![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhIKlymXn07mJOkjLWcs0B1iZ61bFELXmD9dSpwyJx94aYKQXxwsPskjWG1sZaZqQmBUstCCGyN29wasbLttb3g4cgucyCTH0WEnGb-BvfV1MRF_Bjzth441cqYVSDqilUTlXnKQbNeBMs/s320/bay.jpg)
Alaska's
Lituya Bay had been used for many years as a temporary shelter for
boats traveling the eastern Pacific, but no one lives there permanently.
In fact, the local Tlingit people told the legend of a monster at the
mouth of the bay who shook the ocean to send huge waves. They knew what
was going on. The unique geography of the bay amplifies waves to a
terrifying extent. Travelers were there when the largest tsunami wave in
recorded history blew through Lituya Bay in July of 1958. It reached
about a third of a mile up the shore, destroying everything in its way.
It started with a magnitude 8 earthquake.
The earth
shook for anywhere from one to four minutes—eyewitness reports varied.
When the fault finally came to rest, the foamy water of Lituya Bay
settled back into something resembling its ordinary lazy waves, and a
new quiet blanketed the bay. Despite the cessation of shaking, Orville
and Mickey Wagner on the Sunmore—the boat headed for the bay
exit—continued their retreat toward the open ocean.
After a
minute or so of apparent calm, a crash described as “deafening” rattled
the atmosphere. One of the unnamed mountain peaks that stood at the
inland end of Lituya Bay had broken off, dropping ninety million tons of
rock into the water with the force equivalent to a meteor strike. The
resulting impact shook loose other rocks on the slopes, and chunks of
adjacent glaciers, and these plunged into the water practically all at
once. Millions of cubic yards of displaced water heaved upward and
formed a wave traveling outward at about 110 miles per hour (180 km/h).
Within
about a minute, the approaching wave became visible to the boats still
at anchor, and the occupants looked on in awe as the wide skyscraper of
water traversed the length of the bay towards them. When it reached
Cenotaph Island another minute or so later, the proportions of the wave
became clear. The center of the wave was almost as high as the highest
point on the island, 300 feet in the air. On the two opposite shores,
the plowing saltwater reached over 1,700 feet (over 500 meters) onto
land, twisting even the most massive trees from their roots and scraping
the bedrock nearly clean.
Read
the story of the Lituya Bay megatsunami, gleaned from eyewitness accounts and the geologic record, at Damn Interesting
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