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The history of big earthquakes in the United States helps to predict future quakes. It also includes some in place you probably wouldn't expect. There is a list of the most famous quakes and a map of the historical earthquakes below, followed by details of the quakes.
Although it is possible, scientists are not convinced that there will ever be another catastrophic eruption at Yellowstone. Given Yellowstone's past history, the yearly probability of another caldera—forming eruption could be calculated as 1 in 730,000 or 0.00014%. However, this number is based simply on averaging the two intervals between the three major past eruptions at Yellowstone — this is hardly enough to make a critical judgement. This probability is roughly similar to that of a large (1 kilometer) asteroid hitting the Earth. Moreover, catastrophic geologic events are neither regular nor predictable.
Such a giant
eruption would have regional effects such as falling ash and
short-term (years to decades) changes to global climate. The
surrounding states of Montana, Idaho, and Wyoming would be affected,
as well as other places in the United States and the world. Such
eruptions usually form calderas, broad volcanic depressions created
as the ground surface collapses as a result of withdrawal of
partially molten rock (magma) below. Fortunately, the chances of this
sort of eruption at Yellowstone are exceedingly small in the next few
thousands of years.
Yellowstone monitored for volcanic activity. The Yellowstone Volcano
Observatory (YVO), a partnership between the United States Geological
Survey (USGS), Yellowstone National Park, and the University of Utah,
closely monitors volcanic activity at Yellowstone. The YVO website
(http://volcanoes.usgs.gov/yvo) features real-time data for
earthquakes, ground deformation, streamflow, and selected stream
temperatures. In addition, YVO scientists collaborate with scientists
from around the world to study the Yellowstone volcano.
There is no evidence that a catastrophic eruption at Yellowstone is imminent, and such events are unlikely to occur in the next few centuries. Scientists have also found no indication of an imminent smaller eruption of lava.
(Year - month - day - time)
|1.||Cascadia subduction zone||1700 01 26 UTC||˜9|
|2.||New Madrid, Missouri||1811 12 16 08:15 UTC||8.1|
|3.||New Madrid, Missouri||1812 02 07 09:45 UTC||˜8|
|4.||Fort Tejon, California||1857 01 09 16:24 UTC||7.9|
|5.||San Francisco, California||1906 04 18 13:12 UTC||7.8|
|6.||Imperial Valley, California||1892 02 24 07:20 UTC||7.8|
|7.||New Madrid, Missouri||1812 01 23 15:00 UTC||7.8|
|8.||Owens Valley, California||1872 03 26 10:30 UTC||7.4|
|9.||Landers, California||1992 06 28 11:57 UTC||7.3|
|10.||Hebgen Lake, Montana||1959 08 18 06:37 UTC||7.3|
|11.||Kern County, California||1952 07 21 11:52 UTC||7.3|
|12.||West of Eureka, California||1922 01 31 13:17 UTC||7.3|
|13.||Charleston, South Carolina||1886 09 01 02:51 UTC||7.3|
|14.||California - Oregon Coast||1873 11 23 05:00 UTC||7.3|
|15.||N Cascades, Washington||1872 12 15 05:40 UTC||7.3|
Note: Widely differing magnitudes have been computed for some of these earthquakes; the values differ according to the methods and data used. For example, some sources list the magnitude of the 8.7 Rat Islands earthquake as low as 7.7. On the other hand, some sources list the magnitude of the February 7, 1812 New Madrid quake as high as 8.8. Similar variations exist for most events on this list, although generally not so large as for the examples given.
In general, the magnitudes given in the list above have been determined from the seismic moment, when available. For very large earthquakes, the moment magnitude is considered to be a more accurate determination than the traditional amplitude magnitude computation procedures. Note that all of these values can be called "magnitudes on the Richter scale," regardless of the method used to compute them.
All earthquake dates are UTC, not local time.
This page was updated on 23-Mar-2017