The cave connection of this second item from the "Windy City
Speleonews" is just J Harlen Bretz. Yes, no period after the J, which
was his full name. I had lunch with him when he was 94 at his house,
Boulderstrewn, in Homewood, Illinois. I happened to drive by, on the
way to the NSS convention in Bellingham, Washington, a few years ago,
the Dry Falls three miles wide, where the state of Washington has a
picnic area and displays. One non-technical source on the falls is http://www.gonorthwest.com/Washington/northeast/Dry_Falls.htm
, although links onward from that page are broken. -- Mixon
Cavers know J Harlen Bretz mainly as the author of "Caves of
Missouri" and coauthor of "Caves of Illinois," which was published
when he was 78 years old. To speleologists, he is best known for his
famous 1942 "Journal of Geology" paper on vadose and phreatic features
of caves. But his geological studies were by no means restricted to
caves, and he is probably best known for (and is most proud of) of
series of papers published between 1923 and 1932 in which he described
the very peculiar geology of a large area in eastern Washington that
he correctly attributed to a catastrophic flood. This theory was
considered outrageous at the time, partly, at least, because it was a
departure from the only recently ascendent geological dogma of
uniformitarianism. But more recent research has fully proved him right.
A lake, called Lake Missoula, was created in western Montana by a dam
of glacier ice in northern Idaho. The lake contained some four hundred
cubic miles of water that were released suddenly when melting caused
the dam to fail. The resulting flood, called the Spokane Flood after
the city presently near the upstream end, scoured nearly three
thousand square miles down to bedrock and created huge canyons and
cataracts, one three miles wide. It deposited gravel bars, some of
which contain boulders several feet in diameter, a hundred feet high
and a mile long, topped with giant current ripple-marks ten feet high.
The water ponded behind the Wallula Gap, through which it poured a
thousand feet deep. The peak flow from Lake Missoula, attested to by
current ripples fifty feet high, has been calculated at twenty million
cubic meters per second. (This is fifteen _cubic miles_ per hour. For
comparison purposes, it is one hundred fifty times the mean flow of
the Amazon River and ten or twenty times the total average flow of
fresh water into the oceans of the world.) In a few days, it was all
over.
(Actually, there were a good number of such floods, as the ice dam
reestablished itself. Note added 2011.)
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A fearless man cannot be brave.
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