- 1. A 6+M Earthquake will occur before
the end of April 1998, with a confidence of 75%. (Note: a 3 in 4 chance)
- 2. An Eruption, possibly just phreatic
(Steam) will occur prior to the end of April 1998, with a confidence of
20%. (Note: a 1 in 5 chance) Note: Prediction 2 is subject to possible
increase if the circumstances warrant.
- Reasons: 1. Thousands of quakes have
occured in the Mammoth Lakes area over the last 4 months. There were 500+
in a single day. 2. CO-2 and sulfurous gas releases are ongoing. Trees
are dying. 3. There has been a 2" swelling of the surface of the
Long Valley Caldera. 4. There has been a dramatic shallowing of the focii
(depth of the earthquakes) to nearly ground level. "The only things
lacking are large quakes of 6+M and harmonic tremors. Then we will have
conditions that preceded past volcanic warnings."
- Additional Notes: Not just Mammoth Lakes,
but the whole Sierra Nevada range seems to be bouncing now. It is starting
to become very interesting.
- James Berkland noted that the volcanic
windows fill in the gaps between seismic windows and often overlap by a
day or two. Six of seven of the major St. Helens eruptions were between
the Seismic Windows and the one big exception was the Big Blast of May
18, 1980, which was triggered by the 5.2M seismic event under the peak
on that day.
- Jim Berkland:
- "I have been observing the same
patterns at Mammoth Lake, and it seems the focii are getting shallower,
which is a bit ominous. I know that the USGS is also carefully monitoring
the activity there but are reluctant to talk much about it as they were
badly burned in 1980-82, when they pointed out the possibility of an eruption,
much to the dismay of the local ski resort operators and Chamber of Commerce.
(You might want to remember the basic storylines of Jaws and Dante's Peak,
- The geologists were not much appreciated,
although they were just doing their jobs. With the current climate of el
Nino, so-called Global Warming and the Ozone Hole, there is a limit to
how much the public will take before becoming immune to real hazards.
If the CO-2 levels rise and the ground begins to swell, then I will have
real concern and put out my own alert. Meanwhile I believe the current
3-month swarm of little ones is unprecedented, and the whole Sierra Nevada
seems agitated from south to north.
- I don't consider it totally coincidental
that Mount Saint Helens blew in May of 1980 at the same time that the biggest
'recent' events of 6M+ shook the Mammoth Lakes area. Similarly, when the
7.5M Landers quake of June 28, 1992 hit, there were quakes triggered at
Mammoth, Shasta, Lassen, Yellowstone, etc."
- As of this Update: U.S.G.S.'s official
condition is Condition "GREEN". A condition "Yellow Watch"
on November 22nd was reported by the Associated Press but later denied
by the USGS, although the criteria for the designation appeared to have
- The official ratings by the USGS have
no effect upon earlier predictions by Jim Berkland. Further developments
may increase the probability for surface volcanism, but a truly catastrophic
explosion is not anticipated.
- An article by AP stated that "MAMMOTH
QUAKES INITIATE YELLOW ALERT" ... On Sunday, Dave Hill, the U.S. Geological
Survey's chief scientist for Long Valley, was investigating the latest
spate of volcanic activity, which registered a high of 600 quakes Nov.
17, and more than 2,000 temblors in the past week. A condition yellow watch
was called on Saturday, meaning there was intense geological unrest. The
condition yellow is called when earthquake swarms have at least one magnitude-5
quake or there is evidence of magma movement and ground deformation.
- It is clear that quakes of 4.5, 4.5,
4.7 and 4.9M on one day do not quite equal the required 5M minimum, but
the continued tilt anomaly at "Postpile" and other factors would
normally dictate a Yellow designation for two weeks.