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Scabland; Scientific Bias Against Catastrophism by Chris
Evidence of the Flood in Franklin County
by Gerald Durr
Field Trip Help
Lake Missoula Flood
Michael J. Oard
Originally Published by Answers
Journal of Creation, 14(2):14-17, 2000
The Lake Missoula Flood was one of the largest floods
in earth history, the Genesis Flood being the largest, by far. The Lake
Missoula Flood, which also has been referred to as the Spokane Flood or
the Bretz Flood. Analyzing such a huge local flood may help us to
comprehend the awesome power of the Genesis Flood.
The Lake Missoula Flood occurred at the peak of the
Ice Age when a proglacial lake1 in the valleys of western
Montana, USA, broke through its ice dam and drained in about 48 hours
(Figure 1).2–5 It rushed through eastern Washington and down
the current path of the Columbia River at up to 35 m/sec with a discharge
about 15 times the combined flow of all the rivers of the world.6,7
Figure 1. The Lake Missoula Flood occurred when
Glacial Lake Missoula in northwest Montana broke through its
ice dam in northern Idaho and drained down the Columbia River. The Lake
Missoula Flood and other melting pulses from the Cordilleran Ice Sheet to the north swept a large area of Washington (after Waitt).22
Glacial Lake Missoula had a volume of about 2,200 km3
based on the many shorelines observed in the western mountain valleys of
Montana (Figure 2). It was ponded behind an ice dam at least 700 m thick
against a lobe of the Cordilleran Ice Sheet that occupied northern Idaho.
The Lake Missoula Flood is believed by some geologists to have carved out
the Grand Coulee and Dry Falls in north central Washington.8
The Grand Coulee is a gorge about 80 km long and up to 300 m deep. Dry
Falls sits at the head of a gorge about 100 m deep and 5 km long about
midway in the Grand Coulee.
Figure 2. Multiple shorelines of ancient Glacial
Lake Missoula are emphasized by horizontal shadows high up the side of Mt
The concept of the Lake Missoula Flood has had a
controversial history. Based on geological observations back in 1923, J.
Harlen Bretz postulated a gigantic flood in eastern Washington from an
unknown source.9,10 This started a storm of controversy that
lasted about 40 years. The idea of the Lake Missoula Flood was rejected
because it seemed too close to the biblical Flood. Victor Baker states:
‘Bretz’ flood theory was so despicable that even
circular reasoning could be employed to erect an alternative
hypothesis. … One cannot but be amazed at the spectacle of otherwise
objective scientists twisting hypotheses to give a uniformitarian
explanation to the Channeled Scabland. Undoubtedly these men thought
they were upholding the very framework of geology as it had been
established in the writings of Hutton, Lyell, and Agassiz.’
Creationists should not be surprised if uniformitarian
geologists see no evidence for the Genesis Flood.
Multiple flood explanations
Bretz’ ‘outrageous hypothesis’ was vindicated in
the 1960s when more than just a few geologists actually examined the area.
The evidence was obvious and overwhelming. Nevertheless, not just
content with one gigantic flood, uniformitarian geologists could not help
but postulate more than one. The Lake Missoula floods then became
The tradition started with Bretz himself, who at age 70
returned for fieldwork in eastern Washington, and postulated possibly up
to seven floods.12 Up until 1980, most investigators postulated
one or a few floods. In that year, Richard Waitt proposed a succession of
about forty Lake Missoula floods.13 His evidence was primarily
based on a series of about 40 rhythmites in Burlingame Canyon within the
Walla Walla Valley of southeast Washington (Figure 3). This valley is
located in a backwater basin that was inundated after the flood water
ponded behind a constriction at Wallula Gap, forming a lake about 250 m
deep. Waitt postulated that each rhythmite was laid down by one Lake
Missoula flood. He based his conclusion especially on the existence of a
supposedly subaerial ash layer on top of the thirteenth rhythmite from the
Figure 3. Spectacular rhythmites in Burlingame
Canyon within the Walla Walla Valley formed in a backwater basin that was
inundated when floodwater temporarily ponded behind Wallula Gap.
In 1986, the number of floods jumped to about 90, based
on 89 rhythmites separated by what are believed to be varves, which were
discovered in Sanpoil Valley in northeast Washington.14 Each
rhythmite was related to one Lake Missoula flood. A total of 3,000 varves
were claimed, intermingled within the flood rhythmites. So the whole
sequence of about 90 Lake Missoula floods was thought to have occupied a
period of 3,000 years. This is more than ten times too much time for the
deglacial phase of the post-Flood Ice Age, based on melting equations over
snow and ice during a cooler ice age climate.15
Only one flood
Lately, more geologists are swinging full circle back
to fewer, or even one, Lake Missoula Flood. Gary Smith disputed some of
the evidence used to argue that each rhythmite was a separate Lake
Missoula flood.16 Instead, he claimed that 2 to 9 rhythmites
make up each flood for a total of about 20 Lake Missoula floods, which
rather confuses the matter, especially since at any one location each
rhythmite is similar. Recently, a team of eight investigators from the
University of Alberta in Edmonton have re-evaluated the field evidence for
the number of floods and have concluded that there was only one
flood from glacial Lake Missoula, although they postulate that other
floods from British Columbia carved the Grand Coulee.17 The
latter postulate has some merit and needs to be evaluated further.
Shaw et al.18 argue that the volcanic
ash layer in the Burlingame Canyon was deposited underwater because
the ash layer was intercalated with silt and sand layers, which suggests
the simultaneous deposition of both the ash and suspension deposits. This
is a conclusion I arrived at when I examined the deposits, including the
ash layer (Figure 4).
Figure 4. Ash layers (light colour) in rhythmites
at Mabton in the Yakima Valley, indicate underwater deposition. The ash
layers are intercalated with silt and sand layers (two ash layers on right
thin to one layer on left) and display soft sediment deformation features.
Shaw et al. provide further evidence at
Burlingame Canyon and elsewhere along the flood path for just one gigantic
flood. First, the rhythmites fine upwards from 2 m thick to about 10 cm
thick, more indicative of one flood that waned with time. Second, minor
scours (maximum depth 80 cm) are confined to the basal units. If each
rhythmite were a separate flood, the scours should be all through the
rhythmites. Third, unique clastic dikes, which look like sand and silt
rhythmites, are cut through numerous beds and sometimes through the whole
sequence. This indicates that the dikes were formed under pressure
temporarily in excess of lithostatic pressure, and that most have formed after deposition of the entire sequence. Otherwise each bed would
have its own set of dikes, generally separated from other rhythmites. Shaw
et al. postulate that the rapid draining of the ponded lake, while
the groundwater head at depth in the sediments remained high, caused
explosive release of water that formed the clastic dikes.
And finally, the 89 rhythmites in northeast Washington
could not have been deposited by multiple Lake Missoula floods as
postulated by Atwater14 because they do not contain any basalt
clasts. Floodwater from a Lake Missoula flood would have had to traverse
the northern edge of the Columbia River Basalts and would have carried
abundant basalt clasts if they flowed north up the Sanpoil Valley. Since
basalt clasts are not present, the rhythmites in Sanpoil Valley were
clearly deposited by water flowing south, rather than north. Thus, the 89
rhythmites were not formed by multiple Lake Missoula floods, but most
likely by melting pulses from the Cordilleran Ice Sheet to the north.
Rhythmites deposited rapidly
A recent observation of a catastrophic outburst flood
(jökulhlaup) in Iceland provides further support for only one gigantic
Lake Missoula Flood.19,20 Water from snow, melted by a
subglacial volcanic eruption, burst from under the ice on November 5,
1996. The peak discharge was 45,000 m3/sec, which was only 0.2
% of the peak discharge of the Lake Missoula Flood. Iceland’s jökulhlaup
lasted about 36 hours. During the later half of the flood, the water
switched outlets causing the original outlet to act as a ‘slackwater
embayment’. Besides crossbeds in the slackwater embayment, planar
beds dipping at a low angle formed many normally graded rhythmites of fine
gravel and coarse sand. Two hundred planar rhythmites and 100 prograding
rhythmites formed a section 15 m thick in just 17 hours. That is one
rhythmite every 3 to 4 minutes! Moreover, large rip-up clasts of bedded
strata composed of stratified sand and gravel up to 3 m in diameter were
emplaced within the rhythmites. I have observed rip-up clasts in a number
of Lake Missoula Flood bars and slackwater deposits. Matrix-supported
outsized clasts within the rhythmites are reminiscent of ‘dropstone
varvites’ in claimed ancient ice age deposits.21
If the small Iceland flood can produce 15 m of
rhythmites in a short time, the Lake Missoula Flood can certainly form
rhythmites along the edge of its flow path with a maximum thickness at
Burlingame Canyon of about 50 m. Baker and others had postulated that the
rhythmites in the Lake Missoula Flood had been formed by multiple pulses
or surges up slack water valleys within a single flood. Each surge spread
a turbidity current-like deposit upvalley. The surges would be caused by
the uneven discharge from multiple valleys being drained in western
Montana and the multiple flood paths in eastern Washington that diverge
and converge. The rhythmites in Iceland were deposited by repeated
turbulent flow pulses, which supports the multiple rhythmite per
flood conclusion of Shaw et al.17
The Lake Missoula Flood, as well as the much smaller
Icelandic flood, may provide insight into the global Genesis Flood. For
instance, landforms produced by the Lake Missoula Flood may provide an
analogue for landforms produced by the Genesis Flood. We must be careful
of the scale problem, however. Secondly, the rhythmites of the Icelandic
and Lake Missoula Floods may provide insight on how turbulent flow pulses
can lay down sedimentary layers rapidly. Third, the rapid erosion of
approximately 200 km3 of loess and basalt from just one Lake
Missoula Flood can help us better appreciate the catastrophic erosional
processes of the Genesis Flood. These considerations need further
I thank Harold Coffin for sending me the article by
Shaw et al. from Geology. I also appreciate the co-operation
and encouragement of the Design Science Association of Portland, Oregon,
for many field trips within the former path of the Lake Missoula Flood.
1. A lake immediately in front of a glacier, or just
outside the limits of an ice sheet.
2. Baker, V.R., Paleohydrology and sedimentology of
Lake Missoula flooding in Eastern Washington, Geological Society of
America Special Paper 144, Boulder, Colorado, 1973.
3. Baker, V.R. and Nummedal, D. (eds), The
Channeled Scabland, National Aeronautics and Space Administration,
Washington, D.C., 1978.
4. Baker, V.R. and Bunker, R.C., Cataclysmic late
Pleistocene flooding from glacial Lake Missoula: a review,
Quarternary Science Reviews 4:1–41, 1985.
5. Benito, G., Energy expenditure and geomorphic work
of the cataclysmic Missoula flooding in the Columbia River Gorge, USA,
Earth Surface Processes and Landforms 22:457–472, 1997.
6. Allen, J.E. and Burns, M., with Sargent, S.C.,
Cataclysms on the Columbia, Timber Press, Portland, Oregon, 1986.
7. O’Connor, J.E. and Baker, V.R., Magnitudes and
implications of peak discharges from glacial Lake Missoula,
Geological Society of America Bulletin 104:267–279, 1992.
8. Weis, P.L. and Newman, W.L., The Channeled
Scablands of Eastern Washington — The Geologic Story of the Spokane
Flood, 2nd Ed., Eastern Washington University Press, Cheney,
9. Bretz, J.H., Glacial drainage on the Columbia
Plateau, Geological Society of America Bulletin 34:573–608,
10. Bretz, J.H., The Channeled Scablands of the
Columbia Plateau, J. Geology 31:617–649, 1923.
11. Baker, V.R., The Spokane Flood controversy; in:
Baker, V.R. and Nummedal, D. (eds), The Channeled Scabland,
National Aeronautics and Space Administration, Washington, D.C., pp.
12. Bretz, J.H., Smith, H.T.U. and Neff, G.E.,
Channeled Scabland of Washington: new data and interpretations,
Geological Society of America Bulletin 67:957–1049, 1956.
13. Waitt Jr, R.B., About forty last-glacial Lake
Missoula jökulhlaups through southern Washington, Journal of Geology 88:653–679, 1980.
14. Atwater, B.F., Pleistocene glacial-lake
depostis of the Sanpoil River Valley, northeastern Washington, U.S.
Geological Survey Bulletin 1661, Washington D.C., 1986.
15. Oard, M.J., An Ice Age Caused by the Genesis
Flood, Institute for Creation Research, El Cajon, California, 1990.
16. Smith, G.A., Missoula flood dynamics and
magnitudes inferred from sedimentology of slack-water deposits on the
Columbia Plateau, Washington, Geological Society of America Bulletin 105:77–100, 1993.
17. Shaw, J., Munro-Stasiuk, M., Sawyer, B., Beaney,
C., Lesemann, J.-E., Musacchio, A., Rains, B. and Young, R.R., The
Channeled Scabland: back to Bretz? Geology 27(7):605–608,
18. Shaw et al., Ref. 17, p. 607.
19. Russell, A.J. and Knudsen, O, An ice-contact
rhythmite (turbidite) succession deposited during the November 1996
catastrophic outburst flood (jökulhlaup), Skeidarárjökull, Iceland,
Sedimentary Geology 127:1–10, 1999.
20. Snelling, A.A., Iceland’s recent ‘mega-flood’: an
illustration of the power of Noah’s Flood, Creation, 21(3):46-48,
21. Oard, M.J., Ancient Ice Ages or Gigantic
Submarine Landslides? Creation Research Society Monograph 6, Chino
Valley, Arizona, pp. 57–67, 1997.
22. Waitt Jr, W.B., Case for periodic, colossal
jökulhlaups from Pleistocene glacial Lake Missoula, Geological Soc.
of America Bulletin, 96, p. 1272, 1985.