Download disaster visits afghanistan again

located. The Afghan earthquake created
considerable lateral surface movement
because it was shallow.
In rugged mountains such as the
Hindu Kush, villages are likely to be located on the valley floors or along the
edges of the valley floors because this is
were the agricultural lands are located.
Intermittent streams have deposited loose,
unconsolidated alluvial soils, which are
very subject to lateral surface movements.
For example, a building built on bedrock
may only experience a vibration as the
earthquake shockwave passes, but a foundation built of soft alluvium may experience several inches or feet of displacement, literally shaking a building apart.
Finally, modern technology can comAmid the rubble of years of war in
pensate
for some violent structural moveAfghanistan, a savage earthquake recently
ment
caused
by earthquakes. In the very
killed an estimated 1,800 people and left
simplest
example,
this includes using
10,000 homeless, according to The New
structural
steel,
such
as rebar, in concrete
York Times (March 26, 2002). Can any
to
strengthen
walls.
more disasters befall this troubled counTraditional structural techniques still
try?
used in developing countries such as AfAfghanistan is situated in the middle
ghanistan include the use of stone walls
of one of the world’s most active earthmade by simply stacking uncut stones
quake zones. The region’s frequent and
atop one another to form structural walls.
violent earthquakes have far greater huOthers include the use of
man impacts than most other places
unreinforced mud bricks or cinder
Mother
Nature’s
Wrath
because of the use of inferior buildblocks to form the walls of strucKAZAKHSTAN
MONGOLIA
ing materials. Perhaps 60 percent of
S h a n
KYRG
tures. Even when mortared ton
Afghanistan’s estimated 25 million
e
.
T i
gether, bricks and cinder blocks are
UZBEK.
people reside in houses built of mud
CHINA
TAJIK.
very susceptible to disintegration
Pamir Knot
bricks, stones or cinder blocks.
n S h a n
TURKMEN.
u
from lateral ground movements.
h
t
s
l
Most of the world’s earthKu
A
du
In such poorly constructed resin
i
H
quakes and volcanoes result from
K u
Kabul
dential
buildings, injuries and death
n
geological processes involved with
l u
Islamabad
n
usually
comes from the collapse of
n
S
a
h
plate tectonics. Movements and col- AFGHANISTAN
H i
walls
and
the consequential panm
lisions of huge crustal plates formed
a l
a y
caking
of
the
ceilings and roofs as
a
most of the world’s mountains and
s
PAKISTAN
NEPAL
they fall downward.
New Delhi
wherever these plates interact earthKathmandu
IRAN
BHUTAN
Contrary to the beliefs of some
quakes are common.
who
have never experienced an
The Indian subcontinent rides
BANGLADESH
earthquake,
the shockwave hapon a tectonic plate that moved away
pens
instantaneously
and without
Arabian
Sea
from Pangaea, a supercontinent,
warning.
Every
second
gained by
INDIA
about 210 million years ago. Movhaving
greater
structural
integrity
Bay
of
Bengal
ing from between East Africa and
can
give
residents
time
to
escape
Antarctica, it traveled slowly norththe interior of structures and save
ward and began colliding with the
0
550 mi
lives.
Eurasian plate only about 40 to 50
Afghans asleep in stone build0
550 km
million years ago. The collision has
ings
in the valley villages around
Earthquake Site
been continuing ever since. The
Nahrin,
90 miles north of Kabul
mighty mountain ranges of South
I n d i a n
O c e a n
had
no
time
to evacuate. In fact, as
Asia are products of this ongoing
many
as
1,500
to 2,000 were still
M.
Johnson
collision and the geographic patSRI LANKA
Geography in the News 04/12/02
©2001
missing
a
day
later,
no doubt burtern of these ranges is explained by
ied under the rubble of their homes.
how the collision is occurring.
And that is Geography in the News.
mining how much damage a 6.2 earthThe northernmost tip of the Indian
April
12, 2002. #619.
quake
will
cause,
including
how
close
to
subcontinent struck the Eurasian Plate
the
surface
the
epicenter
is
located,
what
first where the famous Pamir Knot is lo(The author is a Geography Professor at
the building materials are, and what the
cated today, wedging itself into Eurasia.
Appalachian State University, Boone, NC.)
surface materials are where buildings are
The force of the collision over time raised
MYANM
AR
DISASTER VISITS
AFGHANISTAN
AGAIN
the Pamir Knot, a jumble of mountains,
and the mountain ranges that radiate outward. The Pamir Knot became a hinge
point. Today, not only is the wedging
continuing, but the Indian subcontinent
is slowly rotating counterclockwise. This
is forcing the subcontinent to subduct, or
push under, Eurasia. The apparent result
of this rotation is the Himalayas, the
world’s highest mountain range.
Because the collision is continuing,
ongoing tectonic forces are impacting all
of the mountains radiating from the Pamir
Knot. These include the Himalayas,
Kunlun Shan, Altun Shan, Tien Shan, and
the Hindu Kush of Afghanistan. With the
Pamir Knot at the center, these ranges
extend outward around it like the spokes
of a wheel.
Afghanistan’s recent earthquake was
centered 105 miles (169 km.) north of
Kabul and just 40 miles below the surface
in the Hindu Kush. It was only 6.2 on the
Richter scale, the same level experienced
by this author last summer in Bolivia, but
the Afghanistan earthquake was far more
damaging than the one in Bolivia.
Many things come into play in deter-
© 2002 maps.com