EARTHQUAKES AND HISTORY
BY LORRAINE BERTAN,
On Friday October 30, 2020,
a -7 magnitude earthquake
occurred in the Aegean
Sea, affecting Greece and Turkey.
The quake was most severe in the
Turkish city of Izmir, where 115
people died and many were injured.
The Greek island of Samos was affected
by tsunamis originating from
the undersea earthquake. Tsunamis
are associated with earthquakes
occurring near coastal areas.
Shock waves can continue after
earthquakes, and Turkey has been
experiencing shock waves through
November 8, 2020.
Japan experienced a -9 magnitude
earthquake in March 2011, which
occurred in the northeast area of
Tohoku on Honshu Island and
was accompanied by a devastating
tsunami with waves over 100 feet
high. Shocks from this magnitude
-9 earthquake were felt all over the
world, from the fjords of Norway to
the washing up of material on the
western coast of the United States.
Earthquakes are the results of
plate tectonics within the earth.
The structure of the earth includes
the crust, the inner and outer mantle
and the outer and inner cores.
Potassium, uranium and thorium are
radioactive elements that produce
heat along with the residual heat
from the formation of the planet.
This heat provides the energy for
convection currents within the
mantle. It is convection that causes
the movement of the plates and the
resultant motion of the continents
riding on the plates. Plates may
crash into each other producing
mountain ranges, or plates may subduct
forming the violent subduction
zones associated with the Alaskan
earthquake in 1964.
Volcanoes are associated with
subduction zones, and the Cascade
Mountains in the United States are
volcanoes, like Mount St. Helens
and Mount Rainier, Lassen Peak,
Mount Hood and many others.
The Cascade range extends from
Southwestern British Columbia
through Washington, Oregon and
Northern California. The Cascade
Volcanic Arc is part of the Pacific
Ring of Fire that experiences
earthquake and volcanic activity.
Tsunamis are associated with these
areas, and the high population
zones of Portland and Seattle are
a serious concern. An earthquake
occurred in that area in about 300
years ago, unleashing a tsunami
described in Native American
legends, and scientists are investigating
the area for fossil evidence
of that tsunami.
The San Francisco Earthquake
of 1906 was a result of movement
along the San Andreas Fault. The
San Andreas Transform Fault is
the junction of the Pacific Plate
and the North American Plate.
Earthquakes result when plates
slip, overcome friction and release
energy which causes shaking. As
a result of the fire after the earthquake,
the city of San Francisco
was destroyed and 250,000 people
died. The human tragedy and
property loss of the earthquake had
an impact on financial markets.
British insurers paid out claims at
a massive rate, disrupting the fixed
Sterling/Dollar rate and had to
raise interest rates which discriminated
against American goods. A
recession resulted, which led to
the Panic of 1907. The rebuilding
of San Francisco ended on a more
positive note. City planners were
able to develop a more beautiful
and efficient design to replace the
helter-skelter disorder of the 1849
Gold Rush city plan.
The Japanese Earthquake and
Tsunami of March, 2011 had resultant
economic aftershocks which
affected the population. Japan
is located on the Pacific Ring of
Fire and has experienced earthquake
and volcanic throughout its
existence, which is substantiated
through meticulous record keeping.
Experience has taught the Japanese
the value of structurally resistant
buildings and incorporated a tradition
of cooperation within the
population. Only 100 people lost
their lives in the earthquake, but
over 20,000 people lost their lives
in the 100 foot high waves of the
tsunami. The tsunami flooded the
power supply of the Fukushima
Daiichi nuclear Power plant, disabling
the cooling mechanism and
meltdown occurred, elevating contaminated
water and gases into the
ocean and atmosphere. This was a
triple disaster for Japan and affected
the population and economy.
Since there is a tradition of cooperation
among the Japanese, there
was rapid emergency evacuation and
rebuilding to get back to normal.
However, the extensive uprooting of
population and manufacturing centers
caused disruption in supply networks
and the economy took a hit,
$360 billion in losses, making the
Triple Disaster the most expensive
in history. Japan is currently experiencing
trade deficits. What was most
problematic was the meltdown and
contamination of the nuclear power
plant, which is monitored by the
World Health Organization. New
government regulations have been
put in place and two of the nuclear
power plants are in operation. The
unique cooperation of the Japanese
population during the disaster and
afterward has engendered the admiration
of the world.
The Alaskan Earthquake of 1964,
-9.2 magnitude, was the largest ever
recorded in North America. Like
the Japanese Earthquake of 2011,
massive tsunamis affected the populations
of Oregon and California, and
the Space Needle Building in Seattle
swayed. Anchorage, and most of the
population of Alaska, sustained damage
because of its proximity to the
eastern part of the Aleutian Trench
where the earthquake occurred.
Property damage was $2.3 billion
and 129 lives were lost. Shipping
and transport were affected, Alaska’s
important industries. Since modern
geologic instruments were available
at that time, scientists learned a
great deal about subduction zone
earthquakes and have developed
technology to measure earth movements.
Although science can predict
areas where quakes will occur, they
cannot determine specific times, only
“if” and not “when.”
There are other geologically active
zones within the earth, the “hot
spots” like Hawaii, Yellowstone,
Iceland and the Galapagos. “Hot
Spots” are volcanoes that form
on tectonic plates, like the Pacific
Ocean for Hawaii and the North
American Plate for Yellowstone.
Earthquakes and volcanoes usually
occur at plate boundaries,
while “hot spots” may occur in
the middle of a tectonic plate. The
Yellowstone “Hot Spot” is situated
on the most massive volcano ever
measured, and is hot enough to
provide the heat for the geysers at
Yellowstone, but it is not erupting.
Iceland occupies the mid-Atlantic
Ridge, the opening of the Atlantic
Ocean, and its most recent volcano
of “Eyjfjallajokull” affected airline
travel over the summer of 2010.
The earth is a chaotic place and
we have to learn to live with it.
October 30, 2020 Earthquake in Aegean Sea
January 2021 ¢ NORTH SHORE TOWERS COURIER 29