## PSN-L Email List Message

Subject: Re: 1x Horizontal geophone, N-S or W-E positioning?
From: Jim ODonnell geophysics.jim@.........
Date: Thu, 6 Jun 2013 12:36:13 -0700

```Hi Tiago- I assume the L15B is a 3-C, 4.5 Hz geophone!  see
http://www.rsuw.daleh.id.au/html/l15b_geophone.html
But you explain it to be a H rather than 2 H's & V.
The terminology used in seismic prospecting is the 2 H's are Radial &
Transverse, and Vertical is V or Z.
So if my site is X, and the Eq's are Eq;  a line from X to Eq is the Radial
(R) direction, and perpendicular to this is the Transverse (T) direction.
If I want to record the S wave I would set the geophone direction (long
axis of the element) perpendicular to R, as the S wave motion is
perpendicular to the line of propagation...You will record the maximum S
wave motion.
Now usually the P wave has more V  motion, so you might not get much P,
from a Horizontal component.

<<<    Jim

Jim O'Donnell BC-Geophysics
Land and Marine Surveys
Geotechnical/Geothermal/Oil & Gas/Mining Applications
Seismic Surveys- Passive Surface Waves, Refraction-Tomography
Ground Penetrating Radar, Resistivity, Magnetic, & VLF-EM Surveys
Geophysics.Jim@......... 702.293.5664 702.281.9081 cell
Boulder City, NV 89005

On Thu, Jun 6, 2013 at 10:40 AM, Tiago A.  wrote:

> Hi.
>
> Most local/regional earthquakes in my location are located in W or E,
> should i point a horizontal geophone (L15B) to N-S or to W-E?
>
>
> If most of the events were located 45 SE from me, should i place the
> horizontal geophone in a 45=BA horizontal position?
>
>
> Using the head (where the connectors are located) of the geophone as
> the reference point.
>
>
> Best Regards,
> Tiago.
> __________________________________________________________
>
> Public Seismic Network Mailing List (PSNLIST)
>
> To leave this list email PSNLIST-REQUEST@.............. with
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Hi Tiago- I assume the L15B is a 3-C, 4.5 Hz geophone=
!=A0 see ht=
tp://www.rsuw.daleh.id.au/html/l15b_geophone.htmlBut you explain it=
to be a H rather than 2=A0H's & V.
The terminology used in seismic prospecting is the 2 H's are Radial &am=
p; Transverse, and Vertical is V or Z.So if my site is X, and the Eq=
9;s are Eq;=A0 a line from X to Eq is the Radial (R) direction, and perpend=
icular to this is the Transverse (T) direction.
If I want to record the S wave I would set the geophone direction (long axi=
s of the element)=A0perpendicular to R, as the S wave motion is=A0 perpendi=
cular=A0to the line of propagation...You will record the maximum S wave mot=
ion.
Now usually the P wave has more V=A0 motion, so you might not get much P, f=
rom a Horizontal component.

<<<=A0=A0=A0 JimJim O'Donnell BC-Geophysics
Land and Marine Surveys
Geotechnical/Geothermal/Oil & Gas/Mining Applications
Seismic Surveys- Passive Surface Waves, Refraction-Tomography
Ground Penetrating Radar, Resistivity, Magnetic, & VLF-EM Surveys
Geophysics.Jim@......... 702.293.5664 702.281.9081 cell

Boulder City, NV 89005

On Thu, Jun 6, 2013 at 10:40 AM, Tiago A. <tiagoagre@.........=
> wrote:
Hi.

Most local/regional earthquakes in my location are located in W or E,
should i point a horizontal geophone (L15B) to N-S or to W-E?

If most of the events were located 45 SE from me, should i place the
horizontal geophone in a 45=BA horizontal position?

Using the head (where the connectors are located) of the geophone as
the reference point.

Best Regards,
Tiago.
__________________________________________________________

Public Seismic Network Mailing List (PSNLIST)

To leave this list email =
PSNLIST-REQUEST@.............. with
the body of the message (first line only): unsubscribe
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