You can check out the GeoNet recent earthquakes webpage to see if there have been any earthquakes today and where they were centred. The place where a fault breaks causing an earthquake is called the focus, and the point directly above is called the epicentre. Why do you think it would be important to know where an earthquake's epicentre is?
Image: Public Domain. Earthquakes can cause serious damage, especially to old buildings like this one in central Christchurch. Why do you think the Canterbury earthquakes of caused so much damage in Christchurch? The energy released by a fault movement radiates outwards as seismic waves. There are two types of seismic waves; P-waves and S-waves. What are the differences between these two wave types?
Image: GNS Science. Earthquakes affect different ground types differently. In areas of soft, wet ground such as the eastern suburbs of Christchurch liquefaction can occur. What is liquefaction and what damage can it cause?
Earthquakes can cause land to move and sink, damaging houses. How do you think this damage could be minimised? Skip to main content. Earthquakes in New Zealand. Contents: Standard. Next» Landslides in New Zealand. Easy Version. This quake is thought to have caused damage mainly because it was so shallow, with a secondary emphasis on liquefaction.
The occasional GNS scientists who are making statements on local TV are also pointing out that soil-surface acceleration in this quake was approximately twice as high as in the 7. The non-zero death toll in this one has been largely put down to the fact that people were at work in the central city where the older buildings are for this one, in contrast to the September quake which struck in the small hours of the morning while everyone was out their comparatively light, wooden homes in the suburbs.
It's not just the magnitude. This one happened close to the surface, which made it so damaging. As others have said, the building standards in NZ are very high with specific earthquake-related elements. I may be repeating, but there are several things to remember:. I getting the impression the liquefaction occurred in areas it didn't before?
The Sep 4th event occurred in the wee hours of the morning, when all but those living in inner city apartments would be in the suburbs at home. Eric, the older buildings would have been strengthened or should have - it's a requirement. Some older buildings from some time ago were pulled down as the cost of strengthening didn't figure well with the cost of replacing -at least this is my understanding.
A problem here will simply be that this latest event will no doubt have conflicted with repair work still being underway. Greg, You should be able to locate an USGS Pacific map featuring the "ring of fire" as it's nicknamed showing the earthquakes. It says a lot in an image. Haven't time to track it down, sorry. Forgot to add, there's more on the census and the earthquake at sciblogs.
And to say "thanks, Greg"! Thanks for the insights on the ChCh NZ building situation. Lots of earthquake proofing in those two cities, but there would be a lot of damage anyway. Grant, it is also interesting to see how emergency systems and communications systems fail or not. You'd have to see to get what I mean. It's a case of the data presented one way telling it's own story. Re: cell phones. I don't know what happened in NYC, but a problem for us is that if the power goes out in a quake as it does in large ones the cell towers switch over to batteries, which only last for so long.
The telecomm people then try to bring in generators to cover them until the power is back up. Heavy usage draws on the batteries, and phone calls as opposed to texts tend to occupy the capacity.
Not an expert, just what I've picked up; it's the second time around on this for Chch. About reading about the earthquake at sciblogs, you're most welcome to read my post on it, but I think realistically you'd do better to look at my colleagues efforts. Mine is a stream of snippets and links as the events unfolded and somewhat aimed at locals who know the places. Christchurch is my hometown, btw; I now live in Dunedin. The only effective way of detecting people under the rubble - it's infrared camera of a military helicopter.
Quality infrared cameras mounted also on fighters, but the possibility of detection of small objects is limited by the speed of aircraft.
As the geologists investigate the earthquake details are emerging for why it has been so devastating. The Building Code in New Zealand is for high quality surviable construction. But he said the earthquake hit central Christchurch with more than twice the intensity of the larger magnitude 7. He said Tuesday's quake was of a force statistically unlikely to occur more than once in years and produced ground acceleration 1.
Hello from the States. Watching a broadcast about the evolutionary origins of the Kiwi and geological history of NZ brought me to this site, where I was pleasantly surprised to read that yours is a region populated by HSs that are overwhelmingly not infected by those I regard as the "willfully ignorant" free educational opps here are overwhelmingly numerous yet most citizens are far too intellectually lazy to embrace, take advantage of or sustain.
Now, I find myself wondering, how difficult it is to establish NZ residency? Best regards! It's so evident with volcanoes and earthquakes that we are just inhabiting the surface of so much planetary greatness happening underneath.
I don't care how large an island seems to be when you are standing in the middle of it.. Hawaii It is still an Island!! I often wonder over the millenia how many Islands that at one time were huge and habitable are now hidden under the waves somewhere. With that many earthquakes happening in Christchurch, I would be relocating Wouldn't you?? Sorry but people are so stupid when it comes to religion its just what you believe and if you have faith.
I don't believe in god but there is a hire power but it not from this earth. If you think we are the only one in this big space of the galaxy or universe your just stupid and you have a shallow mind.
By gregladen on February 22, Here's New Zealand: The most recent earthquake there, as I write this, was actually tomorrow, because New Zealand is on the other side of the international dateline so it occurred officially at AM on the 23rd local time, but that was the most recent of several aftershocks. In all of those areas where quakes often struck, we could assume there was a dense web of faults lying below ground, of which we're aware of just a tiny fraction.
There are probably ones like that all over New Zealand. Particularly, scientists are intensely interested in the Alpine Fault, which they probed with a deep drilling project north of Franz Josef Glacier in Dr Ristau said earthquakes of magnitude 7. It last ruptured in , or years ago, and had a 28 per cent probability of rupturing in the next 50 years - a rate high by global standards. According to GNS Science, this rupture would produce one of the biggest earthquakes since European settlement of New Zealand, and would have a "major impact" on the lives of many people.
Meanwhile, scientists have just revealed new insights into the Kerepehi Fault, which runs for about 80km between Matamata and north into the Firth of Thames. Research just shared by GNS Science today showed that the fault is more complex than previously thought. Previously, the fault was thought to consist of up to five loosely connected single strands or segments, but the new findings show it actually consists of a belt of many faults, in a wider zone suggesting a more complicated arrangement of segments.
Scientists had earlier understood the average interval between ruptures of the Kerepehi Fault was between and years, based on the better studied segments.
Although there is one period several thousand years ago when three quakes appear to have clustered relatively closely in time. However, the new research combined the rupture history of all fault segments studied so far, and found the average rupture interval to be about years. In other words, the rupture interval on a single segment of the fault was still likely to be several thousand years, but the region may experience a large earthquake every years.
Previous ruptures have involved up to 2m of vertical displacement of the ground surface per event, which suggests associated earthquakes were between magnitude 6.
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