Revision History for USGS Open-File Report 93-309

  Kent A. Fogleman, John C. Lahr, Christopher D. Stephens 
  and Robert A. Page

  Earthquake Locations Determined by the Southern Alaska 
  Seismograph Network for October 1971 through May 1989


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  Version 1.1 posted online at 
  http://pubs.usgs.gov/of/1993/0309/
  April 25, 2012

  The original document was revised to clarify, amplify or 
  correct parts of the report, to add events from time 
  intervals not previously reported, and to provide summary 
  and phase data files.  

  Included in the original report is a brief summary of the 
  seismicity of southern Alaska as understood in 1993.  
  That summary has not been updated to incorporate the 
  findings of more recent investigations.  For a more 
  current overview, see the papers in the recent volume, 
  Active Tectonics and Seismic Potential of Alaska 
  (Freymueller, J.T, Haeussler, P.J., Wesson, R. and 
  Ekstrom,G. eds., 2008, AGU Geophysical Monograph 179, 
  American Geophysical Union, Washington, D.C.)

  Additions to Version 1.0
     Data package containing folders:
          Summary data for all located events, 1971-1989
          Event phase data for located events by month/year
          Locations and arrival time data for Trans-Alaska 
               Crustal Transect explosions, 1984 & 1985
          HYPOELLIPSE control files


  Initial release in paper form
  June 1993

  The original document describes the instrumentation and 
  evolution of the U.S. Geological Survey's regional 
  seismograph network in southern Alaska, provides tables 
  of seismograph stations used and located earthquakes of 
  magnitude 4.0 or larger from October 1971 through May 
  1989, reviews the methods to determine hypocenters and 
  magnitudes, and discusses the completeness of the catalog 
  and the accuracy of the computed hypocenters.  The 
  document stated that summary and phase data for more than 
  50,000 located events recorded by the network as well the 
  location program and control files were to be available 
  on compact disk as part of the proceedings of a 
  conference.  The proceedings were never completed.

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