From: stgprao@st.unocal.COM (Richard Ottolini)
Subject: Re: The VAN Method
Organization: Unocal Corporation
Distribution: ca
Date: Thu, 20 Aug 1992 15:16:41 GMT

In article <cf#n2g-.bverreau@netcom.com> bverreau@netcom.com (stargazer) writes:
>I found a couple of new earthquake-related books at Kepler's [Menlo Park]
>that might be of interest to readers of this group.  The first is a slim
>volume [134 pp] entitled "Earthquake Prediction", Haroun Tazieff, McGraw-
>Hill, QE538.8T3913 1992.  The work drew some attention in France where it
>was first published in 1989 by M. Tazieff, former director of the French
>National Scientific Research center.  The prediction scheme is called the
>VAN method after the three Greek scientists who developed it, Profs.
>Varotsos, Alexopoulos, and Nomikos.
>
>The VAN theory - for those not previously acquainted - is descended from
>observations reported by John Milne, father of the seismograph, in 1897
>concerning changes in "telluric currents" preceding earthquakes.  Changes
>in the electrical ground potential are claimed to correlate with subsequent
>seismic disturbances.  The following text is the proponents' suggested
>explanation for this phenomenon [bear in mind, this is a Greek-French-
>English translation]:
>The setup for VAN monitoring is minimal compared to the equipment required
>for ULF detection.
>
> "Each of these stations consists of at least two sensors, one oriented
>  north-south and the other east-west.  The principle of these sensors
>  is very simple:  two electrodes buried in the ground several dozen,
>  hundred, or even a thousand feet apart, connected by a conductive wire
>  to a voltage amplifier and a chart recorder."

This method has been tried in the US in the 1970s by Prof Gene Simmons (formaerly of MIT)
and Malcolm Johnson of the Western USGS.  They looked at magnetotellurics
and magnetics somewhere along the San Andreas.  They did not see much,
probably because it was a guiet period.

>Much effort is involved in calibrating each site for local geophysical
>effects.  Characteristic earthquakes must be recorded to establish the
>appropriate electrical 'signature' for a given location.  Triangulation
>is used to estimate the point of origin for a disturbance.  Some sites
>prove unsuitable because underlying features obstruct ground currents.

One hypothesis for earthquake prediction is that each region will have its
own special precusors for prediction.  This is a discouraging possibility
because it means it will take centuries on the West coast to gather enough
data and longer further east.

>
>Tazieff spends much of the book railing against the 'experts'.  An
>example paragraph:
>
> "The explanation for this attitude [hostility to the theory] lies, I
>  believe, in a feeling of frustration associated with the fact that
>  Varotsos, Alexopoulos, and Nomikos are not geophysicists, much less
>  seismologists, but two solid-state physicists (V and A) and an
>  electronics engineer (N), and they are thus outsiders in terms of
>  Earth science.  That these 'outsiders' should have discovered how
>  to predict earthquakes, a result that seismologists could not
>  achieve despite decades of effort, is obviously a difficult thing
>  to forgive.  What is more, if this method were to be officially
>  adopted, the funding allocated each year to research in this area
>  might be taken away from them.  Two good reasons to reject this
>  heretical intrusion without even examining it."
>
>In my mind this is where the book loses a lot of its credibility.
>Paranoia and conspiracy theories are a hallmark of fringe science.

Agreed.
However, very few geophysicists in the US receive training in electrical
methods anymore, so the authors are likely to be experts as anyone else.
I don't think there is a single commercial electrical crew operating in the
US anymore.  Eletrical and EM methods had some utility for sulfide exploration,
but that stopped around 1970 when all mineral exploration in the US halted
except for gold.  Of three prominent schools I attended- MIT, Harvard, and
Stanford- only Stanford had some training in electrical methods and that was
only for a couple of weeks.  And that course (GP191) hasn't been offered in
many years.  Since electrical and EM methods may be able to distinguish
fluids in the near surface, there is some talk of reviving these methods
for environmental studies, but I haven't heard of much of that done.  These
methods are rarely talked about at major geophysics conventions.