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PDF VersionCopyright © 2008 by Creation Research Society. All rights reserved. Winter
2008, Water Gaps in the Alaska Range Michael J. Oard* Abstract Two of the six water gaps through the
Alaska Range will be briefly described. These water gaps fit in
with a worldwide pattern of well over one thousand water gaps. Water gaps are
a major mystery to uniformitarian geology. The three main uniformitarian
hypotheses for the origin of water gaps will be analyzed and found wanting.
There does not appear to be any evidence for either of the two hypotheses
suggested for the origin of the Alaska Range water gaps. However, the Flood
paradigm successfully explains these water gaps, as well as practically all
others, and even wind gaps. Both wind and water gaps could have been rapidly
carved during the Channelized Flow Phase of the Flood, when strong water
currents were flowing perpendicular to mountains or ridges. An analog for
a water and wind gap occurred during the gigantic Lake Missoula flood at
the peak of the Ice Age. Introduction Water gaps are another of the
many uniformitarian mysteries of geomorphology (Oard, 2008), which is the
study of the features of the earth’s surface. Present processes over millions
of years are invoked to explain these water gaps, and several hypotheses have
been invented. Not only is it difficult to prove them; there is also
evidence against them. This paper will describe the Alaska Range water gaps,
especially the more assessable Nenana and Delta water gaps, and relate them to
water gaps found worldwide. It will be shown that the Genesis Flood provides a
reasonable mechanism for their formation. A water
gap is: “A deep pass in a mountain ridge, through which a stream flows;
esp. a narrow gorge or ravine cut through resistant rocks by an antecedent
stream” (Bates and Jackson, 1984, p. 559). In other words, a water gap is a
perpendicular cut through a mountain range, ridge or other structural barrier.
This definition of a water gap unfortunately includes the mechanism of an
“antecedent stream,” which is: “A stream that was established before local
uplift began and incised its channel at the same rate the land was rising; a
stream that existed prior to the present topography” (Bates and Jackson, 1984,
p. 22). This is the case of a hypothesis intruding on observations: the definition
presupposes that water gaps are created by streams that eroded down precisely
at the same rate as tectonic uplift. A definition of a geological
feature should be purely descriptive without
speculation concerning its origin. Furthermore, a search of the literature
demonstrates that uniformitarian scientists claim five possible mechanisms for the
formation of water gaps, only one of which is an antecedent stream or
river. Wind
gaps are related to water gaps, but are not eroded deeply enough to sustain
present day water flow (Figure 1). A wind gap is: “A shallow notch in the
crest or upper part of a mountain ridge, usually at a higher level than a water
gap” (Bates and Jackson, 1984, p. 559). The notch in a ridge has to be an erosional notch, not a notch caused by
faulting or some other mechanism. In other words, the entire ridge was once
near the same altitude, until a notch was eroded across its top. A wind gap is
considered an ancient or incipient water gap, thought to have formed either
when the sediments were thicker in the surrounding valleys or before the ridge
had uplifted, if the ridge is a fault block. Uniformitarian geologists believe
that wind gaps were initially cut by a stream or river. Then following either
valley erosion or mountain uplift, the stream flowing through the ancient
water gap was diverted and its course through the ridge abandoned. So, the wind
gap was left at a higher altitude than the adjacent valley, which is why no
stream or river flows through it today. Only wind passes through the gap
now, which is why it is called a wind
gap. The Alaska Range Water Gaps The Alaska Range (Figure 2) is
an arc-shaped, generally east-west mountain range 600 miles (965 km) long in
southern Alaska. It merges with the Wrangell and St. Elias Mountains on the
east and the Aleutian Range on the west (Wahrhaftig, 1958). The highest
mountain in North America, Denali (formerly Mount McKinley) at 20,135 ft (6,194
m), lies within the western Alaska Range. Most mountains are much lower with
the crest of most of the range averaging between 7,000 and 9,000 ft (2,135 and
2,745 m) high. The lowlands north and south of the range are at low altitudes.
The Tanana Basin to the north is a broad, swampy lowland with average elevation
between 395 to 820 ft (120 and 250 m) asl (Bemis, 2004). Six
rivers rise in the lowlands south of the
range and flow northward across the range in water gaps to empty into the
Yukon or Tanana River (Thornbury, 1965). These rivers are located at
semi-regular intervals of 25 to 100 miles (40 to 160 km) apart (Wahrhaftig,
1965), and from west to east they are the Nenana, Delta, Nabesna, Chusana,
Beaver, and White Rivers. The northwest foothills are a series of parallel
east-west ridges, caused by folding and thrusting, and separated by long narrow
valleys (Bemis, 2004). Just as mysterious, the drainage is even perpendicular
to these ridges and valleys: Strangely
enough, the drainage does not follow these valleys but has a dendritic pattern
roughly at right angles thereto, the rivers cutting directly across ridges and
valleys alike (Wahrhaftig, 1958, p. 52). In fact,
the drainage of the rivers and tributaries is remarkably straight and parallel
through these ridges (Wahrhaftig and Black, 1958). The origin of this drainage
pattern is a puzzle. The
Nenana River is the first water gap to the west (Figure 3 and 4). The
main highway (George Parks Highway or Highway 3) from Anchorage to Fairbanks
passes through this water gap, which is only 2,363 ft (720 m) asl. The next
water gap to the east is the water gap of the Delta River in which the Richardson
Highway (Highway 4) and the Trans-Alaska pipeline pass through (Figures 5 and
6). Both water gaps pass through a generally low area in the Alaska Range. How
did such water gaps form? Water Gaps Worldwide One would think that such
transverse drainage through a mountain range would be rare, but it is not.
Water gaps are found worldwide. For instance, there are numerous water gaps,
small and large in the western United States. In
numerous places, especially in the Southern and Middle Rockies, rivers cut
across uplifts cored by resistant rocks in preference to what appear to be more
logical courses on softer rocks around the uplifts (Madole et al., 1987, p.
213). The
Grand Canyon is a one-mile-deep (1.6 km) water gap. The Colorado River flows
through several plateaus, the highest of which is the Kaibab Plateau, more than
9,000 ft (2,745 m) high. The origin of this water gap has been an enigma for a
long time. Both uniformitarians and creationists have struggled to explain its
origin (Young and Spamer, 2001). The uniformitarian hypotheses seem hopelessly
muddled. There
are 300 water gaps in the Zagros Mountains of western Iran alone, creating
gorges up to 8,000 ft (2,440 m) deep (Oberlander, 1965). These mountains rise
up to 15,000 ft (4,575 m) above sea level, and are 1,000 miles (1,600 km) long
and about 150 miles (240 km) wide. The Zagros Mountains are “very young”
geologically (Pliocene) and little modified by erosion, which means that
the water gaps are even “younger.” The lower walls of some water gaps are near
vertical, sometimes overhanging. The most impressive aspect of the Zagros
drainage is that the streams and rivers appear to shun valleys and prefer to transect mountains—numerous times. The
Zagros drainage pattern is distinctive by virtue of its disregard of major
geological obstructions, both on a general scale and in detail…Certain streams
ignore structure completely; some appear to “seek” obstacles to transect; others
are deflected by barriers only to breach them at some point near their
termini. Many streams cut in and out of anticlines without transecting them
completely, and a few cross the same barrier more than once in reverse
direction (Oberlander, 1965, pp. 1,
89, quotes his). There
are probably well over 1,000 water gaps across the earth. Since
these early studies [in the late 19th century]
transverse drainage has [sic] been identified from most major mountain
belt regions around the world… (Stokes and Mather, 2003, p. 61). So, the Alaska Range water gaps
are not unusual, but part of a common worldwide pattern. Water Gaps— The origin of water gaps is
mysterious within the uniformitarian paradigm (Oard, 2001; 2007; 2008).
Crickmay (1974) noted that rivers seem to cut water gaps as if there were no
mountain barrier. Admittedly
a fascinating picture, a river runs over low, open plains directly towards
seemingly impassable mountains but, undiverted by their presence, passes
through them by way of a narrow defile, or water gap, to a lower region
beyond. (p. 154.) How
could this have happened? Summerfield (1991) states that such discordant
drainage is especially common in fold mountains. One of
the most perplexing problems of drainage development to unravel is that
provided by transverse drainage. Such a
drainage pattern, which is also known as discordant
drainage,
occurs when river channels cut across geological structures … Such drainage,
which is common in fold mountain belts, is often regarded as anomalous,
although this is not really an appropriate description. (p. 411, emphasis in
original.) Why
should a river or stream flow through a barrier and not pass around it?
Like canyons, uniformitarians assume a river erosion origin simply because a
river is presently flowing through the gap. They ignore the possibility
that some other mechanism could have cut the gap first and then the river
simply followed the easiest route afterwards. Their reasoning is compromised by
their commitment to uniformitarianism (or actualism), and their ideas, though
plentiful, are poorly supported by observation, as will be shown below. It is
important to realize that not all water gaps are mysterious. Water gaps are
only a puzzle when the river or stream could have more easily flowed
around the ridge or mountain, but instead ended up cutting through the barrier.
For example, the Columbia River Gorge between Oregon and Washington is a major
water gap through the Cascade Mountains, but it runs through one of the lowest
paths through the Cascade Mountains. Presumably when the mountains were lower
and/or the rocks in eastern Washington and Oregon higher, the drainage would
have already been established. Despite Hypotheses, Origin of Water
Gaps Unknown Although there are five
hypotheses for the origin of water gaps, only three are considered significant:
1) the antecedent stream model, 2) the superimposed stream model, and 3)
stream piracy (Austin, 1994; Stokes and Mather, 2003; Williams et al., 1991;
1992). The Antecedent Stream Hypothesis The antecedent stream hypothesis
requires a river to be flowing in a set course prior to uplift of a
landscape of low relief. Then a barrier, such as a mountain range, is uplifted
in the path of the stream, but the process is sufficiently “slow” so that
the stream or river maintains its course by eroding the landscape as it rises
(Figure 7). The antecedent stream hypothesis was probably the first
hypothesis invoked to explain transverse drainage. John Wesley Powell assumed
that antecedent streams had cut the Green River and Grand Canyon water gaps.
Most geologists accepted Powell’s hypothesis for many years. This
theory applies mainly to large rivers because only they have enough erosive
power to keep up with uplift (Ahnert, 1998). However, some investigators
believe that any river erosion would be too slow relative to mountain building
to cut valleys, and do not accept the model. Although Twidale (1976) disagreed
with that assessment, he did admit that antecedent rivers or streams are
rare. In many
cases, the antecedent stream hypothesis can be ruled out for a number of
reasons. For instance, the water gaps in Wales are cut through “old” mountains
(Small, 1978). The rivers would have to be even older, which seems impossible.
So, the Wales water gaps are assumed to have originated by superimposition,
since there is no other viable hypothesis. In order
to demonstrate antecedence, one must usually prove that the river in question
predates uplift—a very difficult task (Twidale, 1976). Then, uplift must
be slow enough not to deflect the river’s course (Ranney, 2005). This
special conjunction of time and erosion would be unusual, especially over a
long period of time. If the river is flowing through an enclosed basin
and the mountains rise too fast, a lake should form upstream of the barrier,
but lake deposits are rarely if ever found. The chance of creating one water
gap is low; creating multiple aligned gaps seems astronomical. The antecedent
stream hypothesis appears to be a very simplistic explanation with little or no
evidence. Sometimes, this idea is put forward simply because any other
alternative is even more improbable (Small, 1978). Geologists
have recognized this, and many “antecedent stream” water gaps have been
“reinterpreted,” suggesting that there was little or no evidence for
antecedence in the first place. For instance, the water gaps on the
Laramie, Arkansas, North Platte, and South Platte Rivers in the east central
Rockies, once attributed to antecedent streams, are now considered products of
superimposed streams (Short and Blair, 1986). Twidale (2004, p. 193) noted the
difficulty of demonstrating the possibility of the antecedence
hypothesis. It is
fair to state that though many rivers of tectonically active regions are probably
of such an origin [antecedence], but like warping in relation to river capture,
it is difficult to prove. The ages of the river and of the implied
tectonism have to be established, and this is rarely possible. Thus,
the antecedent stream hypothesis faces these difficulties: • It is
now considered a minor contributor to water gaps •
Streams must predate uplift •
Geologists must prove that the mountains were uplifted, instead as a result of
erosion • Uplift
must have been slow enough not to deflect the stream’s original course •
General absence of expected upstream lake deposits •
Hypothesis has been rejected in many cases upon further study •
Aligned water gaps cannot be explained The Superimposed Stream Hypothesis Problems in the antecedent
stream model led to the superimposed (sometimes referred to as superposed) stream hypothesis. But, this
model seems to have just as many problems. A superimposed stream or river is
defined as: “A stream that was established on a new surface and that
maintained its course despite different lithologies and structures encountered
as it eroded downward into the underlying rock” (Bates and Jackson, 1984). In
this hypothesis, a landscape is buried by renewed sedimentation, usually
caused by marine transgression. Then, a stream or river is established on the
generally flat cover of sediments or sedimentary rock, called the
“covermass.” As erosion takes place over millions of years, the stream erodes downward,
maintaining its course even upon encountering harder rock beneath the
covermass. So, after millions of years the stream ends up flowing through
the older structural barriers. At the same time, the rest of the cover mass is
eroded, leaving behind a river flowing through ridges or mountains
(Figure 8). Apparently, any evidence of a prior “covermass” is enough to
convince geomorphologists of this hypothesis (Twidale, 2004). Although
geologists at first believed that the Rocky Mountain water gaps were
caused by antecedent streams, they later embraced the superimposed stream
hypothesis. But Hunt (1967) was skeptical: However,
the stream courses across the various ranges in the Rocky Mountains probably
are not superimposed. Too much fill would have been required to bury the
several mountain ranges, and too much erosion would have been required to
remove that fill. (p. 272.) There is
rarely any evidence for such a thick covermass or its deposition by a prior
transgression. A major
problem with superimposition is that the river must maintain the same course
to cut into resistant formations, while at the same time meander enough to
erode the covermass, leaving only the more resistant rocks at higher elevations
(Crickmay, 1974, p. 155). Even if there was any evidence, the concept defies
logic. Consequently, there is rarely any evidence that water and wind gaps
formed from superposed streams: Although
a plausible mechanism, superimposition is extremely difficult to verify
except in the case of very young orogens [uplifted linear, folded, and deformed
mountain belts] where vestiges of the original sedimentary cover remain. In ancient
mountain belts, denudation will have removed all the evidence of any
pre-existing sedimentary cover (Summerfield, 1991, p. 411, brackets
added). Even
when erosional remnants of sediments are found, they do not automatically
imply continuous coverage above the existing terrain. Since most of the strata
have been eroded, it is in fact an argument from a lack of evidence, and
therefore weak. Thus, the
superimposed stream hypothesis faces these difficulties: •
Absence of evidence for hypothetical transgressions and resulting covermass • Rivers
erode downward to cut structure, but covermass is eroded laterally •
Absence of evidence •
Erosional remnants do not prove original covermass •
Geometry demands incredibly large covermass in some cases • Stream
should be deflected and eroded downward from hard sediments into
underlying and adjacent soft rock The Stream Piracy Hypothesis The third major hypothesis is
called stream piracy or stream capture (Figure 9). Summerfield
(1991, p. 410) explained: “River capture occurs when one stream erodes more
aggressively than an adjacent stream and captures its discharge by
intersecting its channel.” The higher rate of erosion by the capturing stream
can be attributed to: (1) a steeper gradient, (2) greater discharge, (3) less
resistant rocks, and (4) higher precipitation. Several
lines of evidence are offered for this model (Small, 1978). One is the “elbow
of capture,” which is a sharp change in channel direction on the order of 90°
or more. Another is a “misfit” stream—one which carries too much water or
too little for its channel. Underfit streams, where flow is too
small, are common. Overfit streams are those where flow is too
large for the channel. Captured streams are underfit below the point of
capture, and the “pirate” stream becomes overfit past that point. Wind
gaps, or “cols,” are thought to be the abandoned portion of a stream captured
long ago, especially when they contain exotic gravels. The
model is also supported by sudden gradient increases in river profiles,
known as “knickpoints.” A waterfall is an extreme example of a knickpoint.
Geologists attribute the sudden change in slope to stream capture. At first
glance, these phenomena seem to support the model. But an “elbow of capture”
may be caused by geological factors such as faulting or changes in lithology.
Not all sharp changes, even those in front of water gaps, are always attributed
to capture, such as the Yar River on the Isle of Wight (Small, 1978). Likewise,
misfit streams have other explanations. First, there is little or no
evidence for overfit streams, which should be observed at any recent
capture event. Dury (1964) demonstrated that virtually all streams in an area, whether presumed captured or
not, are underfit. He considered this strong evidence against the capture
hypothesis. Cols can also form in other ways (Small, 1978). The best evidence
for flow through cols is the presence of exotic water-worn gravels. But
these gravels cannot show whether a stream was captured, diverted, or simply
dried up. Finally, knickpoints are also equivocal unless accompanied by other
evidence because they can be caused by renewed regional uplift or a “young” stream
that is still eroding headward. The
model seems simple enough given millions of years of denudation, yet reality is
more complex. Many supposed examples have ignited disputes among
geomorphologists (Small, 1978). If nothing else, the mechanism has been applied
too liberally (Small, 1978). The origin of the transverse drainage of the
Zambezi River in Africa was assumed to have been caused by river capture
(Thomas and Shaw, 1992), but it has since been proposed that this instance of
river capture was caused by a catastrophic flood from a breached
paleolake. In order
to demonstrate stream piracy, it must be shown that the pirating stream was
incised to a significantly lower level than its victim. But past erosional
levels are often erased by ongoing active erosion. Small
(1978) stated that there rarely is direct evidence for stream piracy; it is an
inference from general features: “It must be apparent from this discussion that
the phenomenon of river capture cannot be ‘taken on trust’ ” (p. 229). It seems
impossible for stream piracy to account for aligned water gaps observed in some
areas. Given the “bandwagon effect,” there may be many incorrect applications
of the model. Thus,
the stream piracy model faces these difficulties: • Other
explanations exist for the “elbow of capture,” wind gaps, and knickpoints • Overfit
streams are nearly nonexistent • Most
streams are underfit • It is
hard to demonstrate historically deeper erosion by the pirating stream •
Aligned water gaps cannot be explained • Evidence
is often missing Little, If Any, Evidence for
Uniformitarian Hypotheses In summary, there rarely is
evidence for any of
these uniformitarian hypotheses. One of them is simply invoked to provide some
explanation for wind or water gaps. Any of them is preferable to no hypothesis
at all. However, investigators rarely present compelling evidence. It is easy
to understand how the different hypotheses come and go for a particular area. Thomas
Oberlander probably has studied water gaps more rigorously than anyone else. He
has many sobering thoughts on past and present research. For instance,
Oberlander (1965) noted the conjectural nature of explanations. The
question of the origin of geological discordant drainage has almost always
been attacked deductively, leading
toward conclusions that remain largely within the realm of conjecture. Accordingly, the anomalous
stream courses are attributed to previous tectonic environment [antecedence],
to superposition from hypothetical erosion
surfaces or covermasses, or to headward extension under largely unspecified controls [stream piracy]. (p.
1, emphasis and brackets added.) Twenty
years later, Oberlander (1985) expressed the same opinion. Large
streams transverse to deformational structures are conspicuous geomorphic
elements in orogens [mountains] of all
ages.
Each such stream and each breached structure presents a geomorphic problem.
However, the apparent absence of empirical
evidence for
the origin of such drainage generally limits comment upon it…. Transverse
streams in areas of Cenozoic deformation are routinely attributed to stream
antecedence to structure; where older structures are involved the choice
includes antecedence, stream superposition from an unidentified covermass, or headward stream extension
in some unspecified manner
[piracy]. Whatever the choice, we are rarely provided
with conclusive supporting arguments. (pp. 155–156, brackets and emphasis
added.) Given that all uniformitarian
hypotheses are insufficient, we should wonder if the problem lies with
the parent paradigm of uniformitarianism.
The Hypotheses Applied to Some have suggested that the
water gaps through the Alaska Range and the northern foothills formed by
antecedent drainage—the Alaska Range was uplifted through existing rivers
which maintained their courses (Thornbury, 1965). The late Cenozoic uplift of
the Alaska Range, about 5 to 6 million years ago within the uniformitarian
timescale (Fitzgerald et al., 1995), could be considered evidence in favor of
antecedence. But, geologists believe the drainage was established after the
uplift. Without antecedence (stream piracy was not considered), Wahrhaftig
and Black (1958) defaulted to superimposed streams. In their model, the folds
and thrusts for at least the northern foothills first formed ridges, then
the whole area was covered with a flat “covermass,” and finally a
drainage superimposed on this covermass carved downward into the ridges.
Finally, the valleys were eroded. However, the streams and rivers are
unexpectedly parallel, which is surprising since they would have had to meander
extensively to erode the valleys (Wahrhaftig and Black, 1958; Wahrhaftig,
1965). The
water gaps of the Alaska Range are just as mysterious as the many other water gaps
across the Earth. None of the uniformitarian models fit the evidence.
Perhaps the answer is to explore outside the uniformitarian paradigm. The Late Flood Origin Uniformitarian hypotheses for
the formation of water and wind gaps are essentially speculative guesses with
little, if any, supporting evidence. There are numerous problems with all three
major hypotheses. A better explanation can be found by shifting paradigms and
examining how catastrophic erosion during the late Flood can explain these
features. Did Water Gaps Form Some creationists have suggested
that some water and wind gaps were cut by post-Flood erosion during local catastrophic
events, such as the dam-breach hypothesis for the origin of Grand Canyon
(Austin, 1994; Brown, 2001). However, I believe that the evidence supports a
late-Flood origin for these features. Erosion
from a catastrophic dam breach could create water and wind gaps. This has been
suggested as the cause of anomalous drainage on the Zambezi River (Thomas and
Shaw, 1992). The dam could have been rock or unconsolidated debris. In either
case, it evidently gave way, much like the failure at Red Rock Pass and
catastrophic flooding down the Snake River from Ice Age Lake Bonneville in the
Salt Lake basin in Utah (Oard, 2004a). The Bonneville flood is believed to have
discharged 1,150 mi3 (4,750 km3) of
water in eight weeks, dropping Lake Bonneville 354 ft (108 m) [O’Connor, 1993].
However, this flood did not appear to produce any water or wind gaps. The Ice
Age would have produced lakes dammed by ice sheets in North America, Europe,
and Asia. Several of these show evidence of breaching by overtopping a bounding
ridge, cutting a canyon and reversing the drainage of a river. Glacial Lake
Agassiz in south-central Canada spilled over ridges at many locations (Oard,
2004a) that may have become water or wind gaps.
One of
the largest ice age lakes was glacial Lake Missoula (Oard, 2004a). After this
lake deepened to 2,000 ft (610 m) at the ice dam in northern Idaho, the ice
burst, producing one of the largest floods since that of Genesis. Glacial
Lake Missoula contained 540 mi3 (2,210
km3) of water and emptied in two days, sending a wall of
water around 400 ft (120 m) deep across the Pacific Northwest, from Spokane,
Washington to Portland, Oregon. It did produce one impressive water and wind
gap, illustrating a mechanism for these features more plausible than any
uniformitarian model. Stream
capture is also feasible after the Flood, especially by small streams and in
areas where very little erosion would suffice to trigger capture. However,
given the relative difference in erosion rates during and since the Flood, one
would not expect significant stream piracy in the approximately 4,500
years since the Flood. During the post-Flood period, stream piracy should be
rare, and any water gaps would be small.
A Flood Mechanism If few water or wind gaps have
formed since the Flood, then they must have formed during the Flood. Since
these gaps appear to be among the final features formed in the geologic
sequence of events, they must have been cut late in the Retreating Stage of the
Flood. Uniformitarians recognize this relative timing and attribute water and
wind gaps predominantly to the late Cenozoic. For instance, the 300 water gaps
in the Zagros Mountains are believed to have been excavated during the late
Cenozoic (Oberlander, 1965). The
Recessive Stage of the Flood can be divided into an early Sheet Flow Phase and
a later Channelized Flow Phase (Walker, 1994). It is unlikely that any water
gaps formed during the Sheet Flow Phase, because the widths of water gaps are
much narrower than the sheetflow currents, which were probably very wide.
But it is possible that notches could have been initiated in a mountain barrier
or ridge by local variations in the sheetflow currents or by structural
or lithological zones of weakness. These would have been subsequently enlarged
during channelized flow. Regardless of when the initial notch developed,
the large majority of water gaps, as well as wind gaps, probably formed during
the Channelized Flow Phase. As the
currents became more laterally restricted, mountains and plateaus would have
been rising above the retreating Floodwater. Currents would have been diverted
into low areas or notches formed earlier. For a time, current velocities would
have remained high enough to form water and wind gaps, and even large canyons Rapid Cutting of Water Water and wind gaps, up to the
size of valleys and canyons would have been rapidly cut during the Channelized
Flow Phase. Because the base level for the recession of the Flood was the newly
created ocean basins, currents would have often flowed perpendicular to
mountains and hills, cutting through them instead of going around, forming
valleys, canyons, and pediments (Oard, 2004b; 2007) [Figure 10a]. The high
current velocity would have cut gaps directly through elevated topography. In
many cases, overlying sediments would have been eroded too, like an accelerated
version of the superimposed stream hypothesis. Because
these landscapes were created by a rapid hydraulic event, it is important to
consider current variations, even during the sheetflow runoff (Schumm
and Ethridge, 1994). These variations might have initiated notches at higher
elevations. Lithological or structural weaknesses could also have been
involved, although few water gaps are associated with faults. A fourth
possibility is that the channelized flow cut gaps from notch to completion.
Regardless, once formed, the currents would have sped up through the notch
relative to the surrounding flow (Figure 10b). Therefore, erosion would
have accelerated with the current velocity. Abrasive sediment in the water
would also have contributed to rapid erosion of the gaps (Figure 10). We can
see the same phenomena today when a dam breaches. Once the water finds
the point of failure, it rapidly cuts down, although parts of the dam may
survive intact. Wind
gaps are found at higher elevations than the local drainage. They might be
high because they were not cut to sufficient depth, either from a drop in
water level or decrease in erosional energy. They may also have been uplifted
too high. At any rate, they transport only wind today (Figure 10c,d). Dynamic
Flood processes could also account for some of the evidence attributed to
stream capture, such as the elbow of capture; rounded, exotic gravels in wind
gaps; and underfit streams. For example, an elbow of capture might have
formed by shifts in a channelized current as it cut into a valley first
in one direction, then another. Another
advantage of the Flood hypothesis is that it explains multiple, aligned gaps—a
singular point of failure for the uniformitarian theories. A high-velocity
Flood current would be flowing on a regional to megaregional scale. Thus,
its momentum would easily carry it though multiple barriers, and the large size
of the current would create aligned water or wind gaps in a series of perpendicular
ridges, such as those observed in the Appalachian Mountains of the eastern
United States and the MacDonnell Ranges in central Australia. A
further evidence of rapid, abrupt formation of gaps is the youthful appearance
of such features. They show little signs of later erosion. Crickmay (1933)
stated that wind gaps have been modified little by weathering since they
first formed. This is entirely consistent with the Flood explanation—the
Channelized Flow Phase was the last
event
of the Flood and occurred only a few thousand years ago. This “youthfulness” is
also an argument against the uniformitarian model; we would have to accept that
wind gaps have remained untouched by erosion for millions of years. The Example of the Geomorphological evidence for
the Recessive Stage of the Flood is strong (Oard, in press). Whereas
uniformitarian geologists have to invent speculative secondary hypotheses to
salvage their paradigm in the light of conflicting evidence, the Flood paradigm
does not need to invent secondary hypotheses, because the evidence is
consistent with the paradigm. Furthermore, the Lake Missoula flood
offers the Flood paradigm an example of how a well-substantiated catastrophic flood
at the peak of the Ice Age (Oard, 2004a) created a water and wind gap. The Lake
Missoula flood (also called the Spokane or the Bretz flood) demonstrates
that the catastrophic model works much better than any low-energy solution. Despite
its width of up to 100 miles (160 km), the Lake Missoula Flood possessed a
current velocity of up to 65 mph (100 kph). There likely was only one major flood
and possibly a few minor floods afterwards (Oard, 2003; 2004a)]. One
major pathway was the Cheney-Palouse scabland tract in the eastern part of the flood
path. The southern portion of this tract includes the upper portion of
Washtucna Coulee. Prior to the flood, the Palouse River rising from the
mountains of northern Idaho flowed westward through this coulee and then
into the Columbia River. The Snake River flows parallel to the Washtucna
Coulee about 10 miles (16 km) south. There is a basalt ridge covered by about
100 ft (30 m) of the Palouse silt between the Snake River and Washtucna Coulee.
This ridge is about 500 ft (150 m) above the Snake River. The Lake
Missoula flood rushed southward into the head of Washtucna Coulee. It
overtopped the ridge between Washtucna Coulee and the Snake River at two
locations, forming a water and wind gap (Figure 11). To the east, the width was
initially around 8 miles (13 km), but the flow eventually formed a
narrow, vertically walled canyon 500 ft (150 m) deep—down to the level of the
Snake River. The narrow erosion likely was manifested as a “retreating waterfall.”
After the flood, the Palouse River, instead of continuing its flow
westward down Washtucna Coulee as before, took a 90° left-hand turn and flowed
through what is now called Palouse Canyon and into the Snake River. Palouse
Canyon is therefore a water gap formed during the Lake Missoula flood.
Palouse Falls (Figure 12) would then represent a “knickpoint.” The Lake
Missoula flood also breached the ridge between Washtucna Coulee and the Snake
River 15 miles (24 km) west of Palouse Canyon. A narrow notch called Devils
Coulee, 500 ft (150 m) deep was eroded through the ridge. However, the Lake
Missoula flood did not erode this coulee deep enough at its entrance from
Washtucna Coulee. The entrance to Devils Coulee is approximately 100 ft (30 m)
above Washtucna Coulee, and no stream was diverted down Devils Coulee. So
Devils Coulee remains a wind gap. Palouse Canyon and Devils Coulee, therefore,
are examples of how large volumes of energetic floodwaters can rapidly
excavate water and wind gaps in hard rock (Oard, 2003). Summary Six water gaps cut through the
Alaska Range, as well as foothills north of the range. These features are
similar to well over 1,000 water gaps across the earth, 300 alone in the Zagros
Mountains of Iran. How a river could cut through a mountain range or ridge
presents a seemingly insurmountable challenge to uniformitarian geologists. It
does not seem that an appeal to actualism would help. Of course, many
hypotheses have been invented over the years—all with apparently fatal
problems. Water and wind gaps can rapidly be cut during the Channelized Flow
Phase of the Flood by currents flowing perpendicular to mountains and
ridges. An example of the cutting of a water and wind gap in a few days is
provided by the Lake Missoula flood. Worldwide water and wind gaps, like
other global geomorphological mysteries, point to a global Flood. Acknowledgments I thank Hank Giesecke for
accompanying me during this trip to view the Nenana and Delta River water gaps
in the Alaska Range. I also thank North Star Bible Camp of Willow, Alaska, for
their generous hospitality in providing housing, meals and wheels for this study.
I appreciate John Reed fine-tuning several of the figures. Finally, I
thank Bryan Miller of Master Books for drawing Figure 8. This
research was supported by a research grant from the Creation Research Society.
References CRSQ: Creation Research Society Quarterly Ahnert,
F. 1998. Introduction to Geomorphology. Arnold,
London, UK. Austin,
S.A. 1994. How was Grand Canyon eroded? In Austin, S.A. (editor). Grand Canyon: Monument to Catastrophe, pp.
83–110. Institute for Creation
Research, Santee, CA. Bates,
R.L. and J.A. Jackson (editors). 1984. Dictionary
of Geological Terms, 3rd edition, Anchor Press/Doubleday, Garden City, NY. Bemis,
S.P. 2004. Neotectonic Framework of the
North-Central Alaska Range Foothills. M.S. thesis, University of
Alaska Fairbanks, Fairbanks, AK. Bretz,
J.H., 1928. Alternative hypotheses for Channeled Scabland. I. Journal of Geology 36:193–223. Brown, W.
2001. In the Beginning: Compelling
Evidence for Creation and the Flood, 7th edition.
Center for Scientific Creation, Phoenix, AZ. Crickmay,
C.H. 1933. The later stages of the cycle of erosion: some weaknesses in the
theory of the cycle of erosion. Geological
Magazine
70:337–347. Crickmay,
C.H. 1974. The Work of the River: A Critical
Study of the Central Aspects of Geomorphology. American Elsevier
Publishing Co., New York, NY. Dury,
G.H. 1964. Principles of Underfit Streams—General Theory of Meandering
Valleys. U. S. Geological Survey Professional
Paper 452-A,
Washington, D.C. Fitzgerald,
P.G., R.B. Sorkhabi, T.F. Redfield, and E. Strump, 1995. Uplift and
denudation of the central Alaska Range: a case study in the use of apatite fission
track thermochronology to determine absolute uplift parameters. Journal of Geophysical Research
100(B10):20,175–20,191. Hunt,
C.B. 1967. Physiography of the United
States.
W.H. Freeman and Company, San Francisco, CA. Madole,
R.F., W.C. Bradley, D.S. Loewenherz, D.F. Ritter, N.W. Rutter, and C.E. Thorn.
1987. In Graf, W.L. (editors), 1987. Geomorphic
Systems of North America, Geological Society of America Centennial Special
Volume 2, pp. 211–257.Boulder, CO. Oard,
M.J. 2001. Vertical tectonics and the drainage of Floodwater: a model for the
middle and late diluvian period—Part II. CRSQ 38(2):82–83.
Oard,
M.J. 2003. Evidence for Only One Gigantic Lake Missoula Flood. In Ivey, R.L.
(editor). The Fifth International Conference
on Creationism,
technical symposium sessions, pp. 219–231. Creation Science Fellowship,
Pittsburgh, PA. Oard,
M.J. 2004a. The Missoula Flood Controversy
and the Genesis Flood. Creation Research Society Monograph No. 13, Chino
Valley, AZ. Oard,
M.J. 2004b. Pediments Formed by the Flood: Evidence for the Flood/post-Flood
Boundary in the Late Cenozoic. TJ
18(2):15–27. Oard,
M.J. 2007. Do Rivers Erode Through Mountains? Water Gaps are Strong Evidence
for the Genesis Flood. Creation
29(3):18–23. Oard,
M.J. 2008. Flood by Design: The Earth’s
Surface—Shaped by Receding Water. Master Books, Green Forest, AR (in press). Oberlander,
T.M. 1965. The Zagros Streams: A New
Interpretation of Transverse Drainage in an Orogenic Zone. Syracuse
Geographical Series No. 1, Syracuse, NY. Oberlander,
T.M. 1985. Origin of Drainage Transverse to Structures in Orogens. In Morisawa,
M. and J.T. Hack (editors). Tectonic
Geomorphology,
pp. 155–182. Allen and Unwin, Boston, MA. O’Connor,
J.E. 1993. Hydrology, Hydraulics, and
Geomorphology of the Bonneville Flood. Geological Society of America
Special Paper 274, Boulder, CO. Ranney,
W. 2005. Carving Grand Canyon: Evidence,
Theories, and Mystery. Grand Canyon Association, Grand Canyon, AZ. Rich,
J.L. 1933. Physiography and Structure at Cumberland Gap. GSA Bulletin 44:1,219–1,236. 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. Short,
N.M. and R.W. Blair, Jr. (editors). 1986. Geomorphology
from Space: A Global Overview of Regional Landforms. NASA,
Washington, D.C. Small,
R.J. 1978. The Study of Landforms: A
Textbook of Geomorphology, second edition. Cambridge University Press,
London. Stokes,
M. and A.E. Mather. 2003. Tectonic origin and evolution of a transverse drainage:
the Río Almanzora, Betic Cordillera, Southeast Spain. Geomorphology 50:61. Summerfield,
M.A. 1991. Global Geomorphology. Longman
Scientific & Technical, New York, NY. Thomas,
D.S.G. and P.A. Shaw. 1992. The Zambezi River: tectonics, climatic change and
drainage evolution—is there really evidence for a catastrophic flood? A
discussion. Palaeogeography, Palaeoclimatology,
Palaeoecology
91:175–178. Thornbury,
W.D. 1965. Regional Geomorphology of the
United States.
John Wiley & Sons, New York, NY. Twidale,
C.R. 1976. Analysis of Landforms. John
Wiley & Sons Australasia Pty Ltd, New York, NY. Twidale,
C.R. 2004. River patterns and their meaning. Earth-Science
Reviews
67:159–218. Wahrhaftig,
C. 1958. The Alaska Range. In Williams H. (editor). Landscapes of Alaska: Their Geological Evolution.
University of California Press, Los Angeles, CA. Wahrhaftig,
C. 1965. Physiographic divisions of Alaska. U.S.
Geological Survey Professional Paper 482, Washington D.C. Wahrhaftig,
C. and R.F. Black. 1958. Quaternary and engineering geology in the central
part of the Alaska Range. U.S. Geological Survey
Professional Paper 293, Washington D.C. Walker,
T. 1994. A Biblical geological model. In Walsh, R.E. (editor). Proceedings of the Third International Conference on
Creationism,
technical symposium sessions. Creation Science Fellowship, pp. 581–592.
Pittsburgh, PA. Williams,
E.L., J.R. Meyer, and G.W. Wolfrom, 1991. Erosion of Grand Canyon Part
I—Review of antecedent river hypothesis and the postulation of large quantities
of rapidly flowing water as the primary agent of erosion. CRSQ 28:92–98. Williams,
E.L., J.R. Meyer, and G.W. Wolfrom. 1992. Erosion of Grand Canyon Part II—Review
of river capture, piping and ancestral river hypotheses and the possible
formation of vast lakes. CRSQ
28:138–145. Young,
R.A. and E.E. Spamer (editors). 2001. Colorado
River Origin and Evolution: Proceedings of a Symposium held at Grand Canyon
National Park in June, 2000. Grand Canyon Association, Grand Canyon, AZ. * Michael
J. Oard, 34 W. Clara Court, Bozeman, MT 59718, mikeoard@bridgeband.com Accepted
for publication: May 7, 2007 Figure
1. Cumberland Wind Gap in the Appalachian Mountains along the Virginia/
Kentucky border near Middlesboro, Kentucky (view northwest from highway 58).
This notch has been eroded down nearly 1,000 feet (300 m), as measured on the
northeast side (Rich, 1933). Figure
2. Shaded relief map of Alaska. The Alaska Range (arrow) is the arc-shaped
mountain range that extends from southwest Cook inlet to near the Alaska-Canadian
border. (From U. S. Geological Survey.) above:
Figure 3. The Nenana water gap
through the Alaska Range, view north, which is the same direction the river flows
(permission from Google EarthTM mapping
service). right:
Figure 4. Nenana water gap (view
north) from Denali Highway just southwest of Cantwell, Alaska. Figure
5. Delta River water gap through the Alaska Range, view north northwest, which
is the direction of river flow (permission from Google EarthTM mapping service). Figure
6. Delta River water gap (view north from Black Rapid Viewpoint). Figure
7. Block diagram showing the antecedent stream hypothesis. The stream is first
established. Then the ridge slowly uplifts while the stream is able to erode
through the barrier. Figure
8. Block diagram of the superimposed stream hypothesis. The stream maintains
its same course as most of the covermass (top layer) is eroded. (Illustration
drawn by Bryan Miller.) Figure
9. Block diagram of two stages of stream capture. (a) The stream on the lower
right is rapidly eroding headward and captures the right portion of the other
stream in (b). Modified from Summerfield (1991, p. 411). Figure
10. Series of schematics on the formation of water and wind gaps (drawn by
Peter Klevberg). (A) Water flowing perpendicular to a transverse ridge
forms shallow notches on the ridge. (B) Notches are eroded further as the water
level drops below the top of the ridge. (C) Floodwaters continue to drain as
notches deepen. (D) Floodwaters are completely drained with a river running
through the lowest notch, the water gap. Insufficient erosion in the
other notch left a wind gap. Figure
11. Map of ridge between Washtucna Coulee and the Snake River showing Palouse
and Devils Canyons cut from the Lake Missoula flood. Modified from
Bretz (1928, p. 205). (Drawing by Mark Wolfe.) Figure
12. Palouse Falls on the Palouse River between Washtucna Coulee and the Snake
River.
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