Subject: [SLR-Mail] No. 785: Status on the movement of Arequipa
From: Van Husson, ILRS Central Bureau <###FROM###>

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SLR Electronic Mail          2001-07-18 18:55:00 UTC           Message No. 785 
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Author: Van Husson, ILRS Central Bureau
Subject: Status on the movement of Arequipa


Dear Colleagues,

A massive earthquake (8.4) struck beneath southern Peru at 20:33 GMT 
on June 23, 2001. The earth quake was 175 km West of Arequipa, Peru. 
There have been a number of large aftershocks with the largest (7.6)
being on July 7th at 9:38 GMT, which was 110 km south-southwest of
Arequipa. (Check out the graphics below:)

http://earthquake.usgs.gov/activity/latest/eq_01_06_23/index.html
 
http://earthquake.usgs.gov/activity/latest/eq_01_07_07/index.html


The June 23 shock originated just southeast of the source of a
magnitude 7.7 earthquake that occurred in 1996, and it appears to
have involved rupture of part of the plate-boundary segment that
producedan earthquake of magnitude approximately 9.0 in 1868. The
1868 earthquake was destructive in towns that were heavily damaged
in the June 23rd earthquake. The 1868 earthquake produced a tsunami
that killed hundredsof people along the South American coast. The
1868 tsunami also caused damage in Hawaii and alarm in Japan.
The initial onset on June 23rd consists of two events separated
by about 6 seconds. It was followed by at least one larger complex
event occurring about 40 seconds later. (Excerpt from USGS)


Arequipa&#180;s (Station 7403) first pass after the June 23rd quake was 
July 3rd (more than a week later). Below is a listing of LAGEOS
passes post quake (as of July 17th).

     7403 03-jul-2001 18:36    LAGEOS   
     7403 04-jul-2001 05:05    LAGEOS-2 
     7403 05-jul-2001 02:59    LAGEOS-2 
     7403 05-jul-2001 05:33    LAGEOS   
     7403 09-jul-2001 03:31    LAGEOS-2 
     7403 09-jul-2001 03:45    LAGEOS   
     7403 09-jul-2001 07:05    LAGEOS   
     7403 10-jul-2001 01:42    LAGEOS-2 
     7403 10-jul-2001 05:46    LAGEOS   
     7403 10-jul-2001 06:21    LAGEOS   
     7403 10-jul-2001 23:43    LAGEOS-2 
     7403 11-jul-2001 00:07    LAGEOS-2 
     7403 11-jul-2001 03:53    LAGEOS-2 
     7403 11-jul-2001 04:21    LAGEOS   
     7403 12-jul-2001 01:43    LAGEOS-2 
     7403 12-jul-2001 03:17    LAGEOS   
     7403 13-jul-2001 03:55    LAGEOS-2 
     7403 13-jul-2001 04:11    LAGEOS-2 
     7403 13-jul-2001 05:07    LAGEOS   
     7403 16-jul-2001 02:09    LAGEOS-2 
     7403 16-jul-2001 02:17    LAGEOS-2 
     7403 16-jul-2001 04:36    LAGEOS   
     7403 17-jul-2001 00:19    LAGEOS-2 
     7403 17-jul-2001 03:33    LAGEOS   


RESULTS FROM NERC SLR (7403) ANALYSIS 

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