Geoscience Reference
In-Depth Information
The events of 1952 were totally unexpected for most of the population. Thus,
for example, some of the vessels moored near the Island of Paramushir, transmitted
messages that the island was sinking into the ocean waters.
A. E. Abaev, captain of a detachment of hydrographic vessels sent to Severo-
Kurilsk immediately after the catastrophe, witnessed the strait between the islands
of Shumshu and Paramushir to be completely crammed with floating wreckage
of wooden houses, logs and barrels. The bodies of human beings were seen on
the wreckage—it was practically impossible to survive in the ice-cold water.
Another witness of this tsunami, A. Shabanov, who lived in Severo-Kurilsk and
at the time was 14 years old, told one of the authors of this topic, that soon after
the earthquake the water receded from the coast and left the ocean bottom open.
When Shabanov's mother saw this sudden ebb tide she ran with her two sons to-
wards the hills, which saved their lives. Their family was the only family, in which
no one was killed. On their way they had difficulty in crossing a deep ditch across
which the Japanese in former times had thrown several narrow wooden footbridges.
By 1952, most of the footbridges had been used as firewood, since it was not clear
to the people arriving from the continent what they were for.
The wave that in some parts of the coastline reached a height of 10-15 m
(
H
max
= 18
.
6 m) totally destroyed many buildings and port structures of Severo-
Kurilsk (Island of Paramushir) and carried them out to sea, taking the lives of 2,336
people. The source of the tsunami wave generated by an underwater earthequake of
magnitude M
w
= 9
.
0 extended over 800 km and was about 100 km wide.
The fantastic event that gave rise to a tsunami wave of record height took place
on July 9, 1958 in Lituya Bay (Alaska) [Soloviev et al. (1975)]. The bay exhibits
a T-like shape. Its length amounts to 11 km, its width in the main external part up
to 3 km, and its maximum depth about 200 m. The internal part of the bay is part
of the Fairweather canyon. Here the bay resembles a fjord, and its steep walls rise
up to heights between 650 and 1,800 m. During the earthquake a gigantic slide of
snow-and-ice together with local rock of volume about 0.3 km
3
took place. The wa-
ter ousted by the falling mass splashed out onto the opposite coast and reached
the height of 524 m! The displacement of water was so rapid, that all the trees
in the flooded wood were wrenched up and the bark and leaves of the trees were
rubbed off. Besides this enormous splash, a wave formed that crossed the whole
bay right up to the ocean, devastating the bay's shores. Three fishing-launches
were caught by the wave in the bay; one of them sank together with two crew-
men. The two other crews were lucky to escape. The fishermen spoke of a wave
about 30 m high. Signs of the run-up and of trees broken by the wave remained
on the slope during decades after the catastrophe. Note that the expedition led in
1786 by G.-F. La Perouse encountered a similar phenomenon in the French Har-
bour (presently known as Lituya Bay). An enormous wave carried the two-mast
vessel of the expedition through the narrow strait and smashed it against the under-
water rocks. Of all the 21 crewmen no one was left alive.
The Chilean tsunami of May 22, 1960 was caused by the strongest earthquake
of the twentieth century (
M
= 9.4), the source of which was located in the southern
part of central Chile [Soloviev et al. (1975)]. The maximum elevation of water
amounted to 25 m in Chile, 10.5 m on the Hawaiian islands, 9 m in the Oceania,
