|I was wondering about the Mammoth Lakes....
there's some volcanoes there......what is going
to happen in the future????
|Question Date: 1998-01-08|
There are indeed volcanoes at Mammoth Lakes, and
there is a good chance that there will be more to
come. The big question is when? Will there be an
eruption and growth of a new volcano in the next
few years? That is the question that geologists
are trying to answer.
thousand (700,000) years ago a volcanic eruption
larger than any that has been recorded in history,
occurred at Mammoth and formed a twenty mile long
crater that we now call Long Valley. This
eruption was 600 times larger than the eruption of
Mount Saint Helens in 1980; another eruption just
as big could happen again. There are two places
in the 48 connected states of the United States
that are most likely to have a volcanic eruption
in the near future, and Mammoth Lakes is one of
them (the other is Mount Saint Helens).
Long Valley is no longer a smooth, flat crater
depression because other smaller volcanoes have
grown on the valley floor. One of them is Mammoth
Mountain, where there is a large ski area.
Mammoth Mountain is a volcano that began eruption
150,000 years ago and may still be active. The
most vocanically active part of the area is
between Mono Lake and Mammoth Lakes, just outside
the edge of Long Valley.
thousand (40,000) years ago the Mono Craters and
Inyo Craters began erupting, and they have erupted
off and on almost until the present. Over 30 new
volcanic vents opened in the last 2000 years, and
the last eruption was about 500 to 600 years ago.
The most likely volcanic hazard in the area is
that there will be another small eruption like the
ones that have created the Mono and Inyo Craters.
Such an eruption might deposit a layer of ash
eight inches thick, 20 miles downwind and two
inches thick even as far away as 50 miles. The
eruption might last a few weeks or months.
The only volcanic event in the Mammoth
Lakes region that has been recorded by eye-witness
accounts, is a steam blast that occurred on
Mammoth Mountain in 1890. The recent swarm of
earthquake activity, however, may be an indication
that another eruption like those that produced
Inyo and Mono Craters is soon to occur. Such an
eruption would be extremely damaging to towns like
Mammoth Lakes, Lee Vining, and Bishop. Buildings
and streets would be covered with ash, and there
is a good chance that many people would be
Another danger has to do with the
water supply for Los Angeles. An eruption in the
Mammoth Lakes area would contaminate the largest
source of water for the city, Crowley reservoir,
and make it undrinkable. Then Los Angeles would
have to get a lot more water from other places
like northern California and the Colorado River.
This would be very expensive and potentially
damaging to ecosystems.
Well, that is a
long answer to your question. I didn't know all
of this myself. I found most of this information
in a Book called Fire Mountains of the West: The
Cascades and Mono Lake Volcanoes, by Stephan L.
The information about the water
supply to Los Angles, I read in a newpaper article
(the LA Times, I think, although I couldn't find
it again!). Let me know if you have any more
Seven hundred thousand (700,000) years ago there
was a HUGE eruption in LONG VALLEY, near Mammoth
Lakes. The amount of magma erupted was about
600cubic kilometers !!!...The residual activity
that we see today is related to that giant
eruption 700,000 years ago.
there were small eruptions near the Chain of
Craters road...about 600 years ago..the indians
saw these eruptions.
As far as the future,
no one can say...it is very likely that there will
be eruptions in the future...however, it is
virtually impossible to say if they will come
within the next year, 10 years, 100 years or even
You see, geologic time scales are
far longer than human lifetimes...what is needed
is to monitor the Mammoth Lakes area for quakes as
well as the release of volcanic gases, so that we
can make better volcano predictions. Also, the
swelling of the ground due to magma movement and
/or storage can tell us that something MAY
happen...but to predict an actual time is
impossible now; we just dont know enough. If you
study hard and learn a lot aboout geology maybe
someday you can be a geologist who specializes in
volcanology and therefore work on a problem like
this, as I do.
Basically, no one knows for sure what will happen
at Mammoth mountain because it is impossible to
make an accurate prediction. Scientists have to
make an educated guess based on the data that they
have. The problem is that there is not much data
to warn when a volcano eruption is coming. (It is
similar to the way that a light bulb burns out.
After you have been using a light bulb for a long
time, you know that the chance that it will burn
out becomes greater, but you can't predict just
exactly when it will burn out.)
are worried about Mammoth mountain because the
number of earthquakes in the area around the
mountain have increased recently. Also, the
amount of gases like carbon dioxide in the air
near the lakes has increased. This means that the
chance for an eruption is greater, but no one can
The clues that an eruption will
occur are very small and not always reliable, but
as technology improves, scientists can measure
these clues better and make better guesses about
Here's a web site I
found if you want to learn
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