Re: HOW TO SAVE LIVES IN A QUAKE

Article View: sci.physics

Article #8856

#8856

From: Richard Stead
Date: Thu, 27 Jan 1994 00:06

19 lines
1565 bytes

In article <CARASSO.94Jan25100721@Quaestor.Inference.COM> carasso@Inference.COM (dr. carasso) writes:
>Isn't there a first wave (I think it's called a P wave) that is
>non-forceful?  How much before the S wave is the P wave generated?

It is generated simultaneously with the S wave.  Only Rayleigh and Love waves
are delayed in generation, since they require interaction with the surface.

>What speed does it travel at?

About sqrt(3) times the S wave speed.  It's exactly sqrt(3) for a Poisson
solid.  While earth materials aren't perfectly Poisson, they're generally
very close.

-- 
Richard Stead
Center for Seismic Studies
Arlington, VA
stead@seismo.css.gov

Technical Details

Message-ID: <2i70i7$ec7@seismo.CSS.GOV>

Path:

arc1-ca.pugleaf.net!gmd.de!xlink.net!news.ppp.de!lutzifer!news.rrz.uni-hamburg.de!unibwh.unibw-hamburg.de!Germany.EU.net!EU.net!howland.reston.ans.net!usenet.ins.cwru.edu!ukma!rsg1.er.usgs.gov!seismo!stead

References:

<CARASSO.94Jan24112935@Quaestor.Inference.COM> <2i1out$7n7@seismo.CSS.GOV> <CARASSO.94Jan25100721@Quaestor.Inference.COM>

Show Full Headers

Complete Article Headers

X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 111c3f,7ca4767b95098142
X-Google-Attributes: gid111c3f,public
X-Google-Thread: 10b271,7ca4767b95098142
X-Google-Attributes: gid10b271,public
X-Google-ArrivalTime: 1994-01-28 00:33:43 PST
Path: arc1-ca.pugleaf.net!gmd.de!xlink.net!news.ppp.de!lutzifer!news.rrz.uni-hamburg.de!unibwh.unibw-hamburg.de!Germany.EU.net!EU.net!howland.reston.ans.net!usenet.ins.cwru.edu!ukma!rsg1.er.usgs.gov!seismo!stead
From: stead@seismo.CSS.GOV (Richard Stead)
Newsgroups: sci.physics,ca.earthquakes
Subject: Re: HOW TO SAVE LIVES IN A QUAKE
Date: 27 Jan 1994 00:06:31 GMT
Organization: Center for Seismic Studies, Arlington, VA
Lines: 19
Message-ID: <2i70i7$ec7@seismo.CSS.GOV>
References: <CARASSO.94Jan24112935@Quaestor.Inference.COM> <2i1out$7n7@seismo.CSS.GOV> <CARASSO.94Jan25100721@Quaestor.Inference.COM>
NNTP-Posting-Host: skadi.css.gov

Reply to Parent Message