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No. 24: Nov-Dec 1982

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Seismic Ghost Slithers Under California

From 1973 into 1978, instruments monitoring the San Andreas Fault told geophysicists that north-south distances between observing stations along the fault line were contracting. The Pacific Coast was moving north while the rest of North America was heading south! Then, in 1978, the strain eased in the far south of California only to reassert itself in a few weeks. This strange relaxation of strain seemed to propagate slowly across southern California, as seen by other instruments farther north.

As the wave of relaxation moved ponderously along, like a slow flexure of the earth's strata, microearthquakes almost disappeared while the flow of radon from the ground increased, as one might expect. When the strain reappeared, radon flow diminished and a rash of microearthquakes were detected. It took about a year for the strain wave, called a "seismic ghost" by the geophysicists, to flow north from the Imperial Valley into the Los Angeles area.

(Alexander, George; "Quakewatch," Science 82, 3:38, September 1982.)

Comment. Something had to cause this curious disturbance; and where is it located now?

From Science Frontiers #24, NOV-DEC 1982. 1982-2000 William R. Corliss

Science Frontiers Sourcebook Project Reviewed in:


  • "A sourcebook of unexplained phenomena is therefore a valuable addition to a collection of scientific literature. William R. Corliss has provided this in the past with his source books of scientific anomalies in several subjects, and now he has provided it for astronomy. He has done an excellent job of collecting and editing a large amount of material, taken in part from scientific journals and in part from scientific reporting in the popular or semi-scientific press." -- "The Mysterious Universe: A Handbook of Astronomical Anomalies", reviwed by Thomas Gold, Cornell University, in Icarus, vol.41, 1980

  • "An interesting, systematic presentation of unusual weather [..] This book is recommended for a general audience" --"Corliss, William R., Tornados, Dark Days, Anomalous Precipitation, and Related Weather Phenomena, Sourcebook Project, 1983.", revieweed in Choice, September 1983
  • "..the science is necessarily somewhat speculative, but Corliss's symthesis is based on reputable sources." -- "Corliss, William R. (Compiler). Lightning, Auroras, Nocturnal Lights, and Related Luminous Phenomena" reviwed by Joseph M. Moran, Univ. of Wisconsin in Science Books and Films, Sep/Oct 1983

  • "Before opening the book, I set certain standards that a volume which treads into dangerous grounds grounds like this must meet. The author scrupulously met, or even exceeded those standards. Each phenomenon is exhaustively documented, with references to scientific journals [..] and extensive quotations" -- "Book Review: The moon and planets: a catalog of astronomical anomalies", The Sourcebook Project, 1985., Corliss, W. R., Journal of the Royal Astronomical Society of Canada, Vol. 81, no. 1 (1987), p. 24., 02/1987