New Zealand Earthquakes: Comparing 2011 & 2016
Strolling around the internet, looking for additional info for my planned post this week, I visited the New Zealand Herald website and was expecting to see sheep, John Key, or some article about Donald Trump becoming president-elect of the United States. As shocking as the latter news was when it arrived last Wednesday morning in Germany, the news of another heavy earthquake on New Zealand’s South Island this week was terrifying in another sense. Earth’s tectonic plates don’t stop moving just because the world is stunned at the outcome of the US election.
Just like many members of our class have mentioned in their posts, I don’t really know much about New Zealand. Sure, Lord of the Rings was filmed there, the landscape is magnificent, there are lots of sheep, and the flag debate was kind of an international joke. But there’s also the big Christchurch earthquake in 2011. The images of the damaged inner city of Christchurch went around the world and have made a lasting impact. So when I read that Kaikoura, north of Christchurch, was hit by a strong earthquake, my thoughts were “Oh no, not again.” Although, to be honest, I have no idea if 5 years between two large earthquakes is a long or a short time, the memory of the quake of 2011 still seems fresh.
However, the both quakes are only at first glance very alike. They occurred in roughly the same region of the South Island, were both strong (6.3 and 7.5–7.8 on the Richter scale respectively) and both caused tsunamis. For one, the 2011 earthquake occurred only 5 km beneath the earth’s surface and that is why it was so devastating: the shallower the quake, the more destruction it causes. And 2011 saw a lot of destruction. Although the earth shook only for about ten seconds, office buildings collapsed in downtown Christchurch, homes were destroyed, the cathedral was badly damaged and, the most tragic part, 185 lives were lost and many more injured. The earthquake and its aftershocks (of which 3 had a magnitude of over 6.0 on the Richter scale) generated a cost of roughly $25 billion and a significant decrease of the population. Luckily, although the recent earthquake in Kaikoura was even stronger and lasted longer than that in Christchurch 2011, it occurred between 15 and 23 km beneath the surface and thus seems to have been less destructive in total. I don’t mean to trivialise; the images of the region show a lot of upset soil, huge cracks and craters in roads and, on a lighter note, cows stranded on an “island” of intact soil. The damage is considerable and is estimated to cost billions to repair. Two people have lost their lives so far, but authorities happily do not expect this number to rise. There have been at least four aftershocks with a magnitude over 6.0 and they keep coming, as the Christchurch quake map shows.
New Zealand’s location on the ring of fire means that it has a high chance of experiencing significant earthquakes. Japan, for example, is also located on this infamous ring and has a working early warning system for earthquakes and tsunamis which can provide vital seconds for the population to take measures for protection. I was unable to find any information on a similar system for New Zealand. Maybe my google skills have failed me. Maybe I just didn’t read closely enough. But if New Zealand really lacks a warning system, there is one big question that keeps rotating in my mind: Why?
