A geomorphic history based on topographic map evidence
Abstract:
The White River-Little White River drainage divide area discussed here is located in southern South Dakota, USA. Although detailed topographic maps of the White River-Little White River drainage divide area have been available for more than fifty years detailed map evidence has not previously been used to interpret the region’s geomorphic history. The interpretation provided here is based entirely on topographic map evidence. The White River-Little White River drainage divide area, which includes Pine Ridge Escarpment areas, is interpreted to have been eroded during immense southeast-oriented flood events, the first of which flowed on a topographic surface at least as high as the highest points in the present-day drainage divide area. Flood erosion of the White River-Little White River drainage divide area ended when headward erosion of a deep and immense east-oriented White River valley captured the southeast-oriented flood flow.
Preface:
The following interpretation of detailed topographic map evidence is provided as evidence in the Missouri River drainage basin landform origins research project, which is compiling similar evidence for all major drainage divides contained within the Missouri River drainage basin and for all major drainage divides with and within certain adjacent drainage basins. The research project is interpreting evidence in the context of a previously unexplored geomorphology paradigm, which is briefly described in the introduction below. Project essays are listed on the sidebar category list under their appropriate Missouri River tributary drainage basin, Missouri River segment drainage basin (by state), and/or state in which the Missouri River drainage basin is located.
Introduction
- The purpose of this essay is to use topographic map interpretation methods to explore South Dakota White River-Little White River 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 South Dakota White River-Little White River drainage divide area landform evidence will be regarded as evidence supporting the “thick ice sheet that melted fast” paradigm.
White River-Little White River drainage divide area general location map
Figure 1: White River-Little White River drainage divide area general location map. National Geographic Society map digitally presented using National Geographic Society TOPO software.
Figure 1 provides a White River-Little White River drainage divide area location map. The White River originates in northwest Nebraska, west and southwest of Chadron and flows northeast to the South Dakota Badlands National Park area where it turns to flow in a more easterly direction to the southeast-oriented Missouri River. The Little White River begins southeast of the Badlands National Park region near Batesland, South Dakota and flows roughly in an east direction, along what the detailed maps below will show to be the rim of the north-facing Pine Ridge Escarpment, until turning north-northeast to flow to the east oriented White River. North of the northeast and east oriented White River is the northeast oriented Cheyenne River and the east-northeast oriented Bad River, which originates near the Badlands National Park east end. The Cheyenne River-White River drainage divide area essay and Bad River-White River drainage divide area essay address landform evidence north of the study region here and can be found under White River on the sidebar category list. East of the north-northeast oriented White River segment is the southeast-oriented Keya Paha River and the White River-Keya Paha River drainage divide area essay addresses evidence in that region. South of the east-oriented Little White River segment is the northeast and east-oriented Niobrara River and another essay addresses Little White River-Niobrara River drainage divide evidence (found under White River or Niobrara River on sidebar category list). This essay interprets White River-Little White River drainage divide landform origins in the context of an immense southeast-oriented flood that flowed over most or all of the figure 1 map area on a topographic surface at least as high as the present day High Plains south of the Pine Ridge Escarpment rim. That southeast-oriented flood was systematically captured by headward erosion of east- and northeast oriented valleys of which the northeast and east-oriented Niobrara River valley was one. Subsequent to Niobrara River valley headward erosion a much deeper and larger east oriented valley eroded west along the what is today the east-oriented White River alignment. The north-northeast oriented Little White River valley eroded south-southwest from what was then the actively eroding White River valley head and then west to capture southeast-oriented flood flow that had not yet been captured by headward erosion of the deep and large east-oriented White River valley. Subsequently headward erosion of the deep and large White River valley captured all southeast-oriented flood flow to the Little White River valley and today the north-facing Pine Ridge Escarpment slope is the deeply eroded south wall of the deep and large east-oriented White River valley that eroded west at that time.
White River-Little White River drainage divide area detailed location map
Figure 2: White River-Little White River drainage divide area detailed location map. United States Geological Survey map digitally presented using National Geographic Society TOPO software.
Figure 2 provides a more detailed location map for the White River-Little White River drainage divide area. The Little White River headwaters are located near Batesland in the Pine Ridge Indian Reservation in southeast Shannon County, South Dakota in the figure 2 southwest quadrant. East of the Batesland area is north-northwest-oriented Wounded Knee Creek, which flows to the northeast-oriented White River near the figure 2 west center edge. North-northwest-oriented Porcupine Creek flows from northwest of the Batesland area to the northeast-oriented White River. East of Porcupine Creek other northwest-oriented White River tributaries shown include Medicine Root Creek (with American Horse Creek and No Flesh Creek as major northwest-oriented tributaries), Bear-in-the-Lodge Creek (which flows southeast before turning northwest), Pass Creek (which is north-oriented with northwest-oriented tributaries) and Black Pipe Creek (which is a north-oriented with northwest-oriented tributaries). Also important to this discussion will be east and northeast-oriented Cottonwood Creek (east of Black Pipe Creek), which has southeast-oriented headwaters and which flows to the White River just west of where the Little White River joins the White River. Note how the northwest-oriented Bear-in-the-Lodge Creek alignment is the same as the Little White River southeast-orientation in eastern Bennett County, South Dakota, which also is the same as the southeast-oriented Minnechaduza Creek alignment southeast of the Little White River elbow of capture (Minnechaduza Creek flows southeast into Nebraska south of the Rosebud Indian Reservation in the figure 2 southeast corner). This northwest-southeast drainage alignment along with the northwest-oriented alignment of many White River tributaries and the southeast-orientation of many Little White River tributaries is evidence southeast-oriented flood water flowed over the entire figure 2 region, probably in what was an immense southeast-oriented anastomosing channel complex. Northwest-oriented tributary valleys were eroded by reversals of flood water on the northwest ends of beheaded southeast-oriented flood flow channels. Reversed flow was probably aided in eroding northwest-oriented tributary valleys by the capture of flood flow from yet to be beheaded flood flow channels further to the west and southwest. Detailed maps below will illustrate evidence supporting this interpretation.
Wounded Knee Creek-Stinking Water Creek drainage divide area
Figure 3: Wounded Knee Creek-Stinking Water Creek drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.
Figure 3 illustrates the westernmost extremity of the Little White River drainage basin near Batesland, South Dakota. Stinking Water Creek (figure 3 southeast quadrant) flows northwest and north before turning east to flow to the Little White River (east of figure 3) and is the westernmost Little White River tributary. Hills is the figure 3 southeast corner appear to be sand hills extending north from the western Nebraska sand hills region. Northwest-oriented Stinking Water Creek headwaters appear to be on the same alignment as northwest oriented Bartlett Creek, which flows to north-northwest oriented Wounded Knee Creek near Wounded Knee, South Dakota. Headwaters of north-northwest oriented Porcupine Creek flow north just east of Porcupine Butte and further east in the figure 3 northeast quadrant are north-oriented headwaters of northwest oriented American Horse Creek. This evidence suggests the east-oriented Stinking Creek valley was eroded west to capture southeast-oriented flood flow and the northwest- and north-oriented Stinking Water Creek valley was developed as a reversal of flood flow on the northwest end of a beheaded southeast-oriented flood flow route to the Niobrara River valley (located in Nebraska south of the figure 3 map area). The beheaded flood flow route was using what is today the Wounded Knee Creek-Bartlett Creek alignment and probably provided significant flood flow to actively eroding Little White River valley before being beheaded and reversed by headward erosion of the large and deep White River valley. Flood waters moving east in the newly eroded Little White River valley probably spilled out of the valley and were captured by reversed flood waters on what are today other north- and north-northwest oriented White River tributaries, which accounts for the water source responsible for eroding the north and north-northwest oriented White River tributary valleys. Reversal of flood flow on Wounded Knee-Bartlett Creek flood flow route was responsible for eroding that north-northwest oriented valley and was aided by flood waters captured from west of the figure 3 map area.
Medicine Root Creek-Little White River drainage divide area
Figure 4: Medicine Root Creek-Little White River drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.
Figure 4 illustrates the White River-Little White River drainage divide area northeast of the figure 3 map area. There is overlap with figure 3 with Bateland, South Dakota being located in the southwest corner. Also, figure 4 has been reduced more than normal to provide a big picture view, which has the disadvantage of making names hard to read. Stinking Water Creek flows northeast to join the southeast and northeast-oriented Little White River south of Swett, South Dakota in the figure 4 center south. Martin, South Dakota is the town at the highway junction in the figure 4 southeast quadrant. South of Martin, and south of the Little White River, along the figure 4 south edge is east-oriented Lake Creek, which flows to the Little White River east of the figure 4 map area. Northwest-oriented American Horse Creek flows to the figure 4 northwest corner and east of American Horse Creek is northwest-oriented No Flesh Creek (with the red highway going through Yellow Bear Canyon). Southeast of No Flesh Creek headwaters are northeast headwaters of Bear-in-the-Lodge Creek, which flow from Swett to Allen, South Dakota near the escarpment rim and then turn to flow southeast and then east in a narrow valley which descends down the escarpment slope to the figure 4 east center edge. Northeast-oriented drainage flowing to the figure 4 northeast corner is Pretty Hip Creek, which flows to northwest-oriented Bear-in-the-Lodge Creek, which makes a remarkable U-turn east of the figure 4 map area. Between the Pretty Hip Creek drainage basin and the northwest-oriented No Flesh Creek drainage basin to west is north-northeast oriented Corn Creek, which also flows to the northwest-oriented Bear-in-the-Lodge Creek. Events recorded by this figure 4 map evidence begin with southeast-oriented flood water flowing across the entire figure 4 map area. Headward erosion of the Little White River next captured the southeast-oriented flood flow (which had not yet been beheaded by headward erosion of the deep White River valley to the north) and diverted the southeast-oriented flood water to the east and then north-northeast into what was then the actively eroding deep White River valley. As the deep White River valley was eroded west it systematically beheaded and reversed flood flow on northwest ends of beheaded flood flow routes. Reversed flow on those beheaded flood flow routes often captured flood water from yet to be beheaded flow routes further to the west. The southeast-oriented Bear-in-the-Lodge Creek valley segment is evidence of how such captures occurred. As the deep White River valley beheaded southeast-oriented flood flow routes and reversed flood flow on the northwest ends of those beheaded flood flow it also created the White River-Little White River drainage divide.
Bear-in-the-Lodge Creek-Little White River drainage divide area
Figure 5: Bear-in-the-Lodge Creek-Little White River drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.
Figure 5 illustrates the White River-Little White River drainage divide area east of the figure 4 map area and includes some overlap area with figure 4. The Little White River flows northeast and southeast in the figure 5 south center and southeast quadrant. Lake Creek is the northeast-oriented tributary joining the Little White River. Bear-in-the-Lodge Creek flows southeast on the figure 5 west center edge and jogs northeast, east, and northeast before turning northwest to flow to the figure 5 north edge. Pretty Hip Creek flows north-northeast in the figure 5 northwest corner. Northwest-oriented Spring Creek flows in a broad valley from the White Lake area to join northwest-oriented Bear-in-the-Lodge Creek. Note how the northwest-oriented Bear-in-the-Lodge Creek and Spring Creek valleys are in approximately the same alignment as the southeast oriented Little White River segment in the figure 5 southeast corner. This alignment of major northwest-southeast oriented valleys is evidence the valleys originated as a major southeast oriented flood flow route, which was first captured further to the east by headward erosion of the north-northeast oriented Little White River valley (see figure 6 and 7). The Little White River valley eroded southwest and west from the White Lake area to capture southeast oriented flood flow moving on flood flow routes or channels southwest of the Bear-in-the-Lodge-Spring Creek flood flow route alignment. The northeast-oriented Bear-in-the-Lodge Creek valley segment was probably initiated on a higher level topographic surface as a tributary to capture southeast-oriented flow before the flood flow reached the Little White River valley and the southeast-oriented Bear-in-the-Lodge Creek segment provides evidence such capture did take place. Subsequently headward erosion of the deep White River valley to the north beheaded southeast-oriented flood flow on the Bear-in-the-Lodge Creek-Spring Creek alignment causing flood waters on the northwest end of that beheaded flood flow route to reverse flow direction and to begin to erode a northwest-oriented valley. The southeast- and northeast-oriented Bear-in-the-Lodge Creek extension continued to receive significant yet to be captured southeast-oriented flood flow, which helped erode the regional landscape and the Bear-in-the-Lodge Creek valley prior to beheading of those southeast-oriented flood flow routes by White River valley headward erosion to the north and west.
Pass Creek-Little White River drainage divide area
Figure 6: Pass Creek-Little White River drainage divide area. United States Geological Survey map digitally presented using National Geographic Society TOPO software.
Figure 6 illustrates the White River-Little White River drainage divide area east of the figure 5 map area and includes some overlap areas. The southeast oriented Little White River valley flows from the figure 6 west center to the figure 6 south center. The Little White River then turns northeast just south of figure 6 and flows east-northeast across the figure 6 southeast corner. North-oriented Black Pipe Creek headwaters are present in the figure 6 north center, just west of the Indian Reservation boundary. East-northeast-oriented Phister Creek flows to the southeast and northeast-oriented Cut Meat Creek in the figure 6 northeast corner. Cut Meat Creek then flows to the Little White River. Headwaters of north-northwest oriented Pass Creek are located in the figure 6 northwest corner. The large southeast-oriented Little White River valley along what is today the Pine Ridge Escarpment rim is evidence the Bear-in-the-Lodge Creek-Spring Creek-southeast-oriented Little White River alignment was for a time a major southeast-oriented flood flow channel (probably one of many in a large southeast-oriented anastomosing channel complex). Hills around the escarpment rim reach over 1000 meters in elevation. The present day White River valley floor south of those hills is approximately 900 meters in elevation, meaning the flood waters eroded a 100-meter deep southeast-oriented valley here before the deep White River valley to the north existed. Today it is hard to image where southeast-oriented flood waters capable of eroding a 100-meter deep valley could have come from, but they came from northwest of the present day Pine Ridge Escarpment and flowed on a topographic surface which no longer exists. Evidence in this essay is not adequate to determine the flood water source, although by using evidence from numerous Missouri River drainage basin landform origins research project essays (published on this website) flood waters can be traced headward to a North American ice sheet location. Rapid melting of a thick North American ice sheet would be a logical flood water source. Further, if that thick North American ice sheet through its weight and erosive actions had created a deep “hole” in the North American continent, headward erosion of deep valleys from that deep “hole” margin to capture south-oriented melt water floods would be a logical event as the ice sheet melted and opened up space the ice sheet had once occupied.
Little White River elbow of capture near Crazy Horse Canyon
Figure 7: Little White River elbow of capture near Crazy Horse Canyon. United States Geological Survey map digitally presented using National Geographic Society TOPO software.
Figure 7 illustrates the Little White River elbow of capture and Crazy Horse Canyon area located southeast of the figure 6 map area and includes overlap areas. Figure 7 shows where headward erosion of the north-northeast oriented Little White River valley segment from what was then the actively eroding deep White River valley head captured southeast oriented flood flow on what was then a major southeast oriented flood flow channel following the present day northwest-oriented Bear-in-the-Lodge Creek and Spring Creek alignment seen in figure 5 and the southeast oriented Little White River valley alignment seen in figure 6. Prior to capture by the north-northeast oriented Little White River valley the southeast-oriented flood flow route continued to the southeast as is evident from the large through valley now occupied by northwest-oriented Spring Creek and continuing southeast of figure 7 to the southeast-oriented Minnechaduza Creek valley, which joins the east-oriented Niobrara River valley at Valentine, Nebraska. In other words, headward erosion of the north-northeast oriented Little White River valley beheaded a major southeast-oriented flood flow route that had been supplying southeast-oriented flood water to what was then the actively eroding east-oriented Niobrara River valley and diverted the flood flow northeast to what was then the actively eroding and much deeper east-oriented White River valley. Note southeast-oriented tributaries to northeast-oriented Beads Creek west of Crazy Horse Canyon and also northwest-oriented Omaha Creek and other northwest-oriented Little White River east of Crazy Horse Canyon. These southeast- and northwest-oriented tributaries are evidence the north-northeast oriented Little White River valley eroded headward to capture multiple southeast-oriented flood flow routes as might be expected in a large southeast-oriented anastomosing channel complex. The northwest-oriented tributaries developed when flood waters on the northwest ends of beheaded southeast-oriented flood flow routes reversed flow direction to flow northwest into the newly eroded and deep capturing valley.
Black Pipe Creek-Little White River drainage divide west of Soldier Creek
Figure 8: Black Pipe Creek-Little White River drainage divide west of Soldier Creek. United States Geological Survey map digitally presented using National Geographic Society TOPO software.
Figure 8 illustrates the Black Pipe Creek-Little White River drainage divide area north of the figure 6 map area and includes a very thin strip of overlap area. Figures 8 and 9 will follow the Little White River valley downstream from the Crazy Horse Canyon area observed in figure 7 to illustrate how the Pine Ridge Escarpment slope was eroded by southeast-oriented flood waters diverted to flow to the newly eroded and actively eroding and deep east-oriented White River valley. The Little White River flows north-northeast through Soldier Creek, South Dakota to the figure 8 northeast corner and continues to flow north-northeast through the figure 9 map area to eventually reach the east-oriented White River. Note northwest-oriented Little White River tributaries in the figure 8 southeast corner. These tributaries are evidence headward erosion of the north-northeast oriented Little White River valley beheaded multiple southeast-oriented flood flow routes and flood waters on the northwest ends of those beheaded flood flow routes reversed flow direction to flow northwest to the newly eroded and deeper Little White River valley. Black Pipe Creek flows northeast and turns to flow north-northwest in the figure 8 northwest corner and continues to flow north (through the figure 10 map area) to eventually reach the east-oriented White River. Cut Meat Creek (headwaters seen in figure 6) flows northeast through Parmelee, South Dakota and then joins with east-southeast oriented Gray Eagletail Creek to flow east-southeast and then northeast to the north-northeast oriented Little White River. Note how Gray Eagletail Creek is flowing in a large northwest-southeast oriented through valley connecting the north-northwest oriented Black Pipe Creek valley with the east-southeast and northeast oriented Cut Meat Creek valley, which drains to the north-northeast oriented Little White River. This through valley is evidence headward erosion of the Little White River valley captured a yet to be beheaded (by what was then headward erosion of the actively eroding and deep east-oriented White River valley) major southeast-oriented flood flow route using the north-northwest Black Pipe Creek alignment and diverted the flood flow east-southeast and then northeast to the north-northeast Little White River and then to the newly eroded and deep east-oriented White River valley from which the deep Little White River valley had eroded south-southwest.
Cottonwood Creek-Little White River drainage divide area west of White River, South Dakota
Figure 9: Cottonwood Creek-Little White River drainage divide area west of White River, South Dakota. United States Geological Survey map digitally presented using National Geographic Society TOPO software.
Figure 9 illustrates the Cottonwood Creek-Little White River drainage divide area north of the figure 8 map area and there is no overlap area. The map has been reduced more than normal to provide a big picture view and names may be hard to read. The White River flows southeast, northeast and southeast in what is today a fairly narrow valley 50-80 meters deeper than the surrounding upland erosion surface. The Little White River flows north to the town of White River, South Dakota and north-northeast before turning northwest to join a northeast-oriented White River valley segment as a barbed tributary. White Thunder Creek flows north-northeast along the figure 9 east edge to join the White River in the figure 9 northeast corner. Pine Creek is the northeast-oriented Little White River tributary flowing from the figure 9 southwest quadrant to join the Little White River just downstream from White River, South Dakota. Cottonwood Creek flows from the figure 9 west center and gradually turns northeast to join the east-oriented White River a short distance west of where the Little White River flows to the White River. Elevations at the town of White River are in the 640-650 meter range and on the White River valley floor to the north are approximately 550 meters. These elevations compare with elevations of over 900 meters along the Pine Ridge Escarpment rim upstream from Crazy Horse Canyon and of over 1000 meters further upstream on the Little White River valley. The entire figure 9 map area appears as though it was eroded by southeast-oriented flood waters which were first captured by headward erosion of the north-oriented White Thunder Creek valley, then by headward of the north-northeast oriented Little White River valley, then by headward erosion of northeast-oriented Pine Creek valley, and next by headward erosion of the Cottonwood Creek valley. These valleys eroded headward as the narrow White River valley seen in figure 9 eroded west. However, that was not the White River valley that carved the Pine Ridge Escarpment. The entire figure 9 is the floor of the large and deep White River valley responsible for carving the Pine Ridge Escarpment as its south wall (all evidence of the north wall was removed by southeast-oriented flood flow from the northwest). The narrow valleys seen in figure 9 were probably carved during the waning stages of the immense southeast-oriented flood that carved the much larger and much deeper valley.
Black Pipe Creek-Cottonwood Creek drainage divide area west of White River, South Dakota
Figure 10: Black Pipe Creek-Cottonwood Creek drainage divide area west of White River, South Dakota. United States Geological Survey map digitally presented using National Geographic Society TOPO software.
Figure 10 illustrates the Black Pipe Creek-Cottonwood Creek, and the Cottonwood Creek drainage divide area west of the figure 9 map area and there is overlap with figure 9. Figure 10 has been reduced more than normal to provide a big picture view and names may be hard to read. The White River flows east, northeast and southeast along the figure 10 top. Black Pipe Creek flows north from the figure 10 south center to join the White River southeast of Belvidere, South Dakota, which is the town north of the White River in the figure 10 northwest quadrant. Cottonwood Creek is the east-oriented stream located in the figure 10 southeast quadrant. A close look at Cottonwood Creek shows its headwaters are southeast-oriented and are linked to northwest White River tributaries and to northwest-oriented Black Pipe Creek tributaries. This evidence suggests the Cottonwood Creek valley eroded west from what must have an actively eroding narrow White River valley head (see figure 9) to capture southeast-oriented flood flow from yet to be beheaded (by headward erosion of the narrow White River valley) flood flow routes. Flood flow routes captured by Cottonwood Creek valley headward erosion were subsequently beheaded as the narrow White River valley eroded southwest and the north-oriented Black Pipe Creek valley eroded south. Once beheaded flood waters on the northwest ends of the beheaded flood flow routes reversed flow direction to initiate erosion of northwest-oriented tributaries to the newly eroded and deeper beheading valley. Again, it is important to remember events that resulted in the erosion of the narrow valleys seen in figure 10 must have occurred during the waning stages of the immense flood, because the events occurred on the floor of a much larger and much deeper that had been previously carved with the north-facing Pine Ridge Escarpment being the eroded south wall of the giant east-oriented White River valley that flood waters had previously eroded west.
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.
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