HDTenEightyP/NetNews huggingface dataset:
From: helfman@aero.org (Robert S. Helfman)
Subject: Re: survey benchmarks
Organization: The Aerospace Corporation, El Segundo, CA
Distribution: ca
Date: Wed, 22 Jul 1992 16:18:41 GMT

In article <1992Jul21.204835.19029@cco.caltech.edu> dreger@seismo.gps.caltech.edu (Doug Dreger) writes:
>In article <1992Jul21.162658.9112@qualcomm.com> karn@chicago.qualcomm.com (Phil Karn) writes:
>>Yes, I believe you're right, but isn't it true that fault zones (at
>>least in California) typically consist of weak, shattered rock a few
>>hundred feet wide so you are never really sure exactly where the
>>surface faulting will occur?....

>
>Just for clarification there are laws in place to try to
>minimize damage in fault zones.
>
>In California there is an act called the Alquist Priolo Act, which
>I believe began soon after the San Fernando EQ.  This act identifies
>known active faults, and outlines a region around the fault in which
>detailed studies to identify past surface offset are required before
>any building can take place.  The act requires trenching of the
>site in any area in which a habitable structure is to be built to
>identify past events in the substrata.

When the Baldwin Hills Crenshaw Plaza mall was built in 1987 or so,
the Alquist Priolo Act required them to do extensive trenching and
tunneling to identify past earth movements. They went down
diagonally 400 feet from one parking lot (of the old shopping center
which the mall replaced) under King Blvd, and under the northern
portion of the site. The trenching/tunneling took about 3 months to
accomplish. An L.A. Times article stated that they found that 
the area had not sustained significant movement within the past 11,000 years.

The construction of the mall used a technique which I had never seen
before. (Because I live on the hill above the mall, I had a perfect
view of the entire demolition, seismic study, and new construction
process for the 2 years that it took.) The area was graded and
a base layer of gravel was put down. Then, large I-beams were bolted into
a huge box - hundreds of feet long - broken up into sections about
50 feet each also separated by the same size of I-beam,
which simply sat on top of the
gravel base. Finally, concrete filled this 2-foot-high 'sandbox' shape. The
upright beams were then bolted to the outside of the box. The result is
an incredibly stable and essentially crack-proof slab. Any engineering
types out there know what that kind of construction is called? (Please,
engineering terms only!)
From: breid@pyrhard2.eng.pyramid.com (Bill Reid)
Newsgroups: ca.earthquakes
Subject: Re: "Hot, dry weather causes earthquakes"
Date: 22 Jul 92 17:43:27 GMT
Organization: Pyramid Technology Corporation, Mountain View

In article <4478@bacon.IMSI.COM> jordan@IMSI.COM (Jordan Hayes) writes:
>
>I read a report recently about how "The Big One" was one of the biggest
>insurance fraud events in history.  Basically, amateur photographers
>who were on the scene soon after the quake doctored "before and after"
>photographs to "prove" that most of the damage had been done after the
>quake by the firestorm.  Most folks didn't have earthquake insurance,
>but they sure as heck had fire insurance.  

There was also a lawsuit over this in the '89 quake, concerning the 
very famous building which burned in the Marina.  The owner had fire 
insurance, tried to collect, and was told "Sorry, but the EARTHQUAKE 
destroyed your building, not the fire".  Photographic evidence has 
been brought in by both sides in this case, and I'm not sure of the 
disposition.  But it sure says something about insurance companies that 
video of your building burning are broadcast worldwide, but you can't 
collect on your fire insurance!!!

>This was in American
>Photographer within the last two years, and was "discovered" after
>years of restoration of the old photos.  A suprising number of them had
>been doctored, and there were some examples of topled chimneys being
>drawn and painted into the pictures ...
>
>As a kid I always heard "The quake was bad, but the *firestorm* after
>did most of the damage!" ...
>
The damage from the quake WAS substansially underreported, as propaganda 
from the SF Chamber of Commerce, including the death toll (officially 
600, but at least 3,000 on up).  But the firestorm that followed was 
so hellacious that most evidence of the quake was removed from the 
face of the earth...
From: mgm@clipper.ingr.com (Mike Marfell)
Newsgroups: ca.earthquakes
Subject: Re: "Hot, dry weather causes earthquakes"
Date: 27 Jul 92 23:38:45 GMT
Distribution: ca
Organization: Intergraph Advanced Processor Division - Palo Alto, CA

In article <Brp6t7.9nn@well.sf.ca.us>, casey@well.sf.ca.us (Kathleen Creighton) writes:
> 
> It's called "earthquake weather", hot and still.  It's always been called
> that.  You'll find out after you've been here for a while because we
> can't go through a period of hot, breezeless weather without *someone*
> saying it.  It's probably a little more mythologized in San Francisco
> because there's almost always at least a breeze.
> Coincidentally, the LP quake did take place during "earthquake weather".
> *Complete* coincidence :-).

> Kathleen Creighton    

    I find that more people comment about "Earthquake Weather" when the
conditions are unseasonably different or strange. For instance, when
we had a fore shock to the Loma Prieta earthquake, about 2-3 months 
earlier, that the weather turned from a warm day to a very cold and
overcast by the evening. :-P

                                                -Mike
-- 

        If you dont have anything nice to say, say it anyway!

Mike Marfell                                      mgm@clipper.ingr.com
Xref: sparky ca.earthquakes:762 sci.geo.geology:1724 rec.radio.amateur.misc:12777 rec.radio.shortwave:5943
From: stead@skadi.CSS.GOV (Richard Stead)
Newsgroups: ca.earthquakes
Subject: Re: building on fault
Date: 24 Jul 92 19:34:29 GMT

In article <mm8eoB2w163w@quake.sylmar.ca.us>, nateh@quake.sylmar.ca.us (Nate Hawthorn) writes:
> They built houses with the ROAD in front RIGHT ON THE FAULT (san andreas)
> and the front driveways are VERY LONG going towards the houses. THere's
> some building code there that says that you can't build within 200
> feet of a known fault!!
>  
> I can't wait for the big one, those houses will be nice firewood for
> the winter!!

I don't see why you think those houses are guaranteed to collapse even in the
big one.  I can show you lots of pictures of buildings much closer than 200
feet to a fault that have survived major quakes.  I can show you lots of
others even over 100 miles from a large quake that have collapsed.  So on
what do you base you assumption that these will collapse?  Do you know the
forces they will experience?  Do you know how they will respond to those
forces?  My assumption here, since you imply they are recent construction,
is that they will survive.  Much better than other, older structures up to
100 miles from the fault.  The earthquake codes that modern structures must
follow work - I have seen the differences personally.  Yes, it turns out
that the engineers know what they are doing, though that apparently surprises
some people.

> What bothers me is that we have to PAY for those houses when they
> declare a "desaster area". I think we should say that anything
> built within 2 miles of a known fault is EXEMPT from any payment of
> our tax dollars!!

Why?  Does your house happen to be 2.1 miles from a fault?  Where do you get
this magic number?  What is its validity?  Do you know how many known faults
there are in CA?  Virtually all of CA would be exempt given you rule.  For
example, ALL of LA is underlain by a detachment fault (more than one actually).
So every spot in LA is directly over a fault.  And the fault is active.
Should we exempt all of the midwest from payment because we know tornadoes
strike there?  How about the entire East Coast and Gulf Coast since they
are known to get hurricanes?  We know that over the past two centuries
tornados and hurricanes have created more damage and cost more tax dollars
than the earthquakes we've had.

> I know that GREED says that we shouldn't WASTE that land, but
> what about the LIVES when a quake hits???

Seems to me that we should be responsible for quality construction to
protect lives.  The greatest loss of life in Loma Prieta was the freeway
collapse - a structure that was known to be earthquake-deficient.  There
are about 8000 buildings in LA known to be quake-deficient.  If you are
really concerned about the loss of life in a quake, you should press to
have those structures upgraded.  When the big one hits, it is those 8000
buildings that will collapse, not the modern wood-frame ones 200 feet from
the fault.

--
Richard Stead
Center for Seismic Studies
Arlington, VA
stead@seismo.css.gov
Xref: sparky ca.earthquakes:781 sci.geo.geology:1735
From: stead@skadi.CSS.GOV (Richard Stead)
Newsgroups: ca.earthquakes
Subject: Re: rain and earthquakes
Date: 21 Jul 92 13:56:35 GMT
Distribution: ca

In article <1992Jul15.202504.9407@aero.org>, helfman@aero.org (Robert S. Helfman) writes:
> 
> For some hair-raising descriptions of the effects of high water tables
> during earthquakes, see the USGS's Earthquake History of the United States and
> an article in Scientific American (sometime in the last ten years, I know at
> least that much) on the 1811-1812 earthquakes at New Madrid, Missouri.
> 
> The sandblows were simply incredible, as you might guess with the
> highly saturated soils to be found adjacent to the Mississippi River.
> Wild geysering, huge waves on the Mississippi, short-lived WATERFALLS
> appearing on the river. When the North American craton does it's next

Right.  The Mississippi actually ran BACKWARDS for an hour or so.  Pretty
impressive.  The course was permanently changed.  A very large lake -
Reelfoot Lake in Tennessee - was formed in the quake.  Most people living
in the area are probably unaware that the quake released more energy than
any other quake in North America during recorded history here.

> big act at New Madrid (and its about 20 years overdue on a 150 year
> cycle), a lot of folks in Memphis are going to find out
> the disadvantages of living in unreinforced brick buildings.

In a reply, Richard Ottolini felt this was "erroneous and alarming".
I disagree.  He is correct in that recurrence rates for intraplate
quakes are generally difficult or impossible to determine.  This is
not true for the New Madrid area.  Several of the faults cut the surface,
and drilling has mapped them at depth very well.  New Madrid is
probably the second most studied fault region in the US after the San
Andreas.  There is a tremendous amount of structural information and
a lot of paleoseismic data.  I can't vouch for the 150 year figure -
I don't have a reference handy - but it sounds short to me.  I thought
average recurrence was closer to 300 years there.  The average recurrence rate
has little meaning in this area since the intervals between quakes vary
a lot.

One of the reasons that New Madrid is an exception to general rules regarding
intraplate quakes is that it's not really a characteristic intraplate
problem.  The New Madrid area is at the tip of a major failed third
arm of rifting related to the opening of the atlantic.  (Rifting is
thought to originate at a point that radiates three rifts 120 degrees
apart.  Two rifts go on to form the ocean, and the third becomes a
failed rift.)  In New Madrid's case, the rifting is continuing, albeit
very slowly.  There are a lot of theories as to why these quakes are so
powerful when the faults are comparatively short, but none can really
be proven or disproven at this point.

--
Richard Stead
Center for Seismic Studies
Arlington, VA
stead@seismo.css.gov
Xref: sparky ca.earthquakes:757 sci.geo.geology:1723
Newsgroups: ca.earthquakes
From: rchilder@us.oracle.com (Richard Childers)
Subject: Re: fax
Organization: Memes-R-Us
Distribution: ca
Date: Wed, 29 Jul 1992 21:32:42 GMT
X-Disclaimer: This message was written by an unauthenticated user
              at Oracle Corporation.  The opinions expressed are those
              of the user and not necessarily those of Oracle.

greg@perry.berkeley.edu (Greg Anderson) writes:

>Mr. Childers, you seem convinced that Mr. Coles is correct.  Fine --
>I don't take issue with the fact that you are convinced.  In fact,
>I invite you to try to convince me.  So, if you have any scientific
>proof, rather than simple criticisms of the scientific method,
>show it to me.  Make your case.  If you manage to convince me, I
>will gladly publicly state the fact that you have managed to do so.

Why would I try to convince you of something that remains to be deter-
-mined ?

Where we disagree, is whether it is worth determining. You seem to know
the answers in advance, such that you can dictate whether a particular
line of reasoning is worth pursuing. This is not scientific method.

>Greg Anderson
>UCB Seismographic Stations
>greg@perry.berkeley.edu

-- richard

-- 
-- richard childers		rchilder@us.oracle.com		1 415 506 2411
         oracle data center  --  unix systems & network administration

                   Klein flask for rent. Inquire within.
Newsgroups: ca.earthquakes
From: karn@chicago.qualcomm.com (Phil Karn)
Subject: Re: survey benchmarks
Organization: Qualcomm, Inc
Distribution: ca
Date: Tue, 21 Jul 1992 16:26:58 GMT

In article <50978@seismo.CSS.GOV> stead@skadi.CSS.GOV (Richard Stead) writes:
>First, I disagree with the basic premise here.  Only if the building actually
>straddles the fault is there any problem.

Yes, I believe you're right, but isn't it true that fault zones (at
least in California) typically consist of weak, shattered rock a few
hundred feet wide so you are never really sure exactly where the
surface faulting will occur? If the faulting misses your structure it
may well survive if it is well built to withstand the shaking because,
as you say, the intensity doesn't vary all that strongly with distance
for the first few miles.  "Peace of Mind in Earthquake Country" also
has some impressive pictures of faults narrowly missing buildings that
were virtually undamaged.

But if you build that close to a fault you are nonetheless taking a
major gamble that the fault won't decide to come up right underneath
you.  Peter Yanev, the author of that book (which I again recommend
*very* highly) argues that building within a few hundred feet of a
known active fault like the Hayward is unconscionable. He
even advocates the abandonment of existing buildings in the fault
zone and the conversion of these zones into parks or preserves.

Of course, this will never happen until the Hayward actually lets go.
And even when it does, the state will probably be so strapped with
general disaster relief spending that there would probably be little
or no money to actually buy those properties directly on the fault.
So the owners will probably take the low-interest disaster relief
loans, rebuild and pass the problem onto their children.

Phil
Newsgroups: ca.earthquakes
From: stgprao@xing.unocal.com (Richard Ottolini)
Subject: Re: Intraplate earthquakes (was Re: rain and earthquakes)
Originator: stgprao@xing
Organization: Unocal Corporation
Distribution: ca
Date: Mon, 27 Jul 1992 16:31:00 GMT

In article <50989@seismo.CSS.GOV> stead@skadi.CSS.GOV (Richard Stead) writes:
>In article <1992Jul22.181833.4044@cco.caltech.edu>, hough@seismo.gps.caltech.edu (Susan Hough) writes:
>> This may well be disintegrating into a question of semantics.  What
>> Johnston & co. has done is to first identify what they term the
>> "stable continental regions" around the world.  These definitions are
>> not based on seismicity but on an assessment of tectonic structure.

I suggested a definition of significant tectonic plates as a consistent
differential motion of one centimeter or more for one hundred thousand
years or more.   This translates into a mimnimum of one kilometer of
differential movement during that time. If a certain fraction of the this
movement is resistive and it turned into seismic energy, then this gives an
estimate of long term seimic energy rates.  Not all plate tectonic motion
is converted into seismic energy, about 10-15%, but still that is a significant
amount. It varies with region.

There are other geophysical and geological criteria for defining a major
plate, but I selected one relevant to estimating seismicity.
Newsgroups: ca.earthquakes
From: rchilder@us.oracle.com (Richard Childers)
Subject: Re: fax
Organization: Memes-R-Us
Date: Mon, 27 Jul 1992 23:21:45 GMT
X-Disclaimer: This message was written by an unauthenticated user
              at Oracle Corporation.  The opinions expressed are those
              of the user and not necessarily those of Oracle.

hauk@s24.es.llnl.gov (Terri Hauk  423-7332) writes:

> This is a sort of backwards approach, if true.

Look up 'deductive' and 'inductive' some day, Oh Brilliant One.

> What exactly *is* the data that he is gathering?

Ask him. Politely.

> What is its source?

Heaven.

>Is he using the optimum equipment and techniques to gather it?

Absolutely not. He's using the cheapest tubes he can buy, to make his
research last a good, long time.

> How does he *know* it's some sort of earthquake pre-cursor signal ?

Spirits told him.

> How does he get directions from a single receiver (no triangulation)?

How do you know he isn't ? ( Jeez. )

>|> Seems to me I've seen some pretty specific articles describing what
>|> his equipment is, who else is helping, and where the data can be
>|> seen - on which bulletin board systems, that is.
>|> 
>
>Please give references on these 'specific articles'!!!!! I would love to see
>them myself. A list of the BBS's where his data is shown would also be 
>appreciated. Funny that he wouldn't post it here under ca.earthquakes, though.
>At a meeting with USGS and others, I understand that Jack Cole was *extremely*
>vague about what he's doing, how and what his data looks like.

I did provide references, and if the reception he gets here is anything like
the reception he gets from the USGS ( which my dad works for, and which I
know has internal politics, like any large organization ), I'm not surprised
that he treats them with a degree of mistrust.

-- richard

-- 
-- richard childers		rchilder@us.oracle.com		1 415 506 2411
         oracle data center  --  unix systems & network administration

                   Klein flask for rent. Inquire within.
Newsgroups: ca.earthquakes
From: karish@pangea.Stanford.EDU (Chuck Karish)
Subject: Re: Intraplate earthquakes (was Re: rain and earthquakes)
Organization: Mindcraft, Inc.
Distribution: ca
Date: Fri, 24 Jul 1992 20:40:29 GMT

In article <50989@seismo.CSS.GOV> stead@skadi.CSS.GOV (Richard Stead) writes:
>Indeed a question of semantics.  All that has been done here is shift the
>ambiguity from what one considers "intraplate" to what one considers an
>"active tectonic feature".  Why does the E. African Rift count as active and
>not the Mississippi embayment?  It seems to me they differ only in degree.

As a whisper and a thunderclap differ only in degree.

The East Africa rift provides spectacular evidence of
ongoing tectonism, including block faulting, high heat flow
leading to broad thermal uplift, and volcanism.  The
Mississippi embayment has undergone very slow subsidence
and we know of one series of earthquakes.
--

    Chuck Karish          karish@mindcraft.com
    (415) 323-9000 x117   karish@forel.stanford.edu
From: thad@public.BTR.COM (Thaddeus P. Floryan)
Newsgroups: ca.earthquakes
Subject: Re: "Hot, dry weather causes earthquakes"
Date: 26 Jul 92 22:13:07 GMT
Distribution: ca
Organization: BTR Public Access UNIX, Mountain View CA

In article <1992Jul22.172704.20914@ttinews.tti.com> paulb@harley.tti.com (Paul Blumstein) writes:
>In article <14f4qbINNe35@agate.berkeley.edu> greg@perry.berkeley.edu (Greg Anderson) writes:
>+The theory of "earthquake weather" actually originated about
>+2500 years ago with Aristotle.  It was his theory that earthquakes
>+were caused by gas trapped within the earth, blowing and 
>+rumbling about, causing underground explosions.  Thus, when the
>+air was still and hot, the theory went, an earthquake was coming
>+because the winds were trapped in the earth.
>+[...]

Hoo, boy, the origins of the Flatulent Earth Society!  :-)

I can just picture the headlines of The Hellenic Times-Daily:

	``TERRAN GAS PASSES MASS''  (or)  ``EARTH GAS MOVES MASS''

Thad Floryan [ thad@btr.com (OR) {decwrl, mips, fernwood}!btr!thad ]
Newsgroups: ca.earthquakes
From: stgprao@xing.unocal.com (Richard Ottolini)
Subject: Re: "Hot, dry weather causes earthquakes"
Originator: stgprao@xing
Organization: Unocal Corporation
Distribution: ca
Date: Tue, 21 Jul 1992 14:50:43 GMT

In article <1992Jul21.035216.931@aero.org> helfman@aero.org (Robert S. Helfman) writes:
>The Great Quake of 1906 in San Francisco occurred
>during a "Mono" wind condition. A Mono is the Northern California equivalent
>of Southern California's Santa Ana condition - a dome of high pressure

The 1989 Loma Prieta quake also happened on a very warm October day.
It was in the 90s at Stanford where I felt it.  The people who slept outside
that night were comfortable temperature-wise.
Xref: sparky ca.earthquakes:767 sci.geo.geology:1727
From: ellon@ADS.COM (Ellon St. Croix)
Newsgroups: ca.earthquakes,sci.geo.geology
Subject: Re: Earthquake forecasting?
Keywords: Earthquake monitoring, Earthquake forecasting, EM pre-cursors
Date: 27 Jul 92 19:15:00 GMT
Organization: Wild Bill & BabyCat's House of Many Pleasures

In article <2A7445B4.16880@noiro.acs.uci.edu> lockhart@mothra.nts.uci.edu (Jack C. Lockhart) writes:
>
>Whoa there!  "THE QUAKE IN THE SANTA CRUZ MOUNTAINS" - the Loma Prieta
>Quake a "FUN QUAKE" ?????  Time for a reality check!  Your incorrect if
>you think no one got hurt from the Loma Prieta Quake in the Santa Cruz
>mountains.  If memory serves 63 people lost their lives; damage was
>widespread and ran in the millions of dollars.  I don't call that a
>"FUN" quake.
>

  Just a minor correction...  There were 67 people killed
  in the Loma Prieta Quake.  And the damages was estimated 
  at 9.7 BILLION dollars.


  Sorry to pick nits, but there was just a segment on 
  Code3(yeah, I know it's trash) on sat, that was kind 
  enough to remind me of why I have this terror of earthquakes. 


  Ellon

  PS.  Perhaps Andy Michael or someone else from the USGS can 
       verify this info.


--
Nothin' feels as good, as good as us together.  Nothin' in the world,
no, there ain't nothin' better than this... NEW LOVE! Always feels 
like a new love. Every touch is feelin' so much like the very first
touch. It's like a new love, a new love........  WCS & ESS 4/18/92 
Newsgroups: ca.earthquakes
From: baalke@kelvin.jpl.nasa.gov (Ron Baalke)
Subject: DSN Update - 07/23/92
News-Software: VAX/VMS VNEWS 1.3-4   
Reply-To: baalke@kelvin.jpl.nasa.gov
Organization: Jet Propulsion Laboratory
Date: Thu, 23 Jul 1992 23:34:56 GMT

                         Deep Space Network Status Report
                                July 23, 1992

     The 70 meter antenna at Goldstone (near Barstow in California) returned
to operations early this morning, supporting the Galileo mission with no
problems.  The antenna has been down since June 28 when the two large
earthquakes damaged its subreflector.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | baalke@kelvin.jpl.nasa.gov
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Most of the things you 
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | worry about will never
|_____|/  |_|/       |_____|/                     | happen.