Cheney, PA is located in an east oriented East Branch Chester Creek valley segment and is located a short distance downstream from the confluence of south-southeast oriented East Branch Chester Creek with southeast oriented Goose Creek and a short distance upstream from where the East Branch Chester Creek turns to flow again in a south-southeast direction. Most tributaries from the southwest flow in northeast directions to join Goose Creek and the East Branch Chester Creek as barbed tributaries and some tributaries from the northeast flow in southwest directions to join the East Branch Chester Creek as barbed tributaries. The northeast and southwest orientations of the East Branch Chester Creek and Goose Creek tributaries suggests an aligned drainage may be present.
Figure 1: East Branch Chester Creek and Goose Creek valleys and tributaries in the Cheney, PA area. Cheney and Cheney University are located near the center of figure 1. See text for detailed discussion. United States Geological Survey map digitally presented using National Geographic TOPO software.
Figure 1 illustrates how East Branch Chester Creek flows in a south-southeast and south direction to join southeast oriented Goose Creek west of Cheney University and then to flow in an east direction before turning to flow in a south-southeast direction near the east edge of figure 1. Most East Branch Chester Creek and Goose Creek tributaries from the south seen in figure 1 are oriented in northeast and north directions and join the south-southeast oriented East Branch Chester Creek and its southeast oriented Goose Creek tributary as barbed tributaries. Interestingly tributaries from the north also join the East Branch Chester Creek as barbed tributaries. For example, Westtown Run flows in a south-southwest and southwest direction to join East Branch Chester Creek as a barbed tributary just north of where East Branch Chester Creek turns to flow in an east direction. East of Cheney University a south-southwest oriented stream joins East Branch Chester Creek as a barbed tributary and near the east edge of figure 1 a south-southeast oriented stream turns in a south-southwest direction to also join East Branch Chester Creek as a barbed tributary. The predominance of northeast and southwest oriented streams and valleys seen in figure 1 suggests the presence of an aligned drainage network.
The northeast and southwest orientation of the secondary valleys, or the aligned drainage, is probably evidence of a southwest oriented anastomosing channel complex that existed at the time the deeper primary valleys eroded headward from what was at that time a newly eroded Delaware River. The channel complex was probably formed by massive and prolonged southwest oriented flood flow. Southeast Pennsylvania evidence is not adequate to determine the flood flow source, although evidence described in the Millstone River entry suggests the floodwaters flowed from the Long Island Sound area across New Jersey to reach southeast Pennsylvania. Volumes of water were immense suggesting melt water derived from a large continental ice sheet may have been the flood flow source, although ice sheet history as presently described in the geologic literature does not suggests melt water floods of the magnitude required to erode the southeast Pennsylvania landforms. The landforms exist and need to be explained, which means eventually the published ice sheet history will have to be revised.
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