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Magnitude 6.9 RAT ISLANDS, ALEUTIAN ISLANDS, ALASKA

2003 June 23 12:12:36 UTC

Preliminary Earthquake Report

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

RAT ISLANDS, ALEUTIAN ISLANDS

03/06/23 12:12:35 UTC
Epicenter 51.58N 176.67E

BROADBAND SOURCE PARAMETERS
 Energy Magnitude:
  Me                         6.8
 Radiated Energy:
  Es               3.4*10**14 Nm
  No. of sta: 21  Focal mech.  F
 Broadband Depth:        20.0 km
 Broadband Fault Plane Solution:
 NP1:Strike= 70 Dip=80 Slip=  80
 NP2:       295     14       135
 Principal Axes:
  T              Plg=54  Azm=328
  P                  34      169
 COMMENT:  Two events about 2 seconds apart. Depth from synthetics of broadband       
  displacement seismograms based on larger second event.

Explanation of Parameters
Latest USGS Energy Solutions
Source Parameter Search

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