Wildilocks’ presence in New Zealand is approaching a year now, and it’s been a crazy busy one with moving our Perth salon in October/November and then running Euchronia in December last year in Melbourne, too! 2011 got off to a crazy start for Australia, with floods, cyclones and the ever-present bushfires, it’s been a hard slog for many in Oz over the past couple of months, let alone the rest of the world. New Zealand had been relatively unscathed in comparison: until two days ago. I just want to reassure those of you who may not know New Zealand well, Wellington where we are is a long way from Christchurch, but we have friends down there (and just about everyone in New Zealand seems to know someone in Christchurch) and wish to send all the love we can to the people suffering there right now. This is the first time ever that New Zealand has declared a national state of emergency – yes, it’s bad. Very bad.
A friend of mine and Regional Burning Man rep, Mark Stirling, sent a message out last night with some useful information regarding the quake, which with his permission I’d like to share with those of you who may have questions, as his message answers a lot.
“At this time I would normally write a note to you all about the great event of Kiwiburn, and the excitement of an upcoming Decom. While this is indeed worthwhile talking and thinking about, I thought it appropriate to instead take off my “Kiwiburn regional hat ” and briefly put on my “daytime job hat” to talk about our devastating Christchurch earthquake of yesterday (I am an earthquake scientist at GNS Science). Many of you have been emailing and texting me with questions about the earthquake, and those of you overseas have also been sending your concerned thoughts (thank you very much). Here are answers to some common questions that have come up:
– The earthquake was an aftershock of the Sept 2010 magnitude 7.1 earthquake. It is typical for the largest aftershock to be about 1 magnitude unit less than the mainshock, so yesterdays M6.3 event was about the right size for the largest aftershock. The quake was much closer to Christchurch, and shallower than the Sept 2010 quake, which is why it caused so much damage. We know it is an aftershock as it is within the zone of aftershocks from the 2010 quake, and it has happened less than a year after the mainshock ( a year is short in seismology terms). We expect aftershocks to continue for some time yet, but don’t have any numbers on this as yet.
– Anything you hear about the Canterbury quakes being the start of an “earthquake cascade” up and down NZ should be taken with less than a grain of salt. There are no statistically valid findings that show this is going to happen. Any kind of earthquake forecast or prediction methodology has to be thoroughly reviewed and tested many times over before it can be taken seriously. Just remember though, that NZ is an active country in nearly every way, and we should be prepared for anything. Earthquakes, floods, landslides, volcanoes and tsunamis. Find out more about where you live.
– In terms of our earthquake hazard estimates for the country (my main field of work when I am not overseas!), the strong earthquake ground shaking in yesterdays quake was equivalent to what we would expect for CHCH on average about once every 10000 years. Unfortunately this very rare strong shaking happened in our lifetime, and in fact in our civilisation! There is plenty of evidence as to the rarity of this shaking in the CHCH area. Not only the 100-plus year old CHCH Cathedral received the worst damage ever, but features like the old abandoned seacliffs in the Sumner/Redcliffs area have been majorly damaged for the first time since they were formed thousands of years ago.
– The liquefaction mainly happens where sandy/muddy materials have a high water table, and the shaking causes the materials to lose their internal tension and turn into flowing, bubbling liquid. Much of CHCH is on liquefiable materials, particularly in the eastern parts of the city.”
If you’d like to help, there are a number of ways to do so from outside New Zealand, where I imagine the majority if you reading this are. Links are below:
For up to date information see:
Civil Defence information. Very informative.
Christchurch, our thoughts are with you.