The Shakey City – Christchurch, New Zealand

I thought to start off my blog, I would write a bit about my home town. I live in Christchurch, New Zealand (have done all my life). As a “Cantabrian”, I am now very familiar with a geological phenomenon called Earthquakes. So this blog is going to look at the science behind what causes earthquakes, as well as some post-earth quake tourist information for Christchurch.

So, here we go!

The outer surface of the earth is called the crust, and it is not a continuous piece. It is made up of 7-8 major plates, as well as many minor ones. The plates sit on a molten layer, called the mantle, and the edges of these plates are called plate boundaries.

New Zealand as a whole sits on a pretty major plate boundary, between the Pacific and the Australian plates. These two plates are slowly moving relative to each other. At the end of the South Island, the Australian plate is moving underneath the Pacific plate, while at the tip of the North Island the Pacific plate is moving under the Australian plate. This creates a pretty large area (most of the length of the south island in fact), where the plates are grinding against each other. This creates the Alpine fault line, which is a large fracture caused by plate movement.

quake-map_large

However there are tons of smaller fault lines all over New Zealand, including one that was discovered on September 4th 2011, when the pressure from the plate movement became so great that the fault ruptured, causing an earthquake measuring 7.1 on the Richter scale.

(By the way, GNS Science has an awesome interactive map showing the active faults in New Zealand. You can check it out here)

But what does a 7.1 magnitude earthquake mean? Well as somewhere who has been through it, it means the earth quakes! However we can break it down into more empirical terms. There are two things that influence how strong an earthquake seems to us; the magnitude of the seismic movements, and the depth at which they occurred. Magnitude is normally measured by the Richter scale, which is a log scale from 1-10 specifically for seismic movement. A log scale means that each number on the scale refers to an earthquake 69383_1480543056427_1119227_n10 TIMES GREATER than the number before it. So a magnitude 7 earthquake is 10 times stronger than a magnitude 6.

Up on the earth’s surface, you probably won’t feel any earth quakes under a magnitude of 3. Small earthquakes happen all the time, and are only recorded by very precise instruments called seismographs. The magnitude 7.1 and 6.3 earthquakes in Christchurch caused A LOT of damage, and while no one died in the September earthquake, 185 people died in the 6.3 earthquake 39600_1480541616391_3205413_non February 22nd.

Hang on, if the February earthquake was smaller, then why was it worse? Well this comes back to depth. The February earthquake was closer to the surface, and closer to the city. The direction of the movement can also play a part in the amount of damage caused.

(There is another interactive map that illustrates earthquake occurrences across Christchurch. This includes buttons to replay the earthquake activity seen on September 4th and February 22nd, so you can compare them to a normal day. View it here).

 

“That all sounds awful. Why would you ever want to visit Christchurch?”

 

71708_1480542336409_3861443_nWell the earthquakes were 5 years ago, and even though there is still a lot of rebuilding going on, there have been some really cool things “pop up” in Christchurch. In fact, we created a whole culture around it.

As the central city has opened back up, the buildings left standing have been painted with a variety of large murals. Everything from traditional graffiti style to a detailed ballerina! These won’t be around forever, as they will slowly be obscured by new buildings, however it call-me-snakeadds an incredible dash of colour to the city. Check out Scape Public Art for more information on these works.

A Container Mall has also opened in the city, called Re:Start. The entire mall is built out of shipping containers, painted all colours of the rainbow. It’s a really cool place to wander around, with funky clothing stores, coffee shops, and food stalls. The Re:Start mall also has Quake City, which is a special exhibition by the Christchurch Museum, focused on the Christchurch Earthquakes. So if I have peaked your interest on geology, you can check out some cool interactive activities there. Including measuring your own seismic activity by jumping restart-mallon a specially designed sensor! You can find more information about retailers at the Re:Start Malls website.

If you’re into the outdoors, and some epic views, the Port Hills in Christchurch offers scenic views over both Christchurch and Lyttleton Harbour. The Lyttleton and Akaroa harbours are formed by two extinct volcanoes (I know, New Zealand is full of awesome geological phenomenons!). There is a gondola that goes up the side of the hills, and they have a nice restaurant at the top. The gondola will also transport mountain bikes, so you can take your bike to the top and enjoy a breath taking ride down. Price and transport information is available on the Welcome Aboard Christchurch website, as well as information on other Christchurch attractions.

There are plenty of other things to do in Christchurch, and the surrounding district of Canterbury. I have been caving and rock climbing in the north of the district, had fudge at the beautiful French town of Akaroa, and relaxed in hot pools at Hanmer. You can find out information on all of these things and more at the Christchurch Information Center. Or Leave a comment about a spot that interests you! I would be glad to write a post about it – includes a free science lesson!

12 thoughts on “The Shakey City – Christchurch, New Zealand”

  1. Christchurch sure is an amazing city! Excellent post Jamie, as a Cantabrian I know a lot more about earthquakes than I used to but I’ve still learned some things after reading this. I’ve been meaning to go to Quake City for a while but never get around to it. You’ve got me excited to finally go!

    1. Thanks Katie! To be honest I haven’t been in to Quake City either. I kind of figured that I had lived it, so didn’t need to go, but I should go check it out. Summers coming up, so I will have to make a day trip into town.

  2. I’ve actually never experienced an earthquake I think I’d freak out for sure! Christchurch sounds like an amazing city despite the earthquakes, its my dream to visit New Zealand 🙂

    1. Hi Natasha, thanks for reading. I will be writing a lot more about New Zealand, particularly the South Island where I live, so you should definitely check back for more cool things to do in New Zealand.

  3. I’m heading to NZ next month but sadly time won’t permit making it to Christchurch. I remember the quake well and it’s fabulous to see the rebuilding is well under way. I love that you have some temporary art to enjoy in the meantime!

  4. How fantastic the rebuild of the city is! I love the large murals! I’ve been in a few nasty earthquakes while in San Francisco and big ones are quite scary but it always amazes me how we as humans stay strong and rebuild! My aunt once told me that you get used to it and don’t even notice the small tremors. I suppose that’s true, after while you can get used to any surroundings, like living next to train tracks! great read and love that you covered how the earthquakes occur and why!

  5. I’ve been to New Zealand a few times and is one of my favourite countries. Christchurch is a beautiful place and it’s such a shame that it got hit by earthquake.

  6. Thanks for such a detailed post. The earthquake pictures kinda freaked me out, but there’s no way I’m not visiting New Zealand. I have a couple of friends who keep posting pictures of the great outdoors and I get jealous everytime. Its just so beautiful & green (I live in a desert by the way).
    I’m even interested to measure my own seismic activity too haha.

  7. I loved Christchurch I was there at the end of 2012 and so I saw the container mall, what a great idea, but it was such a pity that so many tourists were avoiding the city. I also went back just after the gondola re-opened and the view from the top was amazing. I also did a trip to the zoo which was good too.

  8. I have never been to NZ. I would love to visit, though. However, I have to admit that I did not hear or know about the earthquake few years back. Hope the city gets finished re-building soon.

  9. Rebuilding after an earthquake is such a huge task. It doesn’t surprise me to read that 5 years later restoration is still taking place. I wouldn’t hesitate to visit Christchurch. There is so much to see within the rebuilding efforts.

  10. Luckily, I have never experienced an earthquake. I think it is one of the most scary things to happen. Forces of nature are so strong. I do like how the people of Christchurch used the open areas to let their inspiration run free and make some new and fresh out of it.

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