HDTenEightyP/NetNews huggingface dataset:
From: barroux@licancabur.Corp.Sun.COM (Juan Carlos Barroux - Technical Consultant - Latin America)
Newsgroups: ca.earthquakes
Subject: Re: types of earthquake predictions
Date: 24 Dec 1992 01:53:17 GMT
Organization: Sun Microsystems, Inc.
Distribution: world
Reply-To: barroux@licancabur.Corp.Sun.COM
NNTP-Posting-Host: licancabur.corp.sun.com

In article 51678@seismo.CSS.GOV, stead@skadi.CSS.GOV (Richard Stead) writes:
>
>The 1960 Chile quake had Mw=9.6 (Mw is an open-ended magnitude scale,
>Richter magnitude saturates at about 8.5 and cannot get larger).  It
>is the biggest quake during instrumental seismology.  But there is evidence
>it may well be the largest quake in several centuries.  It broke a fault
>area 800 km long and 200 km wide, and the sides slipped about 20 meters.
>Hard to beat that for size.  It was so big it made the earth wobble measurably,
>and the rang like a bell for weeks.  
>--
>Richard Stead

  Since I am Chilean I have heard a lot of stories about that quake. My
mother and my father in law actually worked in the relief effort in the
area just a few days after the quake. One of the main problems was that
a principal river was completely cut-off by a hill which decided to
landslide on top of it, creating a huge dam. Obviously, there was a
mayor city on the path of the river, so the dam had to be destroyed
quickly. Most of the earthmoving equipment of the country was used to
that purpose.

  I just went back from a trip to Chile and some friends told me that
they are expecting another earthquake on the same fault as the 1960
one. They told me that only the lower portion of the fault did fracture
and not the upper part. They also are worried about a quake in the
north part of the country, near the frontier with Peru. 

  Is this true?

  Speaking for himself,

  Juan Carlos

Newsgroups: ca.earthquakes
From: gak@wrs.com (Richard Stueven)
Subject: Re: Quake felt in Menlo Park 1pm Sunday
Reply-To: gak@wrs.com
Organization: Wind River Systems, Inc.
Date: Tue, 22 Dec 1992 00:27:37 GMT

In article 1h5m1kINN5rk@gap.caltech.edu, hough@seismo.gps.caltech.edu (Susan Hough) writes:
>In article <1h5g6fINNj9b@agate.berkeley.edu> greg@perry.berkeley.edu (Greg Anderson) writes:
>>
>>OK, here's the info from us here at UCB and from the USGS in Menlo Park.
>>UCB:
>>Location:  1 mile NNE of San Leandro (San Leandro Hills)
>>		37 degrees, 44.7 min North
>>		122 degrees, 08.6 min West
>>		depth = 2 miles
>>Magnitude: Mw 3.6
>
>Thanks Greg, for posting all of this.  My question regarding this event
>has to do with the tv shots of cracked chimneys & such--all of that for
>a M3.6-ish event?  Just a function of the relatively shallow depth?
>Or extreme site effects near the source?  Or extreme poor construction
>near the source?

Interesting...I live in San Leandro, but I wasn't at home during the
"event".  I didn't notice anything out of place* when I got home last
night, and in fact I didn't even know we had had an earthquake until I
saw the articles on ca.earthquakes this morning.

go figure
gak

---
Richard Stueven        gak@wrs.com         attmail!gakhaus!gak        107/H/3&4

        I'm always more outspoken after a few pints of Guinness.
                - Mrs. E. Slocombe

*I have a whole bunch of beer glasses that are going to become rubble
 when we get a good jolt.
From: Zio zZz <zio@Garg.Campbell.CA.US>
Newsgroups: ca.earthquakes
Subject: Re: Quake felt in Menlo Park 1pm Sunday
Date: Tue, 22 Dec 92 01:27:56 PST
Distribution: ca
Organization: The Land of Garg

tweek@netcom.com (Michael D. Maxfield) writes:

> In article <1992Dec21.002841.2664@leland.Stanford.EDU> gsroka@leland.Stanford
> >I felt a small but very noticeable amount of shaking while
> >[...]
> >this be from a long distance medium quake, or from a very close but small
> >one?  Does anyone know if and where the epicenter was?
> 
> Yes, I felt it in Moraga too.  It felt like one single `drop' or shake.  
> According to the callers on the radio, a lot of them felt two quakes...
> the sudden jolt one and a shaker afterwards.  I wonder why I missed the 
> second one?  The epicenter was reported to have been in San Leandro and a
> first report placed it at 3.3 while latter reports said it was between 3.5
> and 4.0.  (Probably two different sources and the media decided to take
> the larger one for the SENSATIONALIZATION FACTOR.)
> 
> Other news reports have mentioned fireplace chimney damage in Oakland.
> 
I think I felt the 'jolt' one in San Jose.  It felt to me like the floor 
changed height about an inch instantly.  The only time I ever felt that 
type of a jolt was a second or two before a nice M5ish roller hit.  P and 
S Wave stuff, prolly...can't remember exactly what happened on that one - 
was a while back.  I knew that an earthquake was bound to be on the way, 
or had already occurred long distance.  Then I got home and heard about 
it, and noted that I was only about 2 minutes off on the reported time, 
so it had to be the one.


-- 
zio@Garg.Campbell.CA.US (Zio zZz)
The Land of Garg BBS -- +1 408 378-5108
Newsgroups: ca.earthquakes,sci.space
From: stgprao@st.unocal.COM (Richard Ottolini)
Subject: Re: SPOT images of the Landers quake deformation
Organization: Unocal Corporation
Distribution: ca
Date: Tue, 22 Dec 1992 16:31:50 GMT


I wonder if the two images could be posted to the network.
I suspect not because of copyrights.
From: art@acc.com (Art Berggreen)
Newsgroups: ca.earthquakes
Subject: Stress Map
Date: 22 Dec 92 16:51:31 GMT
Organization: ACC, Advanced Computer Communications

Well, the stress map that I asked about a couple of weeks ago just
showed up in my latest issue of Science News.  So I'll ask the
question again.

Is an online version of this graphic available?
(It appears to be computer generated)

Art
Newsgroups: ca.earthquakes
From: barrus@cod.nosc.mil
Subject: Re: types of earthquake predictions
Organization: Naval Ocean Systems Center, San Diego, CA
Date: Mon, 21 Dec 1992 16:53:17 GMT


In article <51678@seismo.CSS.GOV> usenet@seismo.CSS.GOV writes:
>In article <1992Dec18.225447.23143@gordian.com>, mike@gordian.com (Michael A. Thomas) writes:
>>   <snicker>
>> 
>>   Wouldn't a magnitude 15 sort of, er, split the earth in half?
>> But just for fun, is there any guestimate as to what the largest
>> magnitude earthquake was in, say recent geological history? I've
>> heard that the Chilean quake was close to 9 but is there any 
>> evidence of quakes much bigger than that?
>
>The 1960 Chile quake had Mw=9.6 (Mw is an open-ended magnitude scale,
>Richter magnitude saturates at about 8.5 and cannot get larger).  It
>is the biggest quake during instrumental seismology.  But there is evidence
>it may well be the largest quake in several centuries.  It broke a fault
>area 800 km long and 200 km wide, and the sides slipped about 20 meters.
>Hard to beat that for size.  It was so big it made the earth wobble measurably,
>and the rang like a bell for weeks.  Now, imagine 240 million of those
>all at once - that's a magnitude 15 (energy goes up by a factor of 30
>for each unit of magnitude).
>
>Just so's you know, that's more energy than splitting the earth in half.
>It's enough energy to melt the earth.
Wasn't the Alaskan Earthquake around a 9 as well?


Newsgroups: ca.earthquakes
From: bobg@rains.wpd.sgi.com (Bob Green)
Subject: Re: Quake felt in Menlo Park 1pm Sunday
Reply-To: bobg@rains.wpd.sgi.com (Bob Green)
Organization: sgi
Date: Mon, 21 Dec 92 15:14:38 GMT


Yep, a 3.7 almost directly under my home in San Leandro.  It was a
hard and quick (one to two seconds) shock that did no damage to
my neighborhood.  I could swear that there was more of a vertical
shock than a horizontal.
-- 

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
	Bob Green
	Silicon Graphics Computer Systems
	2011 N. Shoreline Blvd.
	Mountain View, CA 94039

	Email: bobg@sgi.com
	Phone: (415) 390-3438
From: andy@pangea.Stanford.EDU (Andy Michael USGS Guest)
Newsgroups: ca.earthquakes
Subject: Re: Parkfield
Date: 23 Dec 1992 23:44:52 GMT
Organization: Stanford Univ. Earth Sciences
Distribution: ca
NNTP-Posting-Host: pangea.stanford.edu

In article <35550010@hpcuhe.cup.hp.com> campbelr@hpcuhe.cup.hp.com (Bob Campbell) writes:
>I have been following the Parkfield experiment with some interest, but the
>talk of the end of th "window" at the end of the month leads me to ask if
>the instrumentation is to be kept running after the 1st, or is it going to
>close up shop?

The instrumentation will keep running at least through this fiscal year
(which ends in October 1993).  Future changes to the experiment will
depend on a number of factors of which the most important is an external
review that should be released soon.  Can't wait to see it myself.

Andy
From: erc@Apple.COM (Ed Carp)
Newsgroups: ca.earthquakes
Subject: Re: Quake felt in Menlo Park 1pm Sunday
Date: 22 Dec 92 20:41:38 GMT
Organization: Bleeding Edge Technologies - 'Sliding Down The Razor Blade Of Life...'

I was in the South Bay (Santa Clara) and didn't feel anything.  Bah, humbug...
I come out for the weekend, something exciting happens, and I don't even feel it.
Bleh.
-- 
Ed Carp, N7EKG                    erc@apple.com                   801/538-0177
"This is the final task I will ever give you, and it  goes  on  forever.   Act
happy, feel happy, be happy, without a reason in the world. Then you can love,
and do what you will."           -- Dan Millman, "Way Of The Peaceful Warrior"
From: stead@skadi.CSS.GOV (Richard Stead)
Newsgroups: ca.earthquakes
Subject: Re: types of earthquake predictions
Date: 21 Dec 92 21:04:37 GMT

In article <1992Dec21.165317.5851@nosc.mil>, barrus@cod.nosc.mil writes:
> 
> In article <51678@seismo.CSS.GOV> usenet@seismo.CSS.GOV writes:
> >The 1960 Chile quake had Mw=9.6 (Mw is an open-ended magnitude scale,
> Wasn't the Alaskan Earthquake around a 9 as well?

Yes, it was a 9.4, the second largest quake in instrumental seismology.
Now that I look them up, however, I can't find the paper that labelled
1960 Chile as 9.6 and 1964 Alaska as 9.4.  I can find Hiroo Kanamoris'
paper where he measured several Mw, and found 9.5 for Chile and 9.2 for
Alaska.  Other big quakes:
1906 Ecuador     8.8
1922 Chile       8.5
1923 Kamchatka   8.5
1938 Banda Sea   8.5
1950 Assam       8.6
1952 Kamchatka   9.0
1957 Aleutians   9.1
1963 Kuriles     8.5
1965 Aleutians   8.7

Note that these are all associated with subduction (Assam is really
continental collision, but that's related to subduction), and are located
at the world's deepest and most active subduction zones.


--
Richard Stead
Center for Seismic Studies
Arlington, VA
stead@seismo.css.gov
From: jane@soave.swdc.stratus.com (Jane Beckman)
Newsgroups: ca.earthquakes
Subject: Re: types of earthquake predictions
Date: 23 Dec 92 01:41:00 GMT
Distribution: ca
Organization: Stratus Computer, Inc., San Jose, CA

Oh great, they're just changing the years on the Nostradamus
bunk, now.  "Gee, it didn't happen in '92, so that must mean
it was really supposed to happen in '93."  I predict (with
more accuracy) yearly updates to the disaster dates.

--
  Jilara   [jane@swdc.stratus.com]

"The field of pseudo-science hasn't progressed much in ten
years, except to gain access to the net." --from ca.earthquakes
From: skod@trenco.Eng.Sun.COM (Scott Griffith, Sun Lumpyware)
Newsgroups: ca.earthquakes
Subject: Re: Quake felt in Menlo Park 1pm Sunday
Date: 21 Dec 92 16:15:34 GMT
Organization: Sun Microsystems, Mountain View, CA
NNTP-Posting-Host: trenco

In article <1992Dec21.002841.2664@leland.Stanford.EDU> gsroka@leland.Stanford.EDU (Gregory Sroka) writes:
>I felt a small but very noticeable amount of shaking while
>watching the Bills-New Orleans game. It was a bit unusual in that
>it's the first one I've felt in quite a few months, and that it
>was small and quick, but the leaves on our plants kept vibrating
>for several seconds after we felt it.

Well, here's another me-too. I was at home in Foster City, and this
was the first noticeable shake since we moved to landfill heaven- so I
was _very_ interested in how things would behave. I was sitting on the
living room floor wrapping Christmas presents, so my butt was well
coupled to the slab- I got two nice sharp little shocks within 100 ms
or so, then a gap of some 1-2 seconds, then about 15 seconds of 
gentle shaking at about 1hz. Peak displacement apparent from the
chandelier was about 1/4". Most amusing- it'll be interesting to see
how the jello under the house behaves when the local faults get around
to the next act...!

-skod

--
Scott Griffith, Sun Microsystems Lumpyware
expatriate SCCA New England Region Flagging/Communications worker
(and sometimes driver, of anything that turns both right and left,
and can pass tech...) Return Path : skod@trenco.Eng.Sun.COM
From: readingj@nic.cerf.net (John D. Reading)
Newsgroups: ca.earthquakes
Subject: Re: Parkfield
Date: 26 Dec 92 18:19:03 GMT
Distribution: ca
Organization: CERFnet Dial n' CERF Customer Group
NNTP-Posting-Host: nic.cerf.net

In article <1hd656INNpuu@morrow.stanford.edu> andy@pangea.Stanford.EDU (Andy Michael USGS Guest) writes:
>In article <1992Dec24.191159.20528@netlabs.com> lwall@netlabs.com (Larry Wall) writes:

[Suggestions for artificially triggering a Parkfield quake deleted

I hate to jump in on topics about which I know relatively little,
but hey, it is kind of slow...

According to Urban Folklore, aren't we supposed to import everyone
in China and have them jump up and down at once in the Parkfield
area?  :-) :-)

John Reading
readingj@cerf.net
From: hough@seismo.gps.caltech.edu (Susan Hough)
Newsgroups: ca.earthquakes
Subject: Re: Quake felt in Menlo Park 1pm Sunday
Date: 22 Dec 1992 00:04:04 GMT
Organization: California Institute of Technology, Pasadena
NNTP-Posting-Host: earth.gps.caltech.edu

In article <1h5g6fINNj9b@agate.berkeley.edu> greg@perry.berkeley.edu (Greg Anderson) writes:
>
>OK, here's the info from us here at UCB and from the USGS in Menlo Park.
>UCB:
>Location:  1 mile NNE of San Leandro (San Leandro Hills)
>		37 degrees, 44.7 min North
>		122 degrees, 08.6 min West
>		depth = 2 miles
>Magnitude: Mw 3.6

Thanks Greg, for posting all of this.  My question regarding this event
has to do with the tv shots of cracked chimneys & such--all of that for
a M3.6-ish event?  Just a function of the relatively shallow depth?
Or extreme site effects near the source?  Or extreme poor construction
near the source?

Sue Hough 
Newsgroups: ca.earthquakes
From: news@sco.com (News admin)
Subject: Re: types of earthquake predictions
Organization: The Santa Cruz Operation, Inc.
Date: Mon, 21 Dec 1992 14:48:32 GMT



Can the person who posted the article on Nostradamus Prediction e-mail it
to my account please.

I deleted it by mistake.

Thank you,
Sandra
sandrav@sco.com
From: alden@netcom.com (Andrew L. Alden)
Newsgroups: ca.earthquakes
Subject: Real-time quake detection
Date: 21 Dec 92 23:55:36 GMT
Organization: Netcom - Online Communication Services  (408 241-9760 guest)


Real-time earthquake warning systems are getting closer, as shown at the
American Geophysical Union's meeting in San Francisco on December 10.

After the October 1989 Loma Prieta quake, emergency workers at the fallen
Cypress freeway structure in Oakland benefited from a jury-rigged
aftershock detector; telemetry directly from the South Bay aftershock zone
gave rescuers a few seconds' notice before seismic waves arrived.  Since
that time, efforts in northern and southern California have brought about
widespread automated detection networks--and trained personnel to put their
output to best use.

Egil Hauksson (Caltech) described progress in the Caltech - USGS Broadcast
of Earthquakes, or CUBE, project which began in early 1991 and now includes
eleven member agencies and utilities.  The time, location, and magnitude of
seismic events are broadcast to belt pagers and computers in near-real
time, which "minimizes confusion and allows for immediate response of
emergency management personnel," Hauksson said.  The system affected
responses in all three major southern California quakes in 1992.  Now the
project is tying in Terrascope, the state-of-the-art regional seismic
array, to get faster and better magnitude estimates and to alert CUBE
members of areas of strong ground motion.  CUBE's long-term aim is to build
a seismic computerized alert network, or SCAN, for the south state.

The Berkeley Seismographic Station is doing similar work in the Bay area,
upgrading its instruments, installing seismographs at new sites and tying
in Stanford's seismic station.  In June the station started work with USGS
and UC Berkeley's Earthquake Engineering Research Center to share data in
near real time and issue joint announcements within minutes of significant
quakes in central and northern California, said Barbara Romanowicz.

Pacific Gas & Electric Company has a telemetry prototype working that can
sense seismic events and inform the central control room in San Francisco
within 5 seconds.  Using a display of the Bay area and its main electrical
network that is updated every second, controllers can actually watch the
shock spread as it trips alarms throughout the system--presumably while
bellowing out warnings and orders.  PG&E's Woody Savage showed a simulation
of this setup, using the data from Loma Prieta, and it was quite a sight.

Every second of warning can help utilities protect sensitive equipment,
disconnect relays, back up computers, and start rerouting power.  Emergency
doors can be opened, response agencies can be alerted, and dispatchers can
guide field technicians to where they're most needed.

Copyright 1992, alden@netcom.com--please keep this notice with this story.
From: andy@pangea.Stanford.EDU (Andy Michael USGS Guest)
Newsgroups: ca.earthquakes
Subject: Re: Parkfield
Date: 24 Dec 1992 20:21:58 GMT
Organization: Stanford Univ. Earth Sciences
Distribution: ca
NNTP-Posting-Host: pangea.stanford.edu

In article <1992Dec24.191159.20528@netlabs.com> lwall@netlabs.com (Larry Wall) writes:
>You should tell them about the planned New Year's Eve party down there,
>at which everyone will jump up and down in unison to see if they can help
>it along...  :-)

No, no, no!  Parkfield legend has it that you have to poor coffee on the
fault.  And yes, it has already been tried. :-)  Smiley because it was
done as a joke, not because it wasn't actually done.

Andy
Newsgroups: ca.earthquakes
From: stead@skadi.CSS.GOV (Richard Stead)
Newsgroups: ca.earthquakes
Subject: Re: the coming "big" one
Date: 29 Dec 92 02:37:34 GMT
Distribution: ca

In article <1992Dec28.232226.11317@wvus.org>, pete@wvus.org (Pete Gregory) writes:
> Why is the coming "big one", estimated at (what was it?) 8.5, figured to
> cause such widespread damage, when its Richter value is only a little
> higher than the Big Bear and Landers quakes earlier this year?
> Geographically, their distance from metro L.A. is not that different.
> Experts, please enlighten me...

First, 8.3 is not "only a little" larger than Landers.  It represents almost
30 times the energy of the Landers quake.  In addition, the "Big One (TM)"
will be closer to major population than Landers.  Both of these factors will
contribute to greater damage.  I personally consider the damage and casualty
estimates for the 8.3 to be over-estimated.  However, I do not dispute this
practice, it is important to err on the side of caution.



--
Richard Stead
Center for Seismic Studies
Arlington, VA
stead@seismo.css.gov
From: c@wet.UUCP (Chuck Charlton)
Newsgroups: ca.earthquakes
Subject: Re: Quake felt in Menlo Park 1pm Sunday
Date: 23 Dec 92 04:22:15 GMT
Distribution: ca
Organization: Wetware Diversions, San Francisco

I felt it in the Richmond district of San Francisco.  I was sitting quietly,
and I thought it was either an earthquake in the South Bay, or two large
trucks had driven by silently, three seconds apart.  I noted the time, then
I went back to watching the 49ers.

Newsgroups: ca.earthquakes
From: pete@wvus.org (Pete Gregory)
Subject: the coming "big" one
Organization: World Vision U.S.
Distribution: ca
Date: Mon, 28 Dec 92 23:22:26 GMT

Why is the coming "big one", estimated at (what was it?) 8.5, figured to
cause such widespread damage, when its Richter value is only a little
higher than the Big Bear and Landers quakes earlier this year?
Geographically, their distance from metro L.A. is not that different.
Experts, please enlighten me...
-- 

Pete Gregory, World Vision U.S.   Internet: pete@wvus.org
                                  Bangpath: ames!elroy!wvus!pete
From: andy@pangea.Stanford.EDU (Andy Michael USGS Guest)
Newsgroups: ca.earthquakes
Subject: Re: Parkfield
Date: 24 Dec 1992 20:20:31 GMT
Organization: Stanford Univ. Earth Sciences
Distribution: ca
NNTP-Posting-Host: pangea.stanford.edu

In article <1992Dec24.011255.3268@netcom.com> alden@netcom.com (Andrew L. Alden) writes:
>Andy, thanks for a nice exchange.  While we're on the subject, why don't
Glad we're having fun and for the opportunity to say how we think about it.

>you post a bit about how you applied the "A alert" criteria to the
>historic instrumental record at Parkfield?  That didn't get any press,
>but I liked the research.

Actually I borrowed that slide from Bill Bakun, its his work, and the
criteria were designed around the historic record.  Here's how the
alert criteria should have worked had they existed in 1934 and 1966:

1934:
Two felt forshocks on June 5.  Assumming felt events were at Middle
Mountain and were above magnitude 2.5, then the first would be a
C level alert and the second would combine with it to produce a B
level alert.  A magnitude 5 event that is clearly at Middle
on June 6 creates an A level alert and public warning.  The foreshock
17 minutes before the mainshock on June 8 would extend the A level
alert for 72 hours, but the M6 mainshock occurs on June 8.

1966:
On June 16 cracks in the ground along the San Andreas fault are observed.
If these are signs of fault creep (and not dessication of the mud from
lack of rain) then this could be a C level creep alert (the actual level
is a bit of a guess).  On June 27 a irrigation pipe breaks where it
crosses the San Andreas with San Andreas style motion.  If this is a
larger creep event the experiment might now be at a B level alert.  But
once again this is sort of a guess (Peter Malin calls the pipe "an article
of faith for the true Parkfield believers."  BTW, he's not a critic of
the project but operates the downhole digital seismic network there).
9 hours later an M5 event creates an A level alert and 17 minutes later
the M6 mainshock occurs.  Of course, it may be hard to do much with
only 17 minutes warning unless everything is automated.

Remember, the alert criteria were designed so that they would have been
as successful as possible for these two cases.

Andy
From: lwall@netlabs.com (Larry Wall)
Subject: Re: Parkfield
Organization: NetLabs, Inc.
Distribution: ca
Date: Thu, 24 Dec 1992 19:11:59 GMT

You should tell them about the planned New Year's Eve party down there,
at which everyone will jump up and down in unison to see if they can help
it along...  :-)

Larry Wall
lwall@netlabs.com
Newsgroups: ca.earthquakes