Special Event

Basic Information


Time of Occurrence (GMT): Wednesday April 28, 1999 at 08:06:16.04 Z
Time of Occurrence (PDT): Wednesday April 28, 1999 at 01:06:16.04 AM
Time of Occurrence (PST): Wednesday April 28, 1999 at 00:06:16.04 AM

Depth (km) 24.01
Magnitude (Mc) 3.8

Location 43.1707N 120.3822W
    92.3 km  SE of Newberry Caldera, Oregon
   123.8 km  SE of Bend, OR
   317.7 km  SE of Portland, OR

This earthquake is located in the southeast corner of the Christmas Lake Valley, Oregon

Name of data file: 99042808061o

This is an automated web page produced after a significant earthquake to give essential information about the earthquake, its aftershocks, and previous earthquake activity in the region. Some of the information here will be updated as aftershocks occur.


Detailed Information and Graphics about the Earthquake

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Foreshocks and Aftershocks

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Earthquake Mechanism

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Moment Tensor Estimates of the Earthquake size may also be available. To see, check at Oregon State U.

Preliminary Strong Motion Information

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