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The World's Largest
Calderas
These Are the World's
Largest Calderas
By Andrew Alden
Calderas are
large craters formed by volcanic explosions or by unsupported surface rock
collapsing into empty magma chambers beneath the ground.
They
sometimes are referred to as supervolcanoes.
One way
to understand calderas is to think of them as reverse
volcanoes.
Volcanic
eruptions often will be the cause of magma chambers being left empty and leaving the
volcano above unsupported.
This
can cause the ground above, sometimes an entire volcano, to collapse into the
empty chamber.
Yellowstone Park
Yellowstone Park is perhaps the most well-known caldera
in the United States, drawing millions of
tourists every year.
According
to Yellowstone's website, the supervolcano was the site of massive
eruptions 2.1 million years ago, 1.2 million years ago, and
640,000 years ago.
Those
eruptions were, respectively, 6,000 times, 70 times, and 2,500 times more powerful
than the 1980 eruption of Mount St. Helens in Washington.
Explosive Force
What
today is known as Lake Toba in Indonesia is the result of perhaps the greatest
volcanic eruption since the dawn of early man.
Approximately
74,000 years ago, Mount Toba's eruption produced about 2,500 times more
volcanic ash than Mount St. Helens. This led to a volcanic winter that had a
devastating effect on the entire human population of the time.
The
volcanic winter lasted six years and led to a 1,000-year-long ice age,
according to research, and the world population was reduced to about 10,000
adults.
Potential Modern Impact
Research
into how a massive eruption would impact the world day shows the effects to be
potentially devastating.
One study focusing on Yellowstone suggests another
eruption comparable in size to the three biggest ones of the past 2.1
million years would kill 87,000 people instantly. The volume of ash would
be enough to collapse rooftops in states surrounding the park.
Everything
within about 60 miles would be destroyed, most of the western United States
would be covered in about 4 feet of ash, and an ash cloud would spread across
the entire planet, casting it in shadow for days.
The
impact on vegetation could lead to food shortages across the planet.
Visiting the Largest Calderas on the Planet
Yellowstone is
just one of many calderas throughout the world. Like Yellowstone, many of the
others can be interesting and fascinating places to visit and to study.
Below
is a list of the world's largest calderas:
Caldera name
|
Country
|
Location
|
Size
(km) |
Most
recent eruption |
La Pacana
|
Chile
|
23.10 S
67.25 W |
60 x 35
|
Pliocene
|
Pastos
Grandes |
Bolivia
|
21.45 S
67.51 W |
50 x 40
|
8.3 Ma
|
Kari Kari
|
Bolivia
|
19.43 S
65.38 W |
30
|
Unknown
|
Cerro Galan
|
Argentina
|
25.57 S
65.57 W |
32
|
2.5 Ma
|
Awasa
|
Ethiopia
|
7.18 N
38.48 E |
40 x 30
|
Unknown
|
Toba
|
Indonesia
|
2.60 N
98.80 E |
100 x 35
|
74 ka
|
Tondano
|
Indonesia
|
1.25 N
124.85 E |
30 x 20
|
Quaternary
|
Maroa/
Whakamaru |
New
Zealand |
38.55 S
176.05 E |
40 x 30
|
500 ka
|
Taupo
|
New
Zealand |
38.78 S
176.12 E |
35
|
1,800 yr
|
Yellowstone
|
USA-WY
|
44.58 N
110.53 W |
85 x 45
|
630 ka
|
La Garita
|
USA-CO
|
37.85 N
106.93 W |
75 x 35
|
27.8 Ma
|
Emory
|
USA-NM
|
32.8 N
107.7 W |
55 x 25
|
33 Ma
|
Bursum
|
USA-NM
|
33.3 N
108.5 W |
40 x 30
|
28-29 Ma
|
Longridge
(McDermitt) |
USA-OR
|
42.0 N
117.7 W |
33
|
~16 Ma
|
Socorro
|
USA-NM
|
33.96 N
107.10 W |
35 x 25
|
33 Ma
|
Timber
Mountain |
USA-NV
|
37 N
116.5 W |
30 x 25
|
11.6 Ma
|
Chinati
Mountains |
USA-TX
|
29.9 N
104.5 W |
30 x 20
|
32-33 Ma
|
Long Valley
|
USA-CA
|
37.70 N
118.87 W |
32 x 17
|
50 ka
|
greater Maly
Semiachik/Pirog |
Russia
|
54.11 N
159.65 E |
50
|
~50 ka
|
greater Bolshoi
Semiachik |
Russia
|
54.5 N
160.00 E |
48 x 40
|
~50 ka
|
greater
Ichinsky |
Russia
|
55.7 N
157.75 E |
44 x 40
|
~50 ka
|
greater
Pauzhetka |
Russia
|
51 N
157 E |
~40
|
300 ka
|
greater
Ksudach |
Russia
|
51.8 N
157.54 E |
~35
|
~50 ka
|
Andrew
Alden
Geology Expert
Education
B.A., Earth Sciences, University of New
Hampshire
Introduction
Professional geologist, writer, photographer,
and geological tour guide
Thirty-seven years of experience writing
about geological subjects
Six years as a research guide with U.S. Geological Survey (USGS)
Experience
Andrew Alden is a former writer for
ThoughtCo who contributed hundreds of articles for more than 17 years. Andrew
works as a geologist, writer, editor, and photographer. He has written on
geological subjects since 1981 and participates actively in his field. For
example, Andrew spent six years as a research guide with the U.S. Geological Survey,
leading excursions on both land land and at sea. And since 1992, he has hosted
the earthquakes conference for the online discussion platform, The Well,
which began as a dialogue between the writers and readers of the Whole Earth
Review.
In addition, Andrew is a longtime member
of the member of the Geological Society of America — an international
society that serves members in academia, government, and industry; and
the American Geophysical
Union — a community of earth and space scientists that
advances the power of science to ensure a sustainable future.
Andrew lives in Oakland, California; and
though he writes about the whole planet and beyond, Andrew finds his own
city full of interest too and blogs about its
geology.
Education
Andrew Alden holds a bachelor's
(B.A.) degree in Earth Science from the University of New Hampshire,
College of Engineering and Physical Sciences, in Durham, N.H.
Awards and Publications
Andrew Alden on Earthquakes (The Well Group, Inc., 2011)
Assessment of River — Floodplain Aquifer Interactions (Environmental
and Engineering Geoscience, 1997)
Andrew
Alden on Hosting (The Well Group, Inc., 1995)
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