It is obvious the waves are being somewhat distorted but the question
which I have is will the waves be magnified or suppressed by the buildings response?

Just last night I saw on tv this huge seismic damper inside this foreign building
in the form of a giant massive ball supported by shock absorbers and
thought this device might make a decent seismic receiver
by either looking at absolute motion or pressures within the
damping system itself.

Regards,
geoff


-----Original Message----- 
From: Dave Nelson 
Sent: Monday, January 24, 2011 8:20 PM 
To: psnlist@.............. 
Subject: Re: Recording earthquakes from 3rd floor 


The problem with elevating the seismometer is that the main thing you are
recording is the buildings' response to the seismic waves rather than the 
seismic
waves themselves.

   The further up in the building you are the more the building 
sways,  even for distance events.

Dave




At 06:43 AM 25/01/2011, you wrote:
>I'm on the third floor, and as you can see by the pictures on my website, 
>the result is that you'll see all the big earthquakes easily.
>
>http://www.brasswings.com/seis.html
>
>But of course there is a huge amount of background noise.
>Wind is the biggest issue.   Windy days can block out pretty much everything.
>You'll also find that the floor probably isnt solid enough to rest a 
>seismometer on.     The weight of a human is enough to register full scale 
>deflection as the floor sags, when you move from one side of the room to 
>the other.
>The best I could do is to lift the sensor box off the floor and press it 
>up against the wall (in a corner) with the weight of some bricks.
>If you've got the ability to measure it (with an inclinometer), you'll 
>also see how much the building sways backward and forward through the 
>course of the day and it heats up and cools down.
>
>But as you say, its worth a try anyway.   You might have a more solid 
>building than mine.
>
>
>
>
>Glenn
>
>__________________________________________________________
>
>Public Seismic Network Mailing List (PSNLIST)
>
>To leave this list email PSNLIST-REQUEST@.............. with the body of 
>the message (first line only): unsubscribe
>See http://www.seismicnet.com/maillist.html for more information.

__________________________________________________________

Public Seismic Network Mailing List (PSNLIST)

To leave this list email PSNLIST-REQUEST@.............. with 
the body of the message (first line only): unsubscribe
See http://www.seismicnet.com/maillist.html for more information.
__________________________________________________________

Public Seismic Network Mailing List (PSNLIST)

To leave this list email PSNLIST-REQUEST@.............. with 
the body of the message (first line only): unsubscribe
See http://www.seismicnet.com/maillist.html for more information.