Abstract:

Introduction:

• The purpose of this essay is to use topographic map interpretation methods to explore northeast Wyoming Inyan Kara Creek-Stockade Beaver Creek drainage divide area landform origins. 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 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 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 similar essays is a thick North American ice sheet, comparable in thickness to the present day Antarctic ice sheet, occupied approximately the North American region usually recognized to have been glaciated and through its weight and erosive actions created a “deep” North American “hole”, 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 Inyan Kara Creek-Stockade Beaver Creek drainage divide area landform evidence will be regarded as evidence supporting the “thick ice sheet that melted fast” paradigm.

Inyan Kara Creek-Stockade Beaver Creek drainage divide area general location map

Figure 1: Inyan Kara Creek-Stockade Beaver Creek drainage divide area general 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 Inyan Kara Creek-Stockade Beaver Creek drainage divide area. The map illustrates an area in western South Dakota (Rapid City is located in South Dakota) and in northeastern Wyoming (Devils Tower is in Wyoming). Inyan Kara Creek is the unlabeled stream originating south of Sundance, Wyoming and flowing northwest to join the northeast-oriented Belle Fourche River near Carlile, Wyoming. Stockade Beaver Creek is the unlabeled stream originating near Four Corners, Wyoming and flowing south along the Wyoming side of the Wyoming-South Dakota border to join southeast-oriented Beaver Creek and then the southeast-oriented Cheyenne River. The Inyan Kara Creek-Stockade Beaver Creek drainage divide area illustrated and discussed here is generally south of Inyan Kara Creek, north and east of Upton, Wyoming, north of highway 16, and west of the state line, although figures 9 and 10 illustrate Inyan Kara Creek tributaries north of Inyan Kara Creek. The Redwater River-Spearfish Creek drainage divide area essay discusses the region north of the Inyan Kara Creek-Stockade Beaver Creek drainage divide area (found under Belle Fourche River on sidebar category list). Figure 1 shows several streams originating in the Black Hills and flowing southeast to join the northeast-oriented Cheyenne River east of the Black Hills. The northernmost on figure 1 is Elk Creek. Rapid Creek is the unlabeled southeast-oriented stream south of Boxelder Creek and flows through Rapid City. Spring Creek is the unlabeled stream immediately south of Rapid Creek and flows through Hill City. Battle Creek is the unlabeled stream south of Spring Creek and flows through Keystone and Hermosa. French Creek flows through Fairburn.

• Beaver Creek is not shown, but originates near Custer and flows south to Pringle before turning southeast to flow to Buffalo Gap and the Cheyenne River. Fall River is also not shown, but flows from Hot Springs southeast to join the Cheyenne River. Red Canyon Creek flows has drainage divides with French Creek and Beaver Creek, which are discussed in the Red Canyon Creek-Beaver Creek drainage divide essay (found under Cheyenne River). Stockade Beaver Creek originates further north than Red Canyon Creek and has drainage divides with Rapid Creek and Spring Creek, which are discussed in the Spring Creek-Battle Creek drainage divide area and Rapid Creek-Spring Creek drainage divide area essays (found under Cheyenne River). Black Hills drainage system evolution is closely related to the evolution of the southeast and northeast oriented Cheyenne River valley and its tributary northeast and southeast-oriented Belle Fourche River valley.

• This essay interprets Inyan Kara Creek-Stockade Beaver Creek drainage divide area landform origins in the context of an immense southeast oriented flood that flowed across the entire figure 1 map area and that was systematically captured by headward erosion of deep northeast-oriented valleys, which diverted flood waters further and further northeast and north. The southeast-oriented flood water source cannot be determined from evidence presented here. However, the floods occurred while the Black Hills area was being uplifted and flood waters can be traced headward (using Missouri River drainage basin landform origins research project essays published on this website) to a former North American ice sheet location. Rapid melting of a thick North American ice sheet located in a deep “hole” would explain the flood water source and also why deep valleys eroded west and southwest to capture southeast-oriented flood waters to divert flood waters further and further northeast into space in the deep “hole” the rapidly melting ice sheet had once occupied. In addition, presence of a thick North American ice sheet in a deep “hole” north and east of the Black Hills might explain crustal warping that uplifted the Black Hills dome during or even after an immense southeast-oriented flood. Uplift of the Black Hills dome may have been accelerated by crustal unloading as flood waters deeply eroded the Black Hills region and removed overlying rock layers.

Inyan Kara Creek-Stockade Beaver Creek drainage divide area detailed location map

Figure 2 provides a slightly more detailed map for the Inyan Kara Creek-Stockade Beaver Creek drainage divide area. Lawrence, Pennington, and Custer Counties are located in western South Dakota. Weston and Crook Counties are located in northeast Wyoming (Crook County is north of Weston County). Inyan Kara Creek originates as northwest-oriented Soldier Creek north of Four Corners, Wyoming and flows around Inyan Kara Mountain and then northwest to join the northeast-oriented Belle Fourche River downstream from the Keyhole reservoir area. Stockade Beaver Creek is shown and labeled and flows northwest to the Four Corners, Wyoming area (north of Newcastle) and then turns abruptly south to flow to southeast oriented Beaver Creek, which flows to the southeast oriented Cheyenne River. Green areas represent Black Hills National Forest lands in South Dakota, which are generally located in the Black Hills upland region (although there are Wyoming Black Hills upland areas as well). Note how the Belle Fourche River flows northeast to the Black Hills north end, where north of the figure 2 map area it turns southeast to flow to the northeast-oriented Cheyenne River. The Cheyenne River begins west and south of the figure 2 map area and flows around the Black Hills south end before turning northeast to join the Belle Fourche River. Southeast-oriented drainage in Weston County, Wyoming is flowing to the southeast oriented Cheyenne River. Also note the large number of southeast-oriented and northwest-oriented tributaries flowing to the northeast-oriented Belle Fourche River. This predominance of southeast- and northwest-oriented tributaries is evidence the northeast-oriented Belle Fourche River valley eroded headward across multiple southeast-oriented flood flow routes, such as might be found in a large-scale anastomosing channel complex, and captured significant southeast-oriented flood flow that had been moving around the Black Hills south end. Headward erosion of a deep northeast-oriented valley across southeast-oriented flood flow channels captured the southeast-oriented flood waters and enabled southeast-oriented tributary valleys to erode headward from the newly eroded Belle Fourche River valley wall.

• At the same time capture of southeast-oriented flood flow beheaded southeast-oriented flood flow routes and flood waters on northwest ends of those beheaded flood flow channels reversed flow direction to flow northwest into the newly eroded and deeper northeast oriented Belle Fourche River valley. Because channels were anastomosing (meaning they were interconnected) reversed flow on beheaded flood flow routes often captured flood waters from yet to be beheaded flood flow routes further to the south or southwest. Capture of water from such yet to be beheaded flood flow routes frequently provided sufficient water to erode significant northwest-oriented tributary valleys. Prior to headward erosion of the deep northeast oriented Belle Fourche River valley flood waters were flowing to what was then the newly eroded southeast and northeast oriented Cheyenne River valley. The Stockade Beaver Creek valley eroded north to capture southeast-oriented flood flow that had been flowing across the Black Hills central core. This diversion of flood waters south may have been aided by Black Hills uplift and was ended when headward erosion of the deep northeast- and southeast-oriented Belle Fourche River valley captured all of the southeast-oriented flood flow, which resulted in a reversal of flow on the northwest ends of beheaded flood flow routes, which eroded northwest-oriented Belle Fourche River tributary valleys, including the northwest-oriented Inyan Kara Creek valley.

Inyan Kara Creek-Mason Creek-Skull Creek drainage divide area

Figure 3: Inyan Kara Creek-Mason Creek-West Fork Skull Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Figure 3 illustrates the Inyan Kara Creek-Skull Creek drainage divide northeast of Upton, Wyoming. Inyan Kara Mountain is located in the figure 3 northeast corner. Mason Creek flows west-southwest from its origin south of Inyan Kara Mountain to join northwest-oriented Dry Creek in the Gravel Pit area in the figure 3 center and Mason Creek then turns northwest to flow to Inyan Kara Creek north of the figure 3 map area. East of Inyan Kara Mountain along the figure 3 north edge Inyan Kara Creek can be seen flowing southeast and then turning northwest to join northwest-oriented Mason Creek north of the figure 3 map area (figure 9 illustrates the region north of figure 3). Inyan Kara Creek flows to the northeast-oriented Belle Fourche River, which flows around the Black Hills north end. South of the Mason Creek headwaters area in the figure 3 east center the West Fork Skull Creek flows west through a water gap and then southwest and south to join south-oriented Skull Creek west of the Skull Creek town site in the figure 3 southeast corner. Skull Creek flows eventually to the southeast-oriented Cheyenne River, which flows around the Black Hills south end. Note through valleys in figure 3 linking the northeast-oriented Belle Fourche River and southeast-oriented Cheyenne River drainage basins. These through valleys provide evidence that at one time water flowed from what is today the northeast-oriented Belle Fourche River drainage basin to the Cheyenne River drainage basin and that for a time at least (when headward erosion of the Belle Fourche River valley was capturing the southeast-oriented flood waters and just beginning to reverse flood waters on the northwest ends of beheaded flood flow routes) flood waters in this figure 3 map area were moving south around the Black Hills south end and also moving northeast around the Black Hills north end. Remember, today the Belle Fourche River joins the Cheyenne River east of the Black Hills, which means flood waters were eroding deep valleys completely around what is today the Black Hills uplift area. Other essays (see essays under Black Hills region on sidebar category list) describe how prior to erosion of the deep Cheyenne River and Belle Fourche River valleys around the Black Hills flood waters flowed across what is today the high Black Hills upland area, which meant the Black Hills upland area did not stand high above the surrounding region as it does today. The best explanation for the diversion of flood flow from routes across the present day Black Hills upland area to what are today the Cheyenne River and Belle Fourche River valleys around the Black Hills upland area is the Black Hills uplift was occurring as flood waters crossed what is today the Black Hills upland region.

Inyan Kara Creek-Skull Creek-Cold Springs drainage divide area

Figure 4 illustrates drainage divides between the northwest-oriented Inyan Kara Creek drainage basin (draining to the northeast-oriented Belle Fourche River), the south-oriented Skull Creek drainage basin (draining to the southeast-oriented Cheyenne River), and northwest-oriented Cold Springs Cree, which is a tributary to northeast-oriented Redwater River (which drains to the southeast-oriented Belle Fourche River) and illustrates a region southeast of the figure 3 map area and provides overlap with figure 3. The West Fork Skull Creek originates north of Strawberry Mountain and flows west through a water gap in the figure 4 northwest corner and then southwest as seen in figure 3. Skull Creek originates south of Strawberry Mountain and also flows west-southwest through a water gap to the Skull Creek town site and to join the south-oriented West Fork Skull Creek as seen in figure 3. Oil Creek originates southeast of Star Butte and flows south-southwest to south-oriented Delaney Canyon in the figure 4 south center and then flows south to eventually join south-oriented Skull Creek and eventually join the Cheyenne River to flow around the Black Hills south end. In the figure 4 southeast corner south-oriented Stockade Beaver Creek can just barely be seen. Northwest-oriented Cold Springs Creek flows across the figure 4 northeast corner and eventually reaches the northeast-oriented Redwater River, which flows to the southeast-oriented Belle Fourche River. Southwest of northwest-oriented Cold Springs Creek is northwest-oriented Soldier Creek, which flows to Inyan Kara Creek north of the figure 4 map area and which after jogging southwest turns northwest to flow to the northeast-oriented Belle Fourche River, which flows around the Black Hills north end. Note how these diverging drainage basins are linked by through valleys indicating at one time water flowed freely from one drainage basin to another. Further, the through valleys provide evidence at least for a time as flood water captures were taking place flood waters were flowing from the figure 4 map area to go both around the Black Hills south end and around the Black Hills north end (and probably also to the Redwater River, which flowed across part of the upland region ). Through valleys also link tributary valleys within the same major drainage basin providing evidence at one time the tributary valleys were channels in  anastomosing channel complexes draining the respective drainage basins.

Detailed map of Skull Creek-Delaney Canyon drainage divide area

Figure 5: Detailed map of Skull Creek-Delaney Canyon drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Figure 5 illustrates a detailed map of the Skull Creek-Delaney Canyon drainage divide area seen in less detail in figure 4. Southwest and west-oriented Skull Creek is located in the figure 5 northwest corner and as illustrated in figures 4 and 3 flows west and then turns to become a south-oriented stream, which eventually reaches the southeast-oriented Cheyenne River to flow around the Black Hills south end. South-oriented Delaney Canyon drains from the figure 5 center (east) to the figure 5 south edge and eventually drains to south-oriented Skull Creek. The southwest oriented valley labeled “Canyon” is Black Canyon and it also drains to south-oriented Skull Creek. Note how the south-oriented Delaney Canyon valley is linked by a well-defined through valley with a northwest-oriented Skull Creek tributary valley. Also note how the southwest oriented Black Canyon valley is linked by a through valley with the south-oriented Delaney Canyon valley and with the northwest-oriented Skull Creek tributary. These through valleys provide evidence at one time water flowed southeast from what is today the west-oriented Skull Creek valley to the south-oriented Delaney Canyon valley and to the southwest oriented Black Canyon valley. At the same time water must have been flowing south in what is today the south-oriented Skull Creek valley seen in figure 3 above. In other words evidence presented here documents three south-oriented anastomosing channels that carried flood waters south to what was probably the actively eroding southeast-oriented Cheyenne River valley. The anastomosing channel complex was dismembered as the Delaney Canyon valley eroded headward to capture flood waters that had been moving southwest to the Black Canyon valley and then as a deeper Skull Creek valley eroded north to capture and reverse southeast-oriented flood flow that had been moving to the Delaney Canyon valley. Flood waters on the west end of that beheaded flood flow route reversed flow direction to flow west and southwest to the deeper Skull Creek valley and probably captured yet to be beheaded southeast-oriented flood flow moving further to the northeast. The reversed flood flow then eroded a deeper southwest and west oriented Skull Creek valley before all southeast-oriented flood flow to the Skull Creek drainage basin was captured by headward erosion of the deep northeast-oriented Belle Fourche River valley further to the northwest.

Cold Springs Creek-Soldier Creek-Stockade Beaver Creek drainage divide area

Figure 6: Cold Springs Creek-Soldier Creek-Stockade Beaver Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Figure 6 illustrates the Cold Springs Creek-Soldier Creek-Stockade Beaver Creek drainage divide area northeast of Four Corners, Wyoming, which is located near the Wyoming-South Dakota state line. Crook and Weston Counties are in Wyoming and Pennington and Lawrence Counties are in South Dakota. Stockade Beaver Creek is located in the figure 6 southeast corner. Headwaters of Stockade Beaver Creek flow northwest from South Dakota into Wyoming and then turn abruptly to flow south and to eventually reach the southeast-oriented Cheyenne River which flows around the Black Hills south end. Just north of the Stockade Beaver Creek elbow of capture at State Line Spring, Soldier Creek originates and flows northwest into the figure 6 northwest quadrant and then north of figure 6 to Inyan Kara Creek, which after making some jogs flows northwest to the northeast-oriented Belle Fourche River, which flows around the Black Hills north end. Just to the northeast of Soldier Creek is parallel Cold Springs Creek, which flows west from South Dakota to Buckhorn, Wyoming and then northwest to the figure 6 north center edge and eventually to the northeast-oriented Redwater River and the southeast-oriented Belle Fourche River. Note the deep well-defined north-south through valley extending south from the Lawrence County southwest corner along the figure 6 east edge. That through valley links the Cold Spring Creek valley with the Stockade Beaver Creek valley and with south-oriented Stockade Beaver Creek tributary valleys (see Stockade Beaver Creek-Red Canyon Creek drainage divide essay and provides evidence the northwest-oriented Cold Spring Creek valley originated as a southeast-oriented flood flow route that moved water south to the southeast-oriented Cheyenne River valley and around the Black Hills south end. Headward erosion of the deep southeast-oriented Belle Fourche River valley along the Black Hills northeast flank and the deep Redwater River valley and tributary valleys beheaded southeast flow on the Cold Springs Creek route and caused a reversal of flow on the northwest end of the beheaded flood flow route to create the northwest-oriented Cold Spring Creek valley. Less obvious through valleys also link the northwest-oriented Soldier Creek valley with the south-oriented Stockade Beaver Creek valley and tributary valley system and provide evidence the northwest-oriented Soldier Creek valley originated as a southeast-oriented flow route moving flood waters around the Black Hills south end (see figure 7 below). Headward erosion of the deep Belle Fourche River valley around the Black Hills north end beheaded southeast-oriented flood flow that caused a reversal of flood flow on the northwest ends of the beheaded flood flow routes that enabled the reversed Inyan Kara Creek-Soldier Creek drainage network to evolve.

Detailed map of Soldier Creek-Stockade Beaver Creek drainage divide area

Figure 7: Detailed map of Soldier Creek-Stockade Beaver Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Figure 7 provides a detailed map of the Soldier Creek (Inyan Kara Creek)-Stockade Beaver Creek drainage divide area seen in less detail in figure 6 above. Soldier Creek flows northwest from the State Line Spring to the figure 7 northwest corner. North-oriented drainage in the figure 7 northeast corner flows to northwest-oriented Cold Springs Creek. The north-south through valley linking northwest-oriented Cold Springs Creek, northwest-oriented Dry Beaver Creek headwaters, a northwest-oriented Stockade Beaver Creek tributary headwaters, and south-oriented Stockade Beaver tributary headwaters is located along the figure 7 east edge. Dry Beaver Creek flows northwest in the figure 7 southeast quadrant to the south-oriented Stockade Beaver Creek valley in the figure 7 south center. Note the through valley just south of the State Line Spring linking the northwest-oriented Soldier Creek valley with the south-oriented Stockade Beaver Creek valley. Also note the southwest-oriented Soldier Creek headwaters stream flowing from South Dakota to the northwest-oriented Soldier Creek valley at State Line Spring and how that southwest-oriented headwaters valley is linked by a through valley with a southeast-oriented valley draining to the north-south through linking Cold Springs Creek and Stockade Beaver Creek. Further, note the northwest-southeast oriented through valley north of the northwest-oriented Dry Beaver Creek valley that links the north end of the south-oriented Stockade Beaver Creek valley with a southwest-oriented Dry Beaver Creek tributary valley. And the list of through valleys linking figure 7 drainage basins could continue. These through valleys provide evidence of an anastomosing southeast-oriented channel complex that was captured by headward erosion of deep south-oriented Stockade Beaver Creek tributary valleys and then the south-oriented Stockade Beaver Creek valley. Subsequently headward erosion of the Redwater River northwest of the figure 7 map area beheaded flood flow on the Cold Springs Creek valley route and caused a reversal of flow on the northwest end of the beheaded flood flow route that resulted in the present day northwest-oriented Cold Springs Creek valley. About the same time headward erosion of the south-oriented Skull Creek valley system captured much flood flow and may have initiated flood flow reversals in the eastern half of the present day Inyan Kara Creek drainage basin (including Soldier Creek). Shortly thereafter headward erosion of the northeast-oriented Belle Fourche River valley beheaded southeast-oriented flood flow to what is now the Inyan Kara Creek drainage basin. Flood waters in the present day Inyan Kara Creek drainage basin reversed flow direction to flow northwest to the deeper northeast-oriented Belle Fourche River valley, and that flood flow reversal was what captured northwest-oriented flow on what is the present day northwest-oriented Soldier Creek valley.

Oil Creek-Sweetwater Creek drainage divide area

Figure 8: Oil Creek-Sweetwater Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software. 

Figure 8 illustrates the region south of the figures 4 and 6 map areas and includes overlap areas with both previous figures. Northwest-oriented Soldier Creek and the State Line Spring are located in the figure 8 northeast corner. South of the State Line Spring Stockade Beaver Creek flows south just west of the Wyoming-South Dakota border. Southwest-oriented Skull Creek is located in the figure 8 northwest corner and south of Skull Creek is the south-oriented Delaney Canyon (seen in detail in figure 5). Delaney Canyon drains into south-southwest and south oriented Oil Creek, which eventually joins south-oriented Skull Creek. Flowing northwest from the figure 8 center to south-southwest oriented Oil Creek is Red Creek. South of the northwest-oriented Red Creek headwaters is south-southeast oriented Sweetwater Creek, which flows to Salt Creek, which in turn flows to south-oriented Stockade Beaver Creek. Note how Red Creek headwaters and Sweetwater Creek headwaters are linked by a through valley. Between south-oriented Oil Creek and south-oriented Sweetwater Creek is south-oriented West Plum Creek. West Plum Creek is an Oil Creek tributary, which means it is part of the south-oriented Skull Creek drainage basin. Northwestern Table located between Sweetwater Creek and West Plum Creek in the figure 8 south center is the drainage divide between the south-oriented Stockade Beaver Creek drainage basin to east and the south-oriented Skull Creek drainage basin to west. Note North Draw along the figure 8 south center edge just south of Northwestern Table. North Draw is the headwaters of southwest-oriented East Plum Creek, which joins West Plum Creek and eventually reaches Skull Creek, and which is linked by a through valley along the figure 8 south edge to the south-oriented Sweetwater Creek valley. The Red Creek-Sweetwater Creek through valley and the Sweetwater Creek-East Plum Creek through valleys (among others) provide evidence that headward erosion of the Sweetwater Creek valley beheaded south-oriented flood flow to the East Plum Creek valley and that headward erosion of the Oil Creek valley beheaded southeast-oriented flood flow to the Sweetwater Creek valley. Additional through valleys can also be seen in figure 8. For example there is a through valley linking the headwaters of the south-oriented West Plum Creek with the south-southwest oriented Oil Creek valley. That through valley provides evidence the Oil Creek valley eroded headward to behead south-oriented flood flow to the West Plum Creek valley. In other words these valleys were eroded as channels in an ever-changing south-oriented anastomosing channel complex, with deeper channels beheading flow routes to shallower channels.

Beaver Creek-Inyan Kara Creek drainage divide area

Figure 9: Beaver Creek-Inyan Kara Creek drainage divide area.

Figure 9 illustrates an Inyan Kara Creek drainage basin area north of the figure 3 map area and includes overlap areas with figure 3. Inyan Kara Creek flows northwest in the figure 9 southeast corner and then west, southwest, northwest, and southwest to join northwest oriented Mason Creek in the figure 9 southwest corner. Northwest-oriented Soldier Creek joins northwest oriented Inyan Kara Creek in the figure 9 southwest corner. Beaver Creek is the west oriented Inyan Kara Creek tributary originating in the figure 9 north center that joins southwest-oriented Benton Creek to flow to Inyan Kara Creek. Note the Benton Creek-Beaver Creek drainage divide area between Bock Hill and Lime Butte in the figure 9 north center, which is shown in more detail in figure 10. Note also how Beaver Creek headwaters in the Black Flats area are northwest oriented. North-oriented drainage in the figure 9 northeast corner flows eventually to the northeast-oriented Redwater River, which flows to the southeast-oriented Belle Fourche River. Many through valleys link various channels in the complex figure 9 Inyan Kara Creek drainage basin area. For example, the northwest-southeast oriented Black Flats area is located in a large through valley linking the northwest-oriented Inyan Kara Creek headwaters (including northwest-oriented Soldier Creek) with the west and southwest-oriented Beaver Creek valley. Briefly what happened to create the figure 9 drainage patterns was originally the region was eroded by southeast-oriented flood waters that were captured by headward erosion of the deep south-oriented Stockade Beaver Creek valley system. The deep south-oriented Skull Creek valley system eroded north to capture southeast-oriented flood water and probably captured significant flood flow across the figure 9 map area. For example south-oriented Spring Branch flowing from the Kaiser Divide area to Inyan Kara Creek probably was originated as a south-oriented valley eroded by water going to the Skull Creek drainage system as was the present day south-oriented Beaver Creek valley to the west of the south-oriented Spring Branch valley. Headward erosion of what was then the deep south-oriented Beaver Creek and Benton Creek valleys reversed flood flow in the Black Flats area to initiate the northwest- and west-oriented Beaver Creek valley that exists today. Soon thereafter headward erosion of the northeast-oriented Redwater River valley to the north of figure 9 beheaded some of the southeast-oriented flood flow, causing a flow reversal that captured yet to be beheaded flood flow which eroded some of the northeast-oriented valleys. Next headward erosion of the northeast-oriented Belle Fourche River valley to the west of figure 9 beheaded more of the southeast-oriented flood flow routes and caused a reversal of flood flow that enabled reversed flow on the Inyan Kara Creek drainage route to capture what had become significant flow routes moving flood water to the south-oriented Skull Creek valley system.

Detailed map of Benton Creek- Beaver Creek drainage divide area

Figure 10: Detailed map of Benton Creek- Beaver 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 Benton Creek-Beaver Creek drainage divide area, which was shown in less detail in figure 9 above. Benton Creek flows south and southwest from the figure 10 northwest corner to the figure 10 west center edge. Beaver Creek flows northwest in the figure 10 southeast quadrant and then west and southwest to the figure 10 southwest corner. Note how an unnamed Beaver Creek tributary originates near the figure 10 north edge (northeast of Bock Hill) and flows south and southeast to join west-oriented Beaver Creek as a barbed tributary southwest of Lime Butte. Also note how Cunday Creek originates further to east along the figure 10 north edge and flows southeast toward Lime Butte before turning south (and jogging west and then south) to join west-oriented Beaver Creek, also southwest of Lime Butte. Originally the figure 10 map area was eroded by southeast oriented flood flow, which was flowing in multiple anastomosing channels  across the Black Flats area (southeast of figure 10) to the south-oriented Stockade Beaver Creek drainage network. Headward erosion of the deep Skull Creek valley network to the south of figure 10 (and figure 9) probably next eroded the present day south-oriented Beaver Creek valley segment north and the southwest-oriented Benton Creek valley northeast to capture southeast oriented flood flow and to divert the water south to what was then the actively eroding Skull Creek valley system. It was during this phase of the drainage history that flood flow on what are today the northwest and west-oriented Beaver Creek valley segments were probably reversed. The reversal occurred shortly before the southwest-oriented Benton Creek valley had eroded far enough northeast to behead southeast-oriented flood flow to the unnamed southeast-oriented Beaver Creek tributary (originating northeast of Bock Hill) and to southeast- and south-oriented Cunday Creek. Subsequently flood flow in the evolving Beaver Creek drainage system was captured by reversed flood flow on the Inyan Kara Creek route and diverted from flowing south to Skull Creek and then around the Black Hills south end to flowing west and northwest along the Inyan Kara Creek route to the northeast-oriented Belle Fourche River and then around the Black Hills north end. There is much more that could be said about Inyan Kara Creek history, but this brief description hopefully can provide future workers place to start.

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.