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Magnitude 8.3 HOKKAIDO, JAPAN REGION

2003 September 25 19:50:06 UTC

Preliminary Earthquake Report

U.S. Geological Survey, National Earthquake Information Center
World Data Center for Seismology, Denver

HOKKAIDO, JAPAN REGION

03/09/25 19:50:08 UTC
Epicenter 42.17N 143.72E

BROADBAND SOURCE PARAMETERS
 Energy Magnitude:
  Me                         7.9
 Radiated Energy:
  Es               1.7*10**16 Nm
  No. of sta: 18  Focal mech.  F
 Broadband Depth:        27.0 km
 COMMENT:  Complex earthquake observed on broadband displacement
  seismograms, with at least two larger events occurring several
  seconds after the onset. Depth from synthetics of broadband
  displacement seismograms based on second event.              

Explanation of Parameters
Latest USGS Energy Solutions
Source Parameter Search

For more information, contact George Choy, choy@usgs.gov