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At 11:42 A.M. on Tuesday, July 29, 2008 a 5.4M event occurred near Chino
Hills, CA (San Bernardino County). The light quake was widely felt, but did little in terms of serious or widespread
consequences. This is the first quake of any note in the LA region in a number of years that was not out in the desert,
such as the Hector Mine quake of 1999.
The aftershock sequence as of evening the same day seem to be typical.
Already low probabilities of the initial quake being a foreshock have declined appropriately and a higher magnitude
quake directly related to the same series is fairly unlikely.
Earthquake Solutions notes the sheer number of comments, claims and advice
that have been given on various media reports that are often confusing, and all too often inaccurate or false, especially
relating to safety advice. The best behaviors to use DURING the shaking, and what to do first when the shaking first
STOPS are two different things, and BOTH issues are frequently misunderstood. For more information, contact us to schedule
an engaging and informative program that is designed specifically to help prevent earthquake injuries and save lives.
Employers and business owners have obligations to protect their workforce
and customers. History exists to indicate that businesses that fail to prepare properly and who are seriously impacted
by any kind of disaster or lengthy infrastructure disruption may suffer enough loss and disruption of operations to lose their
businesses in less than three years. A quake of today's magnitude is unlikely to have those effects, but many businesses,
schools, and yes, even government agencies, have a lot of work to do on their preparedness, response, recovery and continuity
plans in order to avoid serious consequences in the future.
Neighborhoods, non-profits and faith communities should also be encouraged
to develop and test plans, and to include in those plans accurate life safety information, and a look at the long-term recovery
issues.
We trust that most of those concerned with this quake will be able to
obtain updates through their regular news sources. However, dial 626-256-7900 or email earthquakesolutions@earthlink.net to schedule more specific assessment services, dynamic and interactive programs
and seminars, help with drill design, observation and debriefing services, to buy products, and anything else to do with disaster
preparedness. We're here to help!
Please keep in mind that we are emergency management specialists and not seismologists
or geologists. As to the science of earthquakes, we have no special expertise beyond that which results from strong
interest and motivation to continually learn more about the field. We strive to stay reasonably informed and aware
of seismic developments and various theories about earthquake probabilities.
Please note that we have now pulled out volcanic activity to a separate
page. Please click on the underlined phrase below to check out this new link:
Before getting into some of the Southern California quakes in recent months, it is important to note a current
series of quakes is occurring in Baja, not too far from the south end of the Salton Sea. Many seismologists believe
that the next time the master fault goes, the San Andreas, it will probably initiate from the Salton Sea section.
Recent quakes of interest in California include the following:
- On 8/9/07 a 4.5 occurred 4 miles NNW of Chatsworth, 5 km deep.
- On 8/16/07 a 3.5 occurred 4 miles N of Chatworth, 5 km deep.
- On 8/29/07 a 3.7 occurred 5 miles ESE of octobillo Wells (near the Salton
Sea), 1 km deep.
- On 8/30/07 a 3.5 occurred in the greater San Diego urban area, 7
km deep.
- On 8/31/07 a 3.5 occurred in Central California about 8 miles south of
Hollister, 2 km deep.
- On 9/1/07 a 6.3 occurred in the Gulf of California. This one was
56 km deep.
- On 9/2/07 a 4.7 occurred 11 miles SSE of Corona at 10:29 AM. It
was 2 km deep.
- On 9/4/07 a 4.0 occurred 7 miles SW of La Jolla at 7:47:59 AM. It
was 9 km deep.
- On 9/8/07 a 4.0 occurred 26 miles SW of Camp Pendleton and 28 miles WSW
of Carlsbad. It was only 2 km deep.
- On 9/17/07, a 3.5 occurred in Northern California about 9 miles ENE of
Hidden Valley Lakke, and 52 miles NNE of Santa Rosa. It was 9 km deep.
- On 9/23/07, a 3.5 occurred 5 miles SW of Ocatillo. This one
was 5 km deep.
- On 9/25/07 a 3.9 occurred 8 miles WNW of Lake Elsinore at 1 km deep.
- On 9/28/07 two quakes were above feelable level in California. A 3.9 occurred 44 km deep 21 miles WNW
of Coalinga, and a 4.1 occurred 32 km deep 38 miles ENE of Chico.
Of course the world also grieves for the loss of life and devastation in
the wake of the Peru earthquake and many heavy aftershocks. We also note the 5.2 event in Honduras on 9-15-07 (34 km
deep), a large quake that occurred in Bolivia as well, and a 5.9 off the coast of Ecuador on 9-26-07 (91 km deep), in
addition to heightened activity around the Pacific Rim.
This has been an usually active recent season throughout the Pacific Rim.
It is not unusual to have clusters of quakes out in the Pacific Ocean, and quite a few of them. Numbers are way up because
of aftershocks of the Indonesian quakes, but also at more distant locations that would normally be said to be unrelated.
Many quakes have been of moderately high magnitudes, including a 7.3 quake off the coast of Auckland Island near New
Zealand on 9-30-07, anda 7.4 in the Mariana Islands region.
At this point the recent rash of high magnitude quakes in Indonesia is
continuing. Some of the aftershocks of the two most major events have exceeded the magnitude of the Northridge
earthquake (CA) on January 17, 1994 and the Kobe, Japan quake of January 17, 1995 (Yes! The Anniversary!) There
have been some tsunami issues, but mild in comparison to the 12-26-04 massive tsuanmis that took lives in over ten countries.
San Andreas - News and Views:
The British journal "Nature" recently released a new study indicating
the southern end of Southern California's master fault, the San Andreas, appears to be overdue for a catastrophic earthquake.
According to Yuri Fialko, the study's creator, "The observed strain rates confirm that the southern section
of the San Andreas fault may be approaching the end of the interseismic phase of the earthquake cycle."
In a way,
this is not really news. Other studies provide similar information. However, this study took advantage of improved
monitoring available in recent years in obtaining data by satellite. Previous measurements of strain through ground
stations were taken in much larger intervals of over 6 miles between stations. The satellite readings were much more
precise at intervals of about 66 feet. This appears to be the most precise proof yet indicating that a quake of
massive size may be "imminent".
The problem
with the word "imminent" is that it is expressed in this case in geologic terms, which can include very long intervals.
And of course, no one, not even the best scientists, can predict when it will happen.
The important
thing to know is that it willl indeed inevitably and eventually happen, and that the likely impacts on a now highly urbanized,
high population region are probably beyond our full ability to understand in advance of such an actual occurrence. One
aspect though that is highly probable, almost to a degree of certainty, is that very large areas will likely to cut off from
any outside help for many days.
What you
know, and what you have, when it happens, will be your only and total resource pool to draw on. Lives will be on the
line, and some of them will be people you care about. Sign up now for our high quality training courses, and renew
your supply stockpiles and plans.
Each minute
longer since the last quake, is a minute closer to the next one.
Posted 6-27-06
Hawaii Quake in October, 2006
A 6.7 quake on October 15 hit at 7:07 AM, 10 miles north-northwest of
Kailua-Kona, on the west coast of Hawaii Island (known commonly as the "Big Island". It was the strongest quake to hit
the islands in more than two decades. Preliminary damage estimates just a few days later were for $46 million dollars,
and Presidential disaster was delcared, opening the way for federal aid.
Seven schools and a harbor were damaged, and there were road failures,
landslides and other problems. Businesses lost at least 4.89 million. No deaths or serious injuries were reported.
Most areas of the Big Island were blacked out initially, as well as nearly all of the neighboring island of Oahu, with more
than 800,000 residents. However, most utility services were over 90% restored within about 24 hours.
The quake struck a 4,000 plus square mile area. Most
of the land there is undeveloped or agricultural. The effects of this quake were also lessened over what they could
have been, because the epicentral area was actually offshore and not a direct hit.
By contrast, a quake of the same magnitude in densely populated Southern
California (Northridge, 1994) caused over $50 billion in damages, between insured losses, infrastructure damage, federal government
assistance and other sources, as well as loss of lives and thousands of injuries.
This quake was NOT a volcanic earthquake, but a tectonic one, which are
harder to predict in this region. According to an article by the Associated Press, scientists explain that as volcanoes
in the region grow, their weight presses down on the crust, and can cause it to give way. "It's like someone sitting
on a mattress", said Jim Kauahikaua, USGS scientist in charge of the Hawaiian Volcano Observatory. "The crust is flexed
by the weight of the island."
Notable quakes and/or Ring of Fire activity:
For information
on the MASSIVE earthquake that caused the horrendous tsunamis on 12/26/04, please click on the following link:
It may be important to remember that the deeper
and/or larger a quake, the more effects it can have over significant distances. For example a previous Bolivian
quake that was very deep had traceable effects as far north as Canada, and the 7.1 Landers quake in Southern California on
June 28, 1992 had traceable seismic effects as far north as Yellowstone National Park.
***
To see what areas where affected, and to what degree click on the following
link:
Did you feel it? Help seismologists and responders, no matter how
lightly you felt it, by filling out the on-line survey at the following link:
Did you feel it?
So, what's happening on the San Andreas?
Click the link immediately below for something to think about:
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