Mark, thank you so much for your reply.  I loved the TV interviews and 
photographs.  It is almost like being there!  It is one thing to sense and 
record a distant EQ, but to see pictures and reports really adds to the 
overall experience.  we are all relived that there were no serious injuries.

Thanks again,
Jerry

  ----- Original Message ----- 
  From: Mark Robinson
  To: psnlist@..............
  Sent: Sunday, September 05, 2010 5:51 PM
  Subject: Re: Now I Am Confused - AGAIN


  NZ's geological service has a page up on the quake at

  > 
http://www.geonet.org.nz/news/article-sep-4-2010-christchurch-earthquake.html

  It includes maps and photographs showing the surface rupture which is 
variously
  reported as 13 and 22km in length. Lateral displacements up to 4m have 
been
  measured and are evident in the photographs.

  The main event report is at

  http://www.geonet.org.nz/earthquake/quakes/3366146g.html

  while the following link provides felt reports from the general public as 
well
  as measured peak ground accelerations and velocities

  http://www.geonet.org.nz/earthquake/quakes/3366146g-shaking.html

  There have been in excess of 80 significant aftershocks (>mag3) since the 
main
  event and the rest of the country is showing high levels of background 
activity
  with significant volcanic tremor in the volcanic plateau of the North 
Island
  and unusual levels of seismic noise across the country.

  Eigenmode activity was observed sporadically over the week leading up to 
the
  main quake.

  The damage has been compounded by heavy rain and strong winds.

  The army has been deployed to enforce a cordon around the Christchurch CBD
  while isolated disorder is being reported as people try to access 
supermarkets
  and pharmacy services.

  Official instructions to not attend the hospitals except in cases of 
serious
  emergency leave residents in a Catch-22 as doctors and other small 
businesses
  are instructed not to open until their premises have been inspected by
  structural engineers.

  There is considerable damage to the water and sewerage systems with 20% of
  Christchurch having no water supply. This will take a long time to repair.

  All schools are closed until at least Wednesday.

  A selection of local media

  http://www.nzherald.co.nz/?c_id=1502981
  http://www.scoop.co.nz/
  http://www.stuff.co.nz/
  http://tvnz.co.nz/national-news
  http://www.3news.co.nz/
  http://www.radionz.co.nz/news


  On 06/09/10 09:20, GPayton wrote:
  > Dave, I am so glad that you answered, being from NZ. I was hoping that
  > you would.
  > When the quake occurred, I looked at Google Earth and it appeared that
  > the area was mountainous, but that software can be misleading sometimes.
  > Thank you for the input. I suspect the ground acted like a "wet sponge"
  > then.
  > Best regards,
  > Jerry
  >     ----- Original Message -----
  >     *From:* Dave Nelson 
  >     *To:* psnlist@.............. 
  >     *Sent:* Sunday, September 05, 2010 4:04 PM
  >     *Subject:* Re: Now I Am Confused - AGAIN
  >
  >     Hey Jerry,
  >     its a pretty complex subject, and the amount of shaking
  >     and liquefaction
  >     is proportion to a number of things, including....
  >     distance from the quake .... attenuation of the waves
  >     magnitude of the quake .... size affects the period of severe 
shaking
  >     soil type .... soft, hard, gravels etc etc
  >
  >     I know Christchurch city very well, having worked there, visited
  >     there many
  >     times
  >     over the years and my 2 kids (early 20's) still live there and went
  >     through
  >     this quake.
  >     A large portion of Christchurch is basically built on a swamp, it is
  >     very
  >     soft wet soils
  >     being an estuary area of 2 rivers.
  >     When I worked for telecom there and were doing cable laying, you
  >     only had
  >     to dig
  >     down a couple of feet and you holes/trenches started to slowly fill
  >     with water.
  >
  >     So the 3 factors above and others not mentioned all play a part in
  >     how much
  >     damage is going to occur.
  >     Magnitude therefore period of intense shaking is very signif. as
  >     they found
  >     out in that
  >     huge quake in mexico in 1985 the M8.1 was a long way from the city, 
but
  >     the combination of the alluvial basin the city sat on, the period of
  >     shaking are what contributed to the horrific numbers of deaths and
  >     severe
  >     damage (not to mention the crappy building construction)
  >     REMEMBER ... New Zealand is pretty anal about earthquake 
prepardness...
  >     very strict building codes etc etc
  >
  >     cheers
  >     Dave Nelson
  >     Sydney
  >     Ex New Zealand
  >
  >     At 12:21 AM 6/09/2010, you wrote:
  >      >I was just reading an article about damages from the recent New
  >     Zealand
  >      >EQ. I saw the following quote which seemed to be a contradiction
  >     to the
  >      >California EQ where soft ground cause liquefaction of the ground.
  >      >
  >      >The quote is as follows: "Euan Smith, professor of Geophysics at
  >     Victoria
  >      >University, speculated that the very soft soils of Christchurch
  >     had "acted
  >      >like a shock absorber over a short period ... doing less damage to
  >     smaller
  >      >buildings."
  >      >
  >      >Is this just a matter of less water content in the soils?
  >      >
  >      >Jerry

  __________________________________________________________

  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.







Mark, thank you so much for your reply.  I loved the TV =
interviews and=20
photographs.  It is almost like being there!  It is one thing =
to sense=20
and record a distant EQ, but to see pictures and reports really adds to =
the=20
overall experience.  we are all relived that there were no serious=20
injuries.
 
Thanks again,
Jerry 
 

  
----- Original Message ----- 
  From:=20
  Mark Robinson 
  
To: psnlist@.............. =

  
Sent: Sunday, September 05, =
2010 5:51=20
  PM
  
Subject: Re: Now I Am Confused =
-=20
  AGAIN
  

NZ's geological service has a page up on the quake=20
  at

> http://www.geonet.org.nz/news/article-sep-4-2010-christchur=
ch-earthquake.html

It=20
  includes maps and photographs showing the surface rupture which is =
variously=20
  
reported as 13 and 22km in length. Lateral displacements up to 4m =
have=20
  been 
measured and are evident in the photographs.

The main =
event=20
  report is at

http://=
www.geonet.org.nz/earthquake/quakes/3366146g.html

while=20
  the following link provides felt reports from the general public as =
well=20
  
as measured peak ground accelerations and velocities

http://www.geonet.org.nz/earthquake/quakes/3366146g-shaking.html
=

There=20
  have been in excess of 80 significant aftershocks (>mag3) since the =
main=20
  
event and the rest of the country is showing high levels of =
background=20
  activity 
with significant volcanic tremor in the volcanic plateau =
of the=20
  North Island 
and unusual levels of seismic noise across the=20
  country.

Eigenmode activity was observed sporadically over the =
week=20
  leading up to the 
main quake.

The damage has been =
compounded by=20
  heavy rain and strong winds.

The army has been deployed to =
enforce a=20
  cordon around the Christchurch CBD 
while isolated disorder is =
being=20
  reported as people try to access supermarkets 
and pharmacy=20
  services.

Official instructions to not attend the hospitals =
except in=20
  cases of serious 
emergency leave residents in a Catch-22 as =
doctors and=20
  other small businesses 
are instructed not to open until their =
premises=20
  have been inspected by 
structural engineers.

There is =
considerable=20
  damage to the water and sewerage systems with 20% of 
Christchurch =
having=20
  no water supply. This will take a long time to repair.

All =
schools are=20
  closed until at least Wednesday.

A selection of local =
media

http://www.nzherald.co=
..nz/?c_id=3D1502981
http://www.scoop.co.nz/
http://www.stuff.co.nz/
http://tvnz.co.nz/national-news<=
/A>
http://www.3news.co.nz/
http://www.radionz.co.nz/news<=
BR>

On=20
  06/09/10 09:20, GPayton wrote:
> Dave, I am so glad that you =
answered,=20
  being from NZ. I was hoping that
> you would.
> When the =
quake=20
  occurred, I looked at Google Earth and it appeared that
> the =
area was=20
  mountainous, but that software can be misleading sometimes.
> =
Thank you=20
  for the input. I suspect the ground acted like a "wet sponge"
>=20
  then.
> Best regards,
> =
Jerry
>    =20
  ----- Original Message -----
>     *From:* =
Dave=20
  Nelson <mailto:dave.nelson@...........
om.au>
>    =20
  *To:* psnlist@..............=20
  <mailto:psnlist@..............&=
gt;
>    =20
  *Sent:* Sunday, September 05, 2010 4:04 =
PM
>    =20
  *Subject:* Re: Now I Am Confused -=20
  AGAIN
>
>     Hey=20
  Jerry,
>     its a pretty complex subject, =
and the=20
  amount of shaking
>     and=20
  liquefaction
>     is proportion to a number =
of=20
  things, including....
>     distance from =
the quake=20
  .... attenuation of the waves
>     =
magnitude of the=20
  quake .... size affects the period of severe=20
  shaking
>     soil type .... soft, hard, =
gravels etc=20
  etc
>
>     I know Christchurch city =
very=20
  well, having worked there, visited
>     =
there=20
  many
>     =
times
>    =20
  over the years and my 2 kids (early 20's) still live there and=20
  went
>     =
through
>    =20
  this quake.
>     A large portion of =
Christchurch is=20
  basically built on a swamp, it is
>    =20
  very
>     soft wet=20
  soils
>     being an estuary area of 2=20
  rivers.
>     When I worked for telecom =
there and=20
  were doing cable laying, you
>     only=20
  had
>     to =
dig
>    =20
  down a couple of feet and you holes/trenches started to slowly=20
  fill
>     with=20
  water.
>
>     So the 3 factors above =
and=20
  others not mentioned all play a part =
in
>     how=20
  much
>     damage is going to=20
  occur.
>     Magnitude therefore period of =
intense=20
  shaking is very signif. as
>     they=20
  found
>     out in=20
  that
>     huge quake in mexico in 1985 the =
M8.1 was=20
  a long way from the city, but
>     the =
combination=20
  of the alluvial basin the city sat on, the period=20
  of
>     shaking are what contributed to the =

  horrific numbers of deaths and
>    =20
  severe
>     damage (not to mention the =
crappy=20
  building construction)
>     REMEMBER ... =
New=20
  Zealand is pretty anal about earthquake=20
  prepardness...
>     very strict building =
codes etc=20
  etc
>
>    =20
  cheers
>     Dave=20
  Nelson
>     =
Sydney
>    =20
  Ex New Zealand
>
>     At 12:21 AM =
6/09/2010,=20
  you wrote:
>      >I was just =
reading an=20
  article about damages from the recent =
New
>    =20
  Zealand
>      >EQ. I saw the =
following=20
  quote which seemed to be a =
contradiction
>     to=20
  the
>      >California EQ where soft =
ground=20
  cause liquefaction of the =
ground.
>     =20
  >
>      >The quote is as =
follows: "Euan=20
  Smith, professor of Geophysics at
>    =20
  Victoria
>      >University, =
speculated that=20
  the very soft soils of Christchurch
>     =
had=20
  "acted
>      >like a shock absorber =
over a=20
  short period ... doing less damage to
>    =20
  smaller
>     =20
  >buildings."
>     =20
  >
>      >Is this just a matter =
of less=20
  water content in the soils?
>     =20
  >
>     =20
  =
>Jerry

________________________________________________________=
__

Public=20
  Seismic Network Mailing List (PSNLIST)

To leave this list email =
PSNLIST-REQUEST@SEISMICNET=
..COM=20
  with 
the body of the message (first line only): unsubscribe
See =
http://www.seismicnet.co=
m/maillist.html=20
  for more information.