Tectonic Hazards

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Tectonic Hazards

• A PowerPoint of images to accompany the notesheet

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EARTHQUAKES Mexico City 1985 Ground shaking
PRIMARY HAZARD Long Waves Nature of surface
(dried up lake bed)
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Loma Prieta epicenter PRIMARY (San Francisco
1989) Marina District badly affected Foundations
on rubble infill after 1906 earthquake. Lessons
not learnt so repetition of disaster. SECONDARY
fire
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Leninakan Armenia PRIMARY HAZARD On December 7,
1988, a magnitude 6.9 earthquake shook
northwestern Armenia Collapse of floors leaving
walls standing in building in Leninakan. This
three-story building is one of the older
buildings. Most of the newer one-and two-story
dwellings and two- and three-story commercial
buildings in Leninakan received little damage.
250000 deaths.
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When liquefaction occurs, the strength of the
soil decreases and, the ability of a soil deposit
to support foundations for buildings and bridges
is reduced see the overturned apartment complex
buildings in Niigata in 1964. SECONDARY HAZARD
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LANDSLIDES Earthquakes can dislodge glacier
chunks causing disastrous mudflows.
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Tsunami e.g. Banda Ache Asian Tsunmai December
26th 2004 SECONDARY HAZARD
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VOLCANOES
Basalt lava flow Kilauea , Hawaii Predictable and
not too hazardous PRIMARY HAZARD
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Pyroclastic flow is composed mainly of volcanic
rock and dense ash material and is ejected from
an exploding volcano. Up to 200 kph. PRIMARY
HAZARD
Death by pyroclastic flow can be terrifyingly
brutal. In less than a second, the body is
submerged in fire... the first breath vaporizes
the internal organs... the pain barely has a
chance to register... the body is almost
instantly reduced to charcoal
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ASH FALL PRIMARY HAZARD
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VOLCANIC GASES On August 21, 1986 is erupted in
quite an unexpected manner. The lake itself
basically turned over, allowing trapped gas to
diffuse all at once, creating an enormous pool of
CO2 that killed more than 1700 people and their
livestock. PRIMARY HAZARD
The Great Farting Lake of 1986 Lake Nyos
Cameroon
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Lahars SECONDARY HAZARDS
In the aftermath of Pinatubo, Phillipines every
year in heavy rains more lahars occur. The
eruption was 1991.
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Lahar Nevada del ruiz worst volcanic disaster
of 20th Century
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Mt. St Helens LANDSLIDE triggered
eruption SECONDARY HAZARD
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TSUNAMI 1999 New Guinea SECONDARY HAZARD
Destruction at the village of Teles, located at
the outer edge of the area inundated by the
tsunami.  In many areas, bare house poles and
debris where all that remained of homes.  A total
of 10,000 survivors lost their homes and personal
possessions.