Thanks Dave,

With after thought, I wanted to retract my question about location.  The =
exact epicenter is not a specific point but an area, which might be =
miles!  The general depth might be more precise, but maybe not exact =
either. =20

Realistically, it probably does not matter that much.  You do no have to =
know what cross streets a tornado hits, if it destroyed a town!

Thanks again,
Jerry

-------------------------------------------------------------------------=
-------

From: Dave Nelson=20
Sent: Sunday, November 06, 2011 1:58 PM
To: psnlist@.................
Subject: Re: Earthquake Reports Accuracy

Hey Jerry

I can appreciate depth accurcay may be a bit difficult but I am suprised =
that their=20
epic location is pretty poor. What I really cant understand is why they =
dont seem=20
to use the location data from the local network operation organisations.

This is so apparent back in my home country of New Zealand.  The =
locations and=20
magnitudes bear NO resemblence at all to the data produced by the main =
NZ=20
organisation, the GNS (Geological and Nuclear Sciences).  These guys =
have a=20
good dense network right across NZ and escpecially in the Christchurch =
region=20
over the last 14 months since all those large destructive events.

  The USGS reported magnitudes are often up to 0.5 of a magnitude or =
more out.
And usually its always lower. and up to 10 km of horizontal distance =
out.
a recent aftershock was Mb 5.5 (GNS) reported at Mb 4.7 by USGS  and  =
~10km=20
further east... offshore rather than onshore.... thats a hell of a =
difference !!!

So I think to myself, if they are that far out with their reports for =
regions I have access to real data from. How bad are their reports from =
all those events from=20
the rest of the world ??

cheers
Dave
Sydney




At 10:59 AM 6/11/2011 -0600, you wrote:

  I have a question as to how accurate are the Depth and Location =
reports coming from USGS. =20
  =20
  As I understand it, USGS reports =E2=80=9C5 km=E2=80=9D as a depth =
which could be anywhere from the surface to 26,400 feet down.  I also =
wonder how accurate the epicenter is pinpointed.  Anyone know?
  =20




Thanks Dave,
 
With after thought, I wanted to retract my question about =
location. =20
The exact epicenter is not a specific point but an area, which might be=20
miles!  The general depth might be more precise, but maybe not =
exact=20
either.  
 
Realistically, it probably does not matter that much.  You do =
no have=20
to know what cross streets a tornado hits, if it destroyed a town!
 
Thanks again,
Jerry



From:=20
Dave Nelson 


Sent: Sunday, November 06, 2011 1:58 PM
To: psnlist@.............. 
Subject: Re: Earthquake Reports Accuracy
 
Hey=20
Jerry

I can appreciate depth accurcay may be a bit difficult but =
I am=20
suprised that their 
epic location is pretty poor. What I really cant =

understand is why they dont seem 
to use the location data from the =
local=20
network operation organisations.

This is so apparent back in my =
home=20
country of New Zealand.  The locations and 
magnitudes bear NO=20
resemblence at all to the data produced by the main NZ 
organisation, =
the GNS=20
(Geological and Nuclear Sciences).  These guys have a 
good =
dense=20
network right across NZ and escpecially in the Christchurch region =

over the=20
last 14 months since all those large destructive events.

  =
The USGS=20
reported magnitudes are often up to 0.5 of a magnitude or more =
out.
And=20
usually its always lower. and up to 10 km of horizontal distance=20
out.
a recent aftershock was Mb 5.5 (GNS) reported at Mb 4.7 by =
USGS =20
and  ~10km 
further east... offshore rather than onshore.... =
thats a=20
hell of a difference !!!

So I think to myself, if they are that =
far out=20
with their reports for regions I have access to real data from. How bad =
are=20
their reports from all those events from 
the rest of the world=20
??

cheers
Dave
Sydney




At 10:59 AM =
6/11/2011=20
-0600, you wrote:

I have a question as to how =
accurate are=20
  the Depth and Location reports coming from USGS.  =

 
As=20
  I understand it, USGS reports =E2=80=9C5 km=E2=80=9D as a depth which =
could be anywhere=20
  from the surface to 26,400 feet down.  I also wonder how accurate =
the=20
  epicenter is pinpointed.  Anyone=20
know?
 
Jerry