Earthquake in Christchurch!

Auckland Council building control manager Bob de Leur said that unlike Christchurch, much of Auckland's CBD consisted of reinforced concrete structures that were built since the 1970s, when stricter building codes were introduced.

Would nt they have basing the 22 figure on eye witness/cathedral staff accounts?

somethings weird...I guess its just original reporting, but its bizzare how inaccurate that reporting was

The upheaval wrought by the 22 February earthquake in Christchurch, NZ, is illustrated in new radar imagery.

The Magnitude 6.3 tremor killed more than 160 people and shattered a city already reeling from a previous seismic event in September.

Data from the Japanese Alos spacecraft has been used to map the way the ground deformed during the most recent quake.

What scientists need to know now is the nature of any "seismic gap" between the two; that is, a segment of fault which was not broken in either tremor but which may have been loaded with additional strain because of both those events

interesting seeing this doco from 15 years ago talking about liquefaction after 'the big one' in Chch

This video excerpt from a 1996 Inside New Zealand special on earthquakes has been doing the rounds on Twitter today. While interesting viewing to those who haven’t seen it, I think a couple of things should be kept in mind.
First, I think people should be very careful not to make assumptions and draw conclusions about what happen in the September 4th and subsequent catastrophic February 22nd earthquakes, before any sort of factual information has been gathered on the cause of the destruction around the city, especially with regards to the CTV and Pine Gould Corporation buildings.

Second, no one should be particularly surprised at the information revealed. I vividly remember seeing this when it screened in 1996. I remember the focus on the high susceptibility to liquefaction particularly in the east of the city. I remember the claim of an earthquake potential of magnitude 8 on the Alpine Fault. The risks have long been known, and still exist today. The conclusion some are coming to from watching this is, given these risks were known, things should have been done totally differently. Hindsight is indeed 20/20.

The reality is there were processes in place to mitigate these risks. Strengthening work saved many buildings and lives in the city. New construction and infrastructure work was being done to a standard which would stand up to these reasonable known risks.

So now what? We still face the same risks we did in 1996 with regards to large earthquakes on faults relatively close to the city. What do we do differently? Do we go out and rip down every building which doesn’t meet 100% code within two years? Too slow? Ok, lets reduce that to a year. Now what if the Alpine Fault went tomorrow? People would be up in arms because things still moved too slowly. What if the city was retrofitted in a year, and the Alpine Fault didn’t go for another 200 years? People would see the haste of the massive cost outlay as unnecessary and pressured.

Risk is inherently hard to quantify. I sure as hell didn’t expect to be woken at 4:35 AM on the 4th of September to a massive earthquake, nor see the things I saw on the 22nd of February. You can only do your best with the information you have at the time, and work within the practicalities you face.