From: andy@pangea.Stanford.EDU (Andy Michael USGS Guest)
Newsgroups: ca.earthquakes
Subject: Re: Parkfield
Date: 23 Dec 1992 23:43:20 GMT
Organization: Stanford Univ. Earth Sciences
Distribution: ca
NNTP-Posting-Host: pangea.stanford.edu

In article <1992Dec23.192337.11061@netcom.com> alden@netcom.com (Andrew L. Alden) writes:
>andy@pangea.Stanford.EDU (Andy Michael USGS Guest) writes:
semantic arguments deleted.

>: No one ever suggested that the Parkfield experiment was a test of the
>: characteristic earthquake hypothesis.  The instrumentation at Parkfield
>: is there to record details of the preparation period before an
>: earthquake, the earthquake itself, and the time period afterwards in
>: great detail.  
>All the public knew was that the government (NEPEC) had forecast a quake
>before 1993, and the USGS would set up a monitoring and warning system
>for our benefit.  That forecast was absolutely based on the 22-year
>repetition model, and the factors you cite--assessing precursors,
>rupture dynamics etc.--are consequential, not constitutive.

Given the filter between us and the public this may very well be both
the way the public sees it and not true.  The warning system is quite
clearly considered a secondary part of the experiment in the documents
that describe it.

"The primary goal of the Parkfield prediction experiment is a detailed
understanding of the geologic processes that precede the anticipated
earthquake."

"A secondary goal of the Parkfield experiment is for the USGS to issue a
short-term warning of the anticipated earthquake."

Both from Bakun, 1988, Earthquakes and Volcanoes, v. 20, page 42.
1988 may seem late, but these passages were written about two years
earlier.  This issue took a long time to get published.

After all it would be rather foolish to make issuing a short term
warning the primary goal of your experiment when you don't even know
that such warnings are theoretically possible.  However, both the alert
scheme and the long term prediction seem to be more exciting to the
news media.  The most exciting science to come out of the experiment
uniformly doesn't make the news, even when we try to push it.

>The forecast, based on that model, drove the whole enterprise.

In reality there was a move towards having a prototype intensive
monitoring experiment before the Bakun and Lindh model for Parkfield was
proposed.  Thus, it really didn't drive the whole enterprise.  It
certainly made it more fundable, but it wasn't the only factor.

>I may have posed my question too provocatively for Andy, who is
>certainly correct.  I don't mean to impugn Bakun, Lindh, or McEvilly in
>the slightest.  I (and Andy, I hope) come down on the "ignorantly
>simple" end--knowing that in science, "ignorant" is not a pejorative
>term.  For funding purposes, the test question had this advantage: it's
>as easy to understand as betting on a coin coming up "heads" when it's
>done so six times in a row already.  This is easy to sell!  I'm glad
>Andy can attest to people's probity.  But now that we know that simple
>recurrence is too simple a model, we need to guard against the tendency
>to sound-bite the next model we use to justify projects like Parkfield.
>I think with Parkfield the danger is past, since its benefits, in
>addition to the (in my opinion) sterile scientific model it tested, are
>so obvious.

I might prefer the word "optimistic" to ignorant.  But I think we have
gotten to the point of semantics.  I do find such questions provocative
because some journalists, perhaps weaned on Watergate, are always looking
for real scandals as oppossed to sterile scientific debates.  I've even
been asked if the reasons for differences between USGS and Berekely
magnitudes result from political differences between the groups!

Sound-biting is a definite problem, but again a media driven one.
Scientists will stoop to giving soundbites, but usually because the
choice is between getting no coverage (which sounds like an egotistical
reason) and therefore communicating nothing to the public (which sounds
like a more altruistic one).  I do agree that the coverage of this has
been over-simplified and that there are large differences between how
the scientific community and the public view this experiment.  Solving
this is a much larger problem than Parkfield, but an extremely important
one if the public is going to understand and play a role in controlling
the science that the government funds.  Perhaps one important
addition would be a good historic study of the project.  One is under
way, but may have started too late.  Another is focussing more on the
way large collaborations work rather than the specific science of the
Parkfield experiment.

Andy