Thomas Dick wrote:
> You're right John, I am NOT close to 180 degree from the epicenter. I 
> have put the data in over ten times. Early on, I even reverse the 177 to 
> a positive number to try and get it to show phases think it was an error 
> on the post. The travel time table shows 107 degrees and 11896 km. I 
> have made mistakes before...particularly before two cups of morning 
> coffee but not this time.

"The shadow zone is the area of the earth from angular distances of 104 to 140 
degrees from a given earthquake that does not receive any direct P waves."

http://earthquake.usgs.gov/learning/glossary.php?termID=170&alpha=S

> ----- Original Message ----- From: "John Lahr" 
>> Check that you have the correct lat and lon for the Fiji event.  It 
>> was not 180 degrees away from the mid west.
>> For computed distances, see this USGS page:
>> http://neic.usgs.gov/neis/eq_depot/2007/eq_071209_ksak/neic_ksak_t.html
>> This page includes two seismograms from Oregon:
>> http://jclahr.com/science/psn/as1/figi07/index.html
>> At 02:03 PM 12/9/2007, you wrote:
>>> I don't think this is so simple. May be a quark in the software in 
>>> reference to the location here in midwest -- too close to 180 
>>> degrees. There is no doubt that I got a good record. The arrival of 
>>> Pdiff appears the same as on the local university helicorder and if I 
>>> try to place Pdiff and S manually, I can get phases to come in (if I 
>>> use the locate feature in conjunction) but if I move S  one way or 
>>> the other just a little everything disappears..I even processed a 2.4 
>>> locally about twenty minutes before with no trouble. So Larry's 
>>> program works fine!
>>> ----- Original Message ----- From: "Mark Robinson" 
>>> 
>>> To: 
>>> Sent: Sunday, December 09, 2007 3:48 PM
>>> Subject: Re: Fiji area quake
>>>
>>>
>>>> Thomas Dick wrote:
>>>>> Is there anything wrong with the time or location for the 7.8 quake 
>>>>> today? I'm not able to put the data into Winquake and get phases. I 
>>>>> certaining register the quake in the time frame that it was suppose 
>>>>> to arrive.
>>>>
>>>> I felt that quake here at almost 1800km distance and can confirm the 
>>>> time.
>>>>
>>>> Looking at the traces I think it would be difficult to characterise 
>>>> the event as instantaneous.
>>>>
>>>> I was particularly struck by the huge very long period (~30min) 
>>>> waves shown on the Kermadec LISS seismograph shortly after the event 
>>>> (before they were obliterated by traces from subsequent hours).


-- 
Mark Robinson
-------------
10 Dec 1953 Winston Churchill wins Nobel prize for literature.
10 Dec 1965 Annie Crummer born.
10 Dec 1972 Split Enz play their debut at Auckland Wynyard Tavern.
__________________________________________________________

Public Seismic Network Mailing List (PSN-L)