Figure 2
(see the high resolution version here)
A closer view in 3-D of the terrain surrounding the
Dempsey Divide study area in the Texas panhandle and the western half of
Oklahoma. Note how the interfluvial divides between the rivers of western
Oklahoma lead up onto the crest of the High Plains. These divides would have
formed natural highways for prehistoric east-west travel, being less dissected
and less heavily vegetated than the river bottoms.