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

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