landform origins in Adair, Union, Ringgold, and Decatur Counties, Iowa essay, the One Hundred and Two River-East Fork Grand River drainage divide area in Nodaway, Gentry, and Worth Counties, Missouri essay, and the Grand River-Shoal Creek drainage divide area in Daviess, Caldwell, and Livingston Counties, Missouri essay. Essays can be found under MO Grand River on the sidebar category list.

• Based on topographic map evidence illustrated in this essay and on evidence presented in other Missouri River drainage basin landform origins research project essays the East Fork Grand River-Thompson River drainage divide area and in fact the entire figure 1 map region (plus a much larger region) was eroded by massive south oriented glacial melt water floods. Flood waters were derived from a rapidly melting North American ice sheet, which at the time the figure 1 map area drainage systems were established was located north of the figure 1 map area. The ice sheet at one time had been as large if not larger than the present day Antarctic Ice Sheet and had been located in a deep “hole”. The deep “hole” had been created by deep glacial erosion and also by crustal warping caused by the ice sheet’s tremendous weight. The figure 1 map area was probably located along the deep “hole’s” southern rim, although today no evidence of the southern remains. The southern rim area was deeply eroded by immense south-oriented melt water floods flowing from the rapidly melting ice sheet to the Gulf of Mexico. Modern river systems evolved as deep valleys eroded headward from the Gulf of Mexico to capture the south-oriented flood flow. The most significant of these deep valleys was the south-oriented Mississippi River valley, which by eroding deep tributary valleys headward in both directions was able to capture most of the south-oriented melt water flood flow.

• Of concern in this Missouri River drainage basin landform origins research project are deep tributary valleys which eroded headward in a west direction from the actively eroding south-oriented Mississippi River valley. These tributary valleys and their tributary valleys were eroded in sequence from south to north and also from east to west. For example, in the state of Arkansas, south of the figure 1 map area, the southeast-oriented Arkansas River valley and its tributary valleys eroded headward prior to headward erosion of the deep southeast-oriented White River valley and its tributary valleys, which captured south-oriented flood flow that had been moving to the newly eroded Arkansas River valley and its tributary valleys. Just south of the figure 1 map area headward erosion of the Missouri River valley and its tributary east and northeast oriented Osage River valley next beheaded south-oriented flood flow to the newly eroded White River valley and its actively eroding south-oriented tributary valleys. Next headward erosion of the Missouri River valley into the figure 1 map area captured the south-oriented flood flow, beheading flood flow routes to the newly eroded Osage River valley. South-oriented tributary valleys then eroded headward from the newly eroded Missouri River valley. One of these south-oriented valleys, the southeast-oriented Grand River valley segment, eroded across multiple south-oriented flood flow routes while the south-oriented Thompson River valley eroded headward along a major south-oriented flood flow route. The multiple south-oriented flood flow channels captured by headward erosion of the southeast-oriented Grand River valley segment suggest flood waters were flowing in what was at that time an immense south-oriented anastomosing channel complex.

Detailed location map for East Fork Grand River-Thompson River drainage divide area

Figure 2: Detailed location map for East Fork Grand River-Thompson River drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

 

• Figure 2 provides a more detailed location map for the East Fork Grand River-Thompson River drainage divide area in Worth, Gentry, and Harrison Counties, Missouri. County names and boundaries are shown. The west to east oriented Iowa-Missouri state line is located north of Worth, Harrison, and Mercer Counties, which are located in Missouri, and south of Taylor, Ringgold, Decatur, and Wayne Counties, which are located in Iowa. The Grand River flows in a south and southwest direction from the figure 2 north edge to the Ringgold County southwest corner and into northwest Worth County where it turns to flow in a south direction into northwest Gentry County. Once in Gentry County the Grand River flows in a south-southeast and southeast direction to the Gentry County southeast corner and then across Daviess County. The Middle Fork Grand River originates near Mount Ayr in Ringgold County and flows in a south-southwest direction to near Grant City in Worth County before turning to flow in a south direction to join the Grand River in central Gentry County. The East Fork Grand River originates a short distance north of the figure 2 map area and flows in a south and south-southwest direction in eastern Ringgold County to the Worth County northeast corner and then flows in a south-southwest and south direction to join the Grand River near Albany in Gentry County. The Thompson River originates north of the figure 2 map area and flows in a south-southeast direction across western Decatur County to the Harrison County northeast corner and then flows in a south direction along the Harrison County east border to the Grundy County northwest corner. Once in Gundy County the Thompson River flows in a south-southeast and south direction to the figure 2 south edge and joins the southeast oriented Grand River south of the figure 2 map area. Between the south-oriented East Fork Grand River and the south-oriented Thompson River there are a number of other south-oriented streams. Proceeding from west to east these streams include several south- and southwest-oriented East Fork Grand River tributaries, with Lotts Creek, Little Muddy Creek, Big Muddy Creek, and Panther Creek being the figure 2 labeled tributaries. East of the East Fork Grand River drainage basin is the south-oriented Big Creek drainage basin in central Harrison County with several closely spaced and roughly parallel tributary streams, including Little Creek, West Fork Big Creek, Shain Creek, East Fork Big Creek, and Polecat Creek. East of the Big Creek drainage basin is the south-oriented Thompson River drainage basin with several southeast and east-oriented tributaries, including Brush Creek, Trail Creek, and Fox Creek. Note how all drainage basins in the study region are elongate and narrow and oriented in south directions. These elongate and narrow south-oriented drainage basins originated as deep valleys eroded headward along channels in what was at that time an immense south-oriented anastomosing channel complex. Evidence supporting this anastomosing channel complex origin hypothesis is illustrated in the sample topographic maps shown below.

East Fork Grand River-West Fork Big Creek drainage divide area

Figure 3: East Fork Grand River-West Fork Big Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

 

• Figure 3 illustrates the East Fork Grand River-West Fork Big Creek drainage divide area along the Iowa-Missouri state border. The labeled Iowa-Missouri state line is located near the figure 3 north edge. Hatfield is the small town located north of the figure 3 center. Allendale is the small town located near the west edge (south half). The East Fork Grand River flows in a southwest direction across the figure 3 northwest corner. Lotts Creek flows in a south-southwest, west-southwest, and southwest direction from the figure 3 north center edge to the figure 3 west edge and is an East Fork Grand River tributary. Note how Lotts Creek has several north-oriented barbed tributaries. Long Branch north of Hatfield is the longest of the north-oriented tributaries. South of the north-oriented Long Branch headwaters are headwaters of the south-oriented East Fork Big Muddy Creek. Note shallow through valleys linking the north-oriented Long Branch valley with the south-oriented East Fork Big Muddy Creek valley. Figure 4 below provides a detailed topographic map of the Long Branch-East Fork Big Muddy Creek drainage divide area to better illustrate the through valleys. South of Hatfield is south-southeast oriented West Fork Big Muddy Creek, which joins the East Fork Big Muddy Creek near the figure 3 south center edge to form south-oriented Big Muddy Creek, which flows to the figure 3 south center edge and is an East Fork Grand River tributary. Note how the south-oriented West Fork Big Muddy Creek valley is linked by shallow through valleys with unnamed north-oriented Lotts Creek tributary valleys. The valley orientations, barbed tributaries, and shallow through valleys provide evidence of what were once south-oriented flood flow channels beheaded by headward erosion of the deep southwest-oriented Lotts Creek valley. Flood waters on north ends of the beheaded flood flow channels reversed flow direction to erode the north-oriented (and barbed) Lotts Creek tributary valleys. Also in figure 3 is the south-southwest and south-southeast oriented West Fork Big Creek, which flows from the figure 3 northeast corner to the southeast corner. Wolf Creek is the south-southeast oriented tributary joining the West Fork Big Creek near the very small town of Pawnee. Shain Creek is the south-oriented West Fork Big Creek tributary seen in the figure 3 east center edge area and joins the West Fork Big Creek south of the figure 3 map area. A close look at drainage divides between West Fork Big Creek tributaries reveals additional shallow through valleys providing evidence of additional south-oriented flood flow channels, which were eroded into a surface at least as high as the highest figure 3 elevations today. The flood flow channels were beheaded as south-oriented deep valleys and their deep tributary valleys eroded headward into the region in sequence from south to north

Detailed map of Long Branch-East Fork Big Muddy Creek drainage divide area

Figure 4: Detailed map of Long Branch-East Fork Big Muddy 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 Long Branch-East Fork Big Muddy Creek drainage divide area seen in less detail in figure 3 above. Hatfield is the small town located slightly west of the figure 4 south center area. Lotts Creek flows in a south-southwest and west direction in the figure 4 northwest quadrant. Long Branch is the north-northwest and north oriented Lotts Creek tributary flowing to the figure 4 north edge (directly north from Hatfield). Note other north- and northwest oriented Lotts Creek tributaries originating north and west of Hatfield. South-oriented East Fork Big Muddy Creek originates in the south half of section 1 and flows in a south direction across section 12 and section 13 to reach the figure 4 south edge (slightly east of center). Note the southeast-oriented tributary flowing from the section 11 northeast quadrant to join the East Fork Big Muddy Creek near the section 12 south edge and another southeast-oriented tributary flowing from the section 11 southwest quadrant to join the East Fork Big Muddy Creek south of the figure 4 map area. The south-oriented East Fork Big Muddy Creek valley and its southeast-oriented tributary valleys are linked by shallow through valleys with the north- and northwest oriented Lotts Creek tributary valleys. One of the deepest through valley shown is in the section 11 southwest quadrant and has a valley floor elevation of between 1140 and 1150 feet (the map contour interval is ten feet). Elevations in Hatfield rise to more than 1170 feet and elevations in section 1 to the northeast rise to more than 1180 feet. In other words the through valley is between 20 and 40 feet deep. Two other through valleys with similar depths are located in the south half of section 2. The eastern through valley links the north-oriented Long Branch valley with a southeast-oriented East Fork Big Muddy Creek tributary valley while the western through valley links a northwest, southwest, and west oriented Lotts Creek tributary valley with the same southeast-oriented East Fork Big Muddy Creek tributary valley. The linkage with the northwest, southwest, and west oriented Lotts Creek tributary valley may at first appear inconsistent with the south-oriented flood flow channel interpretation. But study the drainage divide between that tributary and Lotts Creek and note the through valley crossing that drainage divide which is aligned with the northwest-oriented tributary valley segment. In other words, initially there was a south-southeast oriented flood flow channel moving flood water to the actively eroding south-oriented East Fork Big Creek valley. Headward erosion of the deep Lotts Creek valley and its southwest and west oriented tributary valley first captured the flood flow, while headward erosion of the Lotts Creek valley next beheaded the flood flow channel further to the northwest.

West Fork Big Creek-Thompson River drainage divide area

Figure 5: West Fork Big Creek-Thompson River drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.

 

• Figure 5 illustrates the West Fork Big Creek-Thompson River drainage divide area located east of the figure 3 map area. The west to east oriented county line located near the figure 5 north edge is also the Iowa-Missouri state line. Blytheville is the town near the figure 5 south center and Eagleville is the town west of Blytheville in the figure 5 southwest quadrant. The West Fork Big Creek flows in a south-southwest and south-southeast direction from the figure 5 north edge (near northwest corner) to the figure 5 south edge (near southwest corner). Wolf Creek is the south-southeast oriented tributary joining the West Fork Big Creek at Pawnee near the figure 5 west center edge. The south-oriented stream flowing from the figure 5 north edge to the south edge just east of the West Fork Big Creek is Shain Creek. South of the figure 5 map area Shawn Creek joins the West Fork Big Creek. The East Fork Big Creek flows from the figure 5 north center edge in a south direction between Eagleville and Blytheville to the figure 5 south center edge. Note how the East Fork Big Creek has several south- and southeast-oriented tributaries, including Zadie Creek (in the figure 5 north center area), Bracken Branch (joining the East Fork Big Creek west of Blytheville), and Barber Branch (located north of Eagleville). The Shain Creek-East Fork Big Creek drainage divide is an asymmetric drainage divide where southeast-oriented East Fork Big Creek tributaries are much better developed than the much shorter Shain Creek tributaries. Figure 6 below provides a detailed topographic map of the Shain Creek-Bracken Branch drainage divide area to better illustrate relationships in that region. The large south-oriented valley located along the figure 5 east edge is the Thompson River valley and the south-oriented Thompson River channel meanders, with some straight segments, from the figure 5 northeast corner to the southeast corner. Note how the East Fork Big Creek-Thompson River drainage divide is another asymmetric drainage divide with southeast-oriented Thompson River tributaries beginning almost on the edge of the East Fork Big Creek valley. These southeast-oriented Thompson River tributaries include Indian Creek and its southeast-oriented Stone Quarry Creek tributary, Donaby Creek, and Brush Creek. Unfortunately the contour interval for much of the figure 5 northeast region is 20 meters and through valleys crossing the drainage divide are not deep enough to see, although shallow through valleys can be seen on more detailed topographic maps. For example a shallow through valley north of Blytheville links the southeast-oriented Brush Creek headwaters valley with a short northwest-oriented East Fork Big Creek tributary valley. The asymmetric drainage divides suggest headward erosion of the deep East Fork Big Creek valley beheaded southeast-oriented flood flow routes to actively eroding Thompson River tributary valleys and headward erosion of the Shain Creek valley beheaded flood flow to southeast-oriented East Fork Big Creek tributary valleys.

Detailed map of Shain Creek-Bracken Branch drainage divide area

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

 

• Figure 6 provides a detailed map of the Shain Creek-Bracken Branch drainage divide area seen in less detail in figure 5 above. Shain Creek flows in a south direction from the figure 6 north edge into and across section 7 and in section 18 turns to flow in a southwest direction across the section 13 southeast corner and then in a south direction across section 24 to the figure 6 south edge (west half). Note short north and northwest oriented Shain Creek tributaries especially in sections 18 and 19. The Bracken Branch flows in a southeast direction from the south half of section 17 across section 20 to the figure 6 south edge (east half) and as seen in figure 5 above is a much longer stream than the short Shain Creek tributaries. South-oriented headwaters of the Barber Branch can also be seen near the figure 6 south center edge. Note how the southeast-oriented Bracken Branch valley is linked by a shallow through valley along the section 17-18 border with a short northwest-oriented Shain Creek tributary valley. The map contour interval is ten feet and the through valley floor elevation is between 1090 and 1100 feet. Elevations on either side of the through valley rise to more than 1120 feet suggesting the through valley is between 20 and 40 feet deep. The through valley provides evidence of a southeast-oriented flood flow channel to what was once an actively eroding southeast-oriented Bracken Branch valley, which had eroded headward from the newly eroded East Fork Big Creek valley prior to headward erosion of the deep Shain Creek valley. Headward erosion of the deep south-oriented Shain Creek valley beheaded the southeast-oriented flood flow channel and flood waters on the northwest end of the beheaded flood flow channel reversed flow direction to erode the short northwest-oriented Shain Creek tributary valley. Other shallow through valleys can also be seen in the figure 6 map area although they are even shallower suggesting the flood flow may have moved as sheets of southeast-oriented flood water.

East Fork Grand River-Big Creek drainage divide area

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

 

• Figure 7 illustrates the East Fork Grand River-Big Creek drainage divide area south of the figure 3 map area. Albany is the town located near the figure 7 southwest corner and Bethany is the town near the southeast corner. New Hampton is midway between Albany and Bethany. Martinsville is the smaller town slightly to the northeast of the figure 7 center. Denver is the small town located in the figure 7 northwest corner and Brooklyn is the small town near the northeast corner. The south oriented East Fork Grand River valley is located along the figure 7 west edge. Big Muddy Creek is the southwest and west oriented tributary flowing from the figure 7 north center edge to join the East Fork Grand River south of Denver. Long Branch (different from the figures 3 and  4 Long Branch) is the southwest-oriented tributary joining Big Muddy Creek near the figure 7 north center edge. Panther Creek is the south and southwest-oriented tributary joining the East Fork Grand River just south of the figure 7 west center edge area. Note how the south-oriented Panther Creek headwaters valley is linked by a well-defined through valley with the southwest-oriented Long Branch valley.

• The through valley is defined by two 10-meter contour lines on each side and provides evidence of a south-oriented flood flow channel beheaded by headward erosion of the deep Long Branch valley. Weldon Branch is the southwest-oriented tributary joining the East Fork Grand River north of Albany and Town Branch is the southwest-oriented tributary joining the East Fork Grand River near Albany. The south-southeast oriented stream in the figure 7 east half flowing from the figure 7 north edge to Bethany is Little Creek (Little Creek has a south-southeast oriented West Fork and a south-southwest oriented main stream seen near the north edge). Near Bethany in the figure 7 southeast corner area Little Creek joins south-oriented West Fork Big Creek and the south-southwest oriented East Fork Big Creek to form south-oriented Big Creek, which flows to the figure 7 south edge (just west of Bethany). The West Fork Big Creek flows in a south direction from the figure 7 north edge (north of Brooklyn) to join Little Creek near Bethany and is joined by south-oriented Shain Creek near Brooklyn. The south-oriented stream flowing through New Hampton to the figure 7 south center edge is Sampson Creek, which south of the figure 7 map area flows directly to the southeast-oriented Grand River. Jacks Branch is a south-oriented stream originating between Albany and New Hampton and joining Sampson Creek south of the figure 7 map area. Between New Hampton and Bethany is south-oriented White Oak Creek, which south of the figure 7 map area joins Sampson Creek before Sampson Creek flows to the Grand River. Note how headward erosion of the southwest-oriented Panther Creek valley beheaded south-oriented flow to the south-oriented Sampson Creek valley (and also to the south-oriented White Oak Creek valley near Martinsville). Also note how headward erosion of Little Creek tributary valleys beheaded south-oriented flood flow to some of the south-oriented White Oak Creek headwaters valleys. The pattern of closely spaced, narrow, and elongate converging drainage basins originated as a south-oriented complex of diverging and converging (or anastomosing) flood flow channels.

Detailed map of Weldon Branch-Jacks Branch drainage divide area

Figure 8: Detailed map of Weldon Branch-Jacks Branch 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 Weldon Branch-Jacks Branch drainage divide area seen in less detail in figure 7 above. Weldon Branch is the southwest and west oriented stream flowing from the figure 8 north center edge to the west edge (south of the northwest corner). Note short north oriented tributaries from the south. Town Branch originates in the section 1 southwest quadrant and flows in a southwest, west, and southwest direction to the figure 8 west edge (near southwest corner). Note short north, northwest, and west oriented tributaries from the south and south-southeast and south oriented tributaries from the north (in addition to some southwest-oriented tributaries). Weldon Branch and Town Branch flow to the south-oriented East Fork Grand River located west of the figure 8 map area. Jacks Branch is the south-oriented stream flowing to the figure 8 south center edge. South of the figure 8 map area Jacks Branch flows to south-oriented Sampson Creek, which flows directly to the southeast-oriented Grand River. Note how in section 14 the south-oriented Jacks Branch valley is linked by a through valley with a north-oriented Town Branch tributary valley. The through valley floor elevation is between 316 and 320 meters (the map contour interval is 4 meters). Elevations on either side of the through valley rise to more than 324 meters, meaning the through valley is between 4 and 12 meters deep. Also note how opposite the north-oriented Town Branch tributary valley is a southwest-oriented Town Branch tributary valley, which is linked by a north-south oriented through valley in section 11 with a north-oriented Weldon Branch tributary valley. The floor of the section 11 through valley also has an elevation of between 316 and 320 meters, although elevations west of the through valley do not reach 324 meters. The two through valleys are on the Jacks Branch alignment and provide evidence of a south-oriented flood flow channel to what was once the actively eroding south-oriented Jacks Branch valley. The south-oriented flood flow channel was first captured and beheaded by headward erosion of the deep Town Branch valley. Flood waters on the north end of the beheaded flood flow channel reversed flow direction to erode the north-oriented Town Branch tributary valley. Next headward erosion of the deep Weldon Branch valley beheaded the south-oriented flood flow channel and again flood waters on the north end of the beheaded flood flow route reversed flow direction to erode a north-oriented (and barbed) tributary valley.

Big Creek-Thompson River drainage divide area

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

 

• Figure 9 illustrates the Big Creek-Thompson River drainage divide area west of the figure 7 map area and south of the figure 5 map area and includes overlap areas with figure 7. Bethany is the larger town located in the figure 9 northwest quadrant. As described in the figure 7 discussion south oriented Big Creek is formed just west of Bethany at the confluence of south oriented Little Creek and the south-southwest oriented West and East Forks Big Creek. Polecat Creek is a south-southwest oriented Big Creek tributary flowing from the figure 9 north center edge area to join Big Creek near the word CYPRESS in the southwest corner area. The south and south-southeast oriented valley along the figure 9 east edge is the Thompson River valley with the Thompson River flowing in what appears a recently straightened channel. The Thompson River has both southeast and northeast oriented tributaries from the west. Queens Branch is a northeast-oriented tributary near the north edge and is joined near the north edge by southeast-oriented Trail Creek. Sugar Creek is the south- and southeast-oriented stream (with a jog to the northeast in the figure 9 southeast quadrant) flowing from the figure 9 north center area to the south edge (just west of southeast corner). Sugar Creek joins the Thompson River south and east of the figure 9 map area. Fox Creek is the south and south-southeast oriented tributary joining southeast-oriented Sugar at the north end of its jog to the northeast. Note how Fox Creek headwaters are located south of the northeast-oriented Queens Branch headwaters and how the northeast-oriented Queens Branch valley is linked to the south-oriented Fox Creek valley by shallow through valleys. The map contour interval is ten meters and the through valleys are defined one contour line on each side. Figure 10 below provides a detailed topographic map of the Queens Branch-Fox Creek drainage divide area to better illustrate the through valleys. East of Fox Creek is south-southeast and east-oriented Cat Creek, which flows through the Wayne Helton Memorial State Wildlife Area. Note how the south-oriented Cat Creek valley is linked by shallow through valleys to north-oriented Queens Branch tributary valleys. Valley orientations and alignments, barbed tributaries, and shallow through valleys all provide evidence of multiple south-oriented flood flow routes beheaded by headward erosion of the deep Queens Branch valley.

Detailed map of Queens Branch-Fox Creek drainage divide area

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

 

• Figure 10 provides a detailed map of the Queens Branch-Fox Creek drainage divide area seen in less detail in figure 9 above. The south tormented Thompson River valley is located along the figure 10 east margin. Queens Branch flows in a north direction along the figure 10 west center edge and then turns to flow in a northeast direction to the figure 10 north center edge. North of the figure 10 map area Queens Branch joins east oriented Trail Creek, which flows to the Thompson River. Note north-oriented Queens Branch and Trail Creek tributaries and also northeast and north-northeast oriented tributaries draining to the south-oriented Thompson River valley. Fox Creek originates in section 7 (in the figure 10 southwest quadrant) and flows in a south-southeast direction to the figure 10 south edge (west half). Note how the south-oriented Fox Creek valley is linked by a broad shallow through valley with northwest-oriented and north-northeast oriented Queens Branch tributaries. The unnamed south-oriented stream originating in section 8 and flowing to the figure 10 south edge (west half) east of Fox Creek is a Fox Creek tributary. Note how in the section 8 north half that south-oriented Fox Creek tributary is linked by a shallow through valley with a north-oriented Queens Branch tributary valley. The south-oriented stream still further east and flowing to the Wayne Helton Memorial  State Wildlife Area near the figure 10 south edge (just east of center) is Cat Creek. Note how the south-oriented Cat Creek valley is linked by shallow through valleys to a north -oriented Trail Creek tributary valley and a north-northeast oriented valley draining to the south-oriented Thompson River valley. All through valleys mentioned here are defined by one or two 4-meter contour lines on each side. While shallow the through valleys do exist and they provide evidence of former south oriented flood flow routes to what were once actively eroding south-oriented Cat Creek and Fox Creek valleys. At that time the deep south-oriented Thompson River valley was eroding headward into the region and the south-oriented Cat and Fox Creek valleys had eroded headward from that newly eroded Thompson River valley. Headward erosion of the deep Thompson River valley then beheaded a south-southwest oriented flood flow channel to the actively eroding Cat Creek valley and next headward erosion of deep east-oriented Trail Creek valley and northeast-oriented Queens Branch valley from the actively eroding Thompson River valley beheaded remaining flood flow channels to the Cat Creek valley and all flood flow channels to the actively eroding Fox Creek valley and its tributary valley.

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.