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NEWS ÜVERVIEW
UnderstandingWorld Events and Trends
Measuring
Earthquakes
O
ne of the most common
ways of measuring
earthquakes is the Richter
scale, devised in 1935 by
Charles F. Richter. lt
measures the amount of
energy released at the
center of an earthquake. For
every increase of one on the
open-ended scale, ground
motion increases 10 times.
Thus a 5.0 quake is 10
times stronger than one
measuring 4.0.
According to the U.S.
National Earthquake
lnformation Center in
Denver, the damage
inflicted depends on
geologic formations of an
area. The chart below is a
generalization.
The Mexico City
earthquake in September
1985, which did more than
US$4,000 million worth of
damage, measured 7.8 on
the Richter scale. lt
showed the destructive
power of a "major' '
earthquake in a populated
area. •
Potential damage to lle expected in populated areas.
8.5
"Great" quake.
May
colapse
even
sturdiest
structures.
7.0
"Majar'' qllllke.
Wid8spreád
damage.
6.0
Can
colapse
weak
struet\nS.
5.5
Can
causecracks
in
structural
fOI.Jidations.
4.0
Can
CIU88
book5
and
sheiYing to
fall.
3.0
Can rattle
windows
==objects.
2.0
l.oweat leYel
normally
falt.
!i:
1
~
Report
Focuseson
Quake
Prediction
For
years scientists have
sought accurate, definite
ways of predicting when and
where earthquakes will
strike.
The goal: to reduce
earthquake losses through
better preparation.
Now the United States
Geological Survey has
published a report, the first
of its kind, detailing recently
developed methods for
forecasting the
consequences of
earthquakes.
The report focuses on the
Los Angeles, Calif., area,
BreasMeeding
M other's milk contains
more than 200 difieren!
substances, sorne of which
provide disease-preventive
benefits in young children.
Mother's antibodies are
passed to her child through
her milk.
Human milk even appears
to offer sorne protection
against diseases to which
the mother has not
developed immunity.
Cholera, which kills about
five million people a year
and is a major killer of
children under 5 in the Third
World, can be prevented in
young children through
which rests on a network of
more than 90 geologic
taults.
" Potentially destructive
earthquakes are inevitable in
the Los Angeles region,"
says the report Geologists
now estímate that the
chance of a large
earthquake occurring along
the San Andreas faull during
the next 30 years is greater
than 40 percent
The report, focusing on
the behavior of bedrock,
could have application to
other urban areas and
should help planners decide
where and what types of
structures to build.
Critica! information on
other factors relative to
earthquakes, such as
groundwater and soil , is still
unavailable.
•
milk-passed antibodies.
Mother's milk also appears
to fight parasites of the
digestive system and can
prevent liver disease
deaths.
These disease-preventive
attributes are importan! in
countries where medicines
and hospital facilities are
expensive and scarce.
A UNICEF report in 1983
warns that in the Third
World bottle-fed babies are
between three and five times
more likely to suffer
malnutrition than breast-fed
babies.
A serious probl('!m with
commercial baby formulas
arises when mothers cannot
read or understand the
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