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Posted By: Scott35 Seattle / Olympia Earthquake - 03/02/01 04:44 AM
I just want to express my condolences to anyone on this forum whom either is from the Seattle/ Olympia / Tacoma, Washington areas, or has loved ones living in that area.

Fortunately, the Geological makeup of the fault line and event areas made the event at the surface one that produced minimal damage and injury. Thank God for that!!

I live in Southern California, where there are events occurring on Blind Thrust Faults, a byproduct of the constant banging together of two Tectonic plates at a Strike-Slip fault zone. These produce violent events with numerous aftershocks [or fore cursors].

I must say that due to the recent activity on the Pacific part of the "Ring Of Fire", it was just a matter of time before something of high magnitude would occur in the United States.

We have had very little, if no, activity here in So. California for quite some time. This makes me very nervous! Now that there has been major movement in both the South and North areas of the Pacific plate, it means almost certain increased pressure on the San Andreas. How far the plate has moved north is unknown by me at this time, but when the Northridge quake occurred, the Pacific plate and North American plate moved a total of 6 feet!

I am very interested in seismic activity, and learn quite a bit from each quake. Out here, the best thing we could ever have would be a series of small events. This would release the trapped energy over time, instead of in one large "Snap".

Since we haven't had any series of small to medium events in a long time, plus the recent large movements in the last 2 years, look forward to Southern California having an event soon.

There was a few events in the Big Bear area last year, plus one in the Desert near Barstow / Baker. These might have been aftershocks to the Landers quake, or they are Precursors to a coming large event.

Sorry to be so blunt, and I am truly sorry to the People of Washington, plus Portland, Oregon for their losses and injuries. Just wanted to throw this stuff out. Would make a good thread, too [Linked Image]


Scott.
Posted By: sparky Re: Seattle / Olympia Earthquake - 03/02/01 11:37 AM
has FEMA been involved?
Posted By: Scott35 Re: Seattle / Olympia Earthquake - 03/02/01 01:32 PM
Steve,

They usually respond to the ones out here when there is such a high level of seismic power, and it hits a densely populated area.

I think one news channel mentioned that FEMA would be on site that evening.

I'll get back to you on this one.

Thanks for the concern [Linked Image]

Scott
Posted By: sparky Re: Seattle / Olympia Earthquake - 03/02/01 10:51 PM
I only bring it up because i hear that , after an east coast hurricane a while back, they reorganized, and have apparently been a lot of help.
It's a fairly bad feeling loosing your home to a disaster, so i hope they've been around to ease those individuals and/or families thru this.
I've been nosing around the ARC ( American Red Cross)for a bit, they seem to have almost an underground type of contingent that they can mobilize quickly, so i bet they are involved too.

Steve
[Linked Image]

[This message has been edited by sparky (edited 03-02-2001).]
Posted By: Scott35 Re: Seattle / Olympia Earthquake - 03/03/01 12:18 AM
Steve,

Red Cross is usually the first to arrive, last to leave, when there is a bad event - like the one this week.

They setup temp shelters for the poor victims that have lost their homes, or their home is red-tagged. They also setup Triage areas, and help families connect with out of state members, plus local members. They do a lot.

I am wondering why this quake was downgraded from 7.0 to 6.8 in such a small amount of time. My USGS earthquake report, lists it as Magnitude 7.0 and it was sent that evening. I get worldwide earthquake reports E-Mailed to me when there is an event of magnitude 5.0 or higher in North / Central America, or magnitude 6.0 or higher elsewhere in the world. They are very informative, so are the websites!

Scott.
Posted By: sparky Re: Seattle / Olympia Earthquake - 03/03/01 12:10 PM
I heard something about a scale different than the "Rickter", is that true?
Posted By: Mike Re: Seattle / Olympia Earthquake - 03/05/01 03:46 PM
Scott, Thanks for the words of concern about the Seattle/Olymia earthquake victims. I have relatives living in the Puget Sound area. There was only one earthquake caused fatality (one too many). The female died of a heart attack. I live 130 mile southeast of Seattle. Some residents here felt the earhtquake. I didn't though. Having experienced the 1965 Seattle earthquake, which was only 6.5, I can honestly say "they ain't no fun." What really surprised me about last weeks earthquake was the people didn't know how to take the proper precautions. A majority of them were shown on video running outside instead of diving under tables, desks, etc. Most of us choose where we want to live and natural disasters go with the territory. I picked southeast Washington state which was hit by Mount St. Helens in 1980. [Linked Image]
Posted By: Scott35 Re: Seattle / Olympia Earthquake - 03/05/01 10:26 PM
Steve,

There is another magnitude scale used, which is more "direct" than the familiar Richter Scale - It's called "Modified Mercalli Intensity Scale" and is abbreviated MM
This scale is more aimed to the general public and describes the extent of damage and how the event felt to people, where as the Richter Scale is a mathematical [Logarithmic] scale of magnitude and intensity.

The MM scale uses Roman Numerals to match a scenario list. "I" being the lowest [equal to magnitude 1.0 Richter Scale], and "XII" being the highest [equal to higher than 7.0 Richter Scale].

There's also the "Moment Magnitude" Scale, which is used that is a combination of 3 types of measurements that Richter Scale uses [ML or Magnitude Local, mb or body-wave magnitude, and MS or surface wave magnitude].

Richter Scale intensity is a Logarithm that increases 10 fold [10 log] per full unit.
This means that a 5.0 event has 10 fold the power released than a 4.0 event.
Another example is a magnitude 6.7 releases over 900 times [30 times 30] the energy of a 4.7 earthquake. Inversly, it takes about 900 magnitude 4.7 quakes to equal the energy released in one magnitude 6.7 quake.
A magnitude -1.0 releases 900 times less energy than a magnitude 1.0

Check out the USGS's website for more information.

Mike,

I read about that fatality in the USGS seismic report on that quake. I feel bad for that person's family.
I just can't believe that there was only one fatality, and minimal injury. That is so fortunate!! Out here in So. California, there's typically more casualties, even resulting from a lower magnitude [this is mostly due to the type of fault and the way the energy releases on it].

My Sister lives in Bellevue and my Brother-in-law [her husband] works for Boeing, and was at work when it hit [the big Boeing field / plant at ??? city, can't recall the name off hand].

Washington State had began Seismic Retrofitting and started to adopt some earthquake procedures / protocols, after our Northridge quake of 1994. This event was a major lesson for California, Oregon and Washington.
One good thing is that Washington now has the ideas of Northridge to use for basics, plus this recent event to use for a kind of "Beta Test".
I hope not to sound morbid, but that's the way seismic engineering advances. Each event teaches more and more to all aspects of the field - from the geologists, to the seismologists, to the structural engineers and architects, to the construction worker.

So, you got to see the Mt. St Helens event kind of close [closer than I did]. I'll tell you one thing, with the threat of Volcanoes, Tornadoes and Hurricanes as a function of nature, I'll take the earthquakes anytime!! At least with an earthquake, one can somewhat get away from it's destruction! Can't do that with the other stuff [Linked Image]

When there's one of the early morning earthquakes [the ones that wake a person up at 3:30 AM], we just go outside - away from the house and from danger of falling 12 KV primaries, or exploding gas lines - and just ride the thing out. After the big aftershocks hit, go in the house, check for structural damage, then contact family.

Fortunatly, we do not have any fault lines near us that would put us in the epicentral area of something big, but when the big ones from remote areas come through here, they shake things well!
I can usually feel the P waves that lead the path about 5 to 10 seconds before the S waves come and combine together, causing precursed event [shaking begins].

It's kind of funny; My Wife can't sleep if there's a small noise coming from somewhere - like a TV set on in another room - Whereas I could sleep through a bombing attack!
When an earthquake occurs, I spring awake at the first hint of traveling P waves [almost when the fault snapped!]. My Wife just sleeps right through them! When they get intense enough to cause trouble [more like if they continue building up], then I'll force her out of bed and get her in the yard [where she usually complains that I have woke her for no reason - still groggy!!]

So much for this message.

Scott. SET
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