The retreating waters started with sheet flow that ultimately deposited the continental shelves. The sheet flow then diminished to channelized currents with ultra high velocities and scale, the only kind of flow powerful enough to form aligned water gaps in a series of perpendicular ridges, seen throughout the Appalachians. This ultra high energy channelized flow stopped so quickly that it left many water gaps high and dry to make wind gaps.
Once again, a creationist explanation is the one that holds water!
Selections from the second section of Origin of Appalachian Geomorphology, Part III: Channelized Erosion Late in the Flood, by Michael J. Oard.
(These selections by Marko Malyj are of the article published in Creation Research Society Quarterly Journal, Volume 48, Number 4, Spring 2012)
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- relief inversion plus reversal in drainage
- the antecedent stream
- the superimposed stream
- stream piracy
"What was written in 1932-33 can still be quoted today: 'The Appalachian problem, like the poor, we shall have with us always.'" (Bryan etal., 1932/3 3, p. 318, quoted in Clark, 1989, p. 225, 229).
If all of the classical uniformitarian hypotheses are insufficient, then we must conclude the necessity of searching for an explanation within a completely different paradigm. Ironically, the features of these landforms readily can be explained by the great nemesis of modern geology- the Genesis Flood. The retreating stage of the Flood, with its two phases, readily accounts for all of these features, including erosion surfaces, plateaus, and the many wind and water gaps cutting through the mountains along its entire length.
Sheet Flow created the Continental Margin
Sheet flow produced extensive erosion surfaces, mainly on the Piedmont and on the plateaus west of the Valley and Ridge Province. As the combination of uplift and base-level decline caused the Appalachian Mountains to emerge from the Flood, the flow diverged from either side of the rising peaks. Sediments eroded west of the Appalachian divide were transported west, where they merged with water flowing east from the rising Rockies, carrying vast amounts of sediment that would form the massive Gulf of Mexico coastal plain and continental margin sediments. Erosion surfaces were later formed on either side of the Appalachian Mountains.
This type of process is seen on a small scale in the breaching of an earth dam by water flowing over its top. Finding a zone of weakness, the sheet flow over the top rapidly cuts a narrow deep notch that channels the water through. Most of the remainder of the dam wall usually remains intact. Also, the anomalously high velocities and the scale of the channelized currents is the only feasible explanation for the phenomenon of aligned water gaps in a series of perpendicular ridges.
The extent and speed of these currents is evidenced by the extent and nature of the erosion, as well as by the gravel veneer deposited on top of the erosional surfaces. But the best way to visualize the energy involved is to understand that the shelf-slope system on the present continental margin was rapidly deposited from eroded Appalachian sediments.
|Continental margin off the northeastern United States.|
As the Floodwater transformed from sheet flow into channelized flow, the erosion became narrow and linear. Valleys, canyons, and water and wind gaps would then be cut until the Flood ended. This is similar to the two-step erosion on the Colorado Plateau: (1) the Great Denudation from sheet flow, and (2) the Grand Canyon, Zion Canyon, and other canyons from channelized flow (Oard, 2010, 2011a, also see the excerpted article Did Noah's Flood make the Grand Canyon?).
The Flood explanation also differentiates between wind and water gaps. Wind gaps represent early water gaps that were left high and dry as the water level rapidly dropped or the current velocity diminished quickly, leading to the cessation of erosion (Figure D). These would have remained as remnants at high elevations while the lowering water carved new gaps at lower elevations, establishing the basic post-Flood drainage patterns. Today, only wind traverses the higher gaps, while the rivers naturally take advantage of the low water course through the water gap established at the very end of the Flood.
Mainstream "millions of years" scientists oscillate back and forth between failed explanations for the formation of water gaps. But the Global Flood described in the book of Genesis leads to a very reasonable explanation.
The retreating waters started with sheet flow that would have been flowing perpendicular to ridges and ultimately deposited the continental shelves. The sheet currents initiated the water gaps by cutting narrow deep notch that channeled the water through. Most of the remainder of the mountain wall remained intact.
The sheet flow then diminished to channelized currents with anomalously high velocities and scale. They are the only feasible explanation for the phenomenon of aligned water gaps in a series of perpendicular ridges, as seen throughout the Appalachians. This ultra high energy channelized flow stopped so quickly that it left many water gaps high and dry. These resulted in the many wind gaps, unexplainable by any uniformitarian model involving millions of years.
Once again, a creationist explanation is the one that holds water.
Clark, G.M. 1989. Central and southern Appalachian water and wind gap origins: review and new data. Geomorphology 2:209–232.
Oard, M.J. 2010. The origin of Grand Canyon part IV: the great denudation. CRSQ 47:146–157.
Schumm, S., and F.G. Ethridge. 1994. Origin, evolution and morphology of fluvial valleys. In Dalrymple, R.W., R. Boyd, and B.A. Zaitlin (editors), Incised-Valley Systems: Origins and Sedimentary Sequences, pp. 11–27. SEPM Special Publication No. 51, Tulsa, OK.