PSN-L Email List Message

Subject: Re: Earthquake prediction messages
From: Ed Thelen ethelen@........
Date: Mon, 18 Sep 2000 01:49:54 -0700

Larry Cochrane wrote:
> All,
> I just sent an email asking the person who is sending the earthquake
> "predictions"  messages too stop posting to our list. In my opinion, and
> others, these message are off topic.

Some fun folklore about recent attempts at earthquake predictions.

  In 1973 I attended a meeting conducted by the San Jose, California
  city geologist who was attempting to correlate inches of 
  lost&found advertisements for lost animals in various newspapers 
  with earthquake reports.  Trying to see if cats and dogs left home 
  (got lost) more often before earthquakes.   (current folklore)

  He reported that the powers in U.S.G.S. (United States
  Geological Survey) demanded that at least the following
  (dimly remembered) conditions be satisfied to be a 
  successful earthquake prediction.
     Location   - within 5 kilometers
     Time       - within 6 hours
     Magnitude  - within 0.5 Richter
  and also some other conditions eliminating major earthquake
  aftershocks.  And of course some repeatability and 
  few misses or errors.

  About 1975, there was a quite well publicized investigation
  based from ?Stanford University? ?USGS? asking people to 
  phone if their animal * was currently * acting odd.  
  They were not interest in after the earthquake reports 
  of odd actions.

  I understand the correlation between calls and earthquakes
  was no better than expected statistical coincidence.

More recently
  - observing Radon and/or Helium escaping from water wells
    & also water level in water wells.

  - observing very low frequency magnetic effects

  OH, and the famous Palmdale Bulge/Parkfield event
    -- the earthquake that cerainly did not go as predicted,
       (I believe we have been waiting for it for a decade).


Being a bit of a wild hair, I think that we owe a
strained thanks to the poor souls whose predictions
have been so troubled.   They help remind us that 
even with:
  - wonderfully improving instruments, instrument networks
    and  data networks, 

  - serious studies of earth strains with 
    ever improving equipment, accuracy, ease and 

  - serious studies of earth materials at high
    pressures and stresses

  - the ever improving computer based modeling, displays,
    storage, processing, analyzing, ...

  - ...

we humans seem no closer to useful earthquake predictions.


So, we have heard this guy out,
and understand his game.   Time for a break.

Best Regards
  Ed Thelen

Public Seismic Network Mailing List (PSN-L)

[ Top ] [ Back ] [ Home Page ]

Larry Cochrane <cochrane@..............>