Jerry-

Thanks for the thought, I think I have detected more small quakes 
from off-shore than from small faults on the other side of the San 
Andreas fault that are on-shore.

George

At 02:58 PM 7/18/2010, you wrote:
>Hi George,
>
>I will do a flimsy attempt in answering you question.  Yesterday, I 
>received the August issue of  EARTH magazine with contained a sort 
>article about the Nazca Plate adjacent to Peru.  The article was 
>titled Peruvian Plates Move With and Without Earthquakes.
>
>If I understood the article correctly, it was asking the question as 
>to why a block of the plate might move seismic and another part 
>generate an earthquake.  It pointed out that the majority of the 
>earthquakes occur inland and not actually off shore at the 
>subducting ridge itself.
>
>In humble opinion, that may be because of lubrication from the 
>seawater, which would be less and less at the wedge-shaped plated 
>subducted underneath the South American Plate.  THAT is strictly a 
>guess on my part, as I have NO technical training in geology or seismology!
>
>In regard to your question, I would think the same process "may" be 
>in play there and there may or may not be a direct interaction, who 
>knows.  One might think that jostling a already stressed block might 
>cause it to release; and again it might just lessen the stress.
>
>I'd be interested in others opinions.  Who knows, I might learn 
>something........Naaaaaa.
>
>Regards,
>Jerry
>
>----------
>----- Original Message -----
>From: George Bush
>To: psn-l@..............
>Sent: Sunday, July 18, 2010 4:32 PM
>Subject: What are the implications of a M2.8 quake near the San Andreas fault?
>
>Hello-
>
>This morning we had a M2.8 quake about 4 miles west of us out in the
>ocean and about 5 miles from the San Andreas fault that runs to the
>East of us. It was on a minor fault that runs parallel to the San
>Andreas. The shock knocked my data acquisition computer off-line, but
>was strong enough to jiggle the pen on my drum recorder that also 
>was off line!
>
>I am wondering if the movement of the minor fault will add strain or
>relieve strain on the San Andreas fault (add or decrease the chances
>of the San Andreas fault letting-go).
>
>I would appreciate any thoughts or opinions on this from you PSN folks.
>
>
>George Bush
>Sea Ranch, CA, USA
>38.73775N, 123.48882W
>
>__________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email 
>PSN-L-REQUEST@.............. with
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>See 
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>for more information.



Jerry-


Thanks for the thought, I think I have detected more small quakes from
off-shore than from small faults on the other side of the San Andreas
fault that are on-shore.


George


At 02:58 PM 7/18/2010, you wrote:

Hi George,

 

I will do a flimsy attempt in answering you question.  Yesterday, I
received the August issue of  EARTH magazine with contained a sort
article about the Nazca Plate adjacent to Peru.  The article was
titled Peruvian Plates Move With and Without Earthquakes.

 

If I understood the article correctly, it was asking the question as to
why a block of the plate might move seismic and another part generate an
earthquake.  It pointed out that the majority of the earthquakes
occur inland and not actually off shore at the subducting ridge
itself.

 

In humble opinion, that may be because of lubrication from the seawater,
which would be less and less at the wedge-shaped plated subducted
underneath the South American Plate.  THAT is strictly a guess on my
part, as I have NO technical training in geology or seismology!

 

In regard to your question, I would think the same process
"may" be in play there and there may or may not be a direct
interaction, who knows.  One might think that jostling a already
stressed block might cause it to release; and again it might just lessen
the stress.

 

I'd be interested in others opinions.  Who knows, I might learn
something........Naaaaaa.

 

Regards,

Jerry




----- Original Message ----- 


From: George Bush 


To:
psn-l@.............. 


Sent: Sunday, July 18, 2010 4:32 PM


Subject: What are the implications of a M2.8 quake near the San
Andreas fault?



Hello-



This morning we had a M2.8 quake about 4 miles west of us out in the



ocean and about 5 miles from the San Andreas fault that runs to the



East of us. It was on a minor fault that runs parallel to the San



Andreas. The shock knocked my data acquisition computer off-line, but



was strong enough to jiggle the pen on my drum recorder that also was
off line!



I am wondering if the movement of the minor fault will add strain or



relieve strain on the San Andreas fault (add or decrease the chances



of the San Andreas fault letting-go).



I would appreciate any thoughts or opinions on this from you PSN
folks.





George Bush


Sea Ranch, CA, USA


38.73775N, 123.48882W 



__________________________________________________________



Public Seismic Network Mailing List (PSN-L)



To leave this list email

PSN-L-REQUEST@.............. with 


the body of the message (first line only): unsubscribe


See

http://www.seismicnet.com/maillist.html for more information.




George