Monday, November 14, 2016

Regarding the recent quakes...

In case you haven't heard, there was a massive 7.5 earthquake north of Christchurch (near Hamner Springs) that struck last night just after midnight.

Unlike the previous ones we've had, this one went on for a very long time - for some 2-3 minutes by our rough estimation... much much longer than any previous quakes we've seen (and we've seen literally thousands in several years at this point). It was also relatively gentle (comparatively speaking): instead of any sharp jerking, shuddering, or horizontal shunting (i.e. the most destructive type of quake motion), we were instead treated to a "lost at sea in a heavy swell". The ground seemed convulse beneath our feet in wobbly waves of undulating motion. Combined with the gentle swaying of all the walls, light fittings, and other free-standing objects, the flickering lights (which threatened to blink out at any moment), and doors banging open and closed, it was quite a sickening feeling. I can only image how bad sufferers of motion sickness find travelling to be...

From our previous experience with the Cook Strait quakes earlier this year (or was it last year?), I could safely conclude that the quake was at least not located too close to Christchurch (i.e. it would be closer up to the Marlbrough/Wellington area), but that it was a big quake (due to the length of the shaking). Which of course led to the suspicion during the event that perhaps this was the massive Alpine Fault finally going off, as they've been predicting for years. It wasn't.

Fortunately, in Christchurch, we've so far come off relatively unscathed. Shaken, shocked, and riddled-with-anxiety: yes. Slightly sleep deprived: yes. But luckily none of the things that usually fall down have done so (probably as there wasn't the big horizontal shunting movements that tend to sweep everything to the ground). People living "near the coast" (*) were evacuated overnight though due to the disturbing finding that there was some tsunami activitiy happening out there (i.e. a gauge at the Kaikoura station indicated some 2m high swell was starting to race through).  (*) One thing that they could've communicated more clearly though is what they mean by "near the coast" in their initial reports. (It took some checking, but apparently 3km should be a sufficient distance, meaning that most of us should be fine if we're further west than Hagley Park...)

People further north have not been so lucky.

In Wellington (i.e. the capital city, and where we'd spent a day last month on a little getaway to attend the Wearable Arts show again this year), the CBD was closed, with quite a lot of buildings suffering damage (e.g. broken glass, falling concrete, and a few with structural damage + damaged infrastructure).

But the hardest hit region has been Kaikoura. (About 12 years ago, we took the train up there with Granny for a daytrip, and probably the last trip we went on together....  For the rest of the world, this is the "Whale Watch" township). Apparently the only roads in and out are all blocked by landslides, and the power, water, and communication lines have all been severed as well. Recent news reports also say that there is widespread devastation there. Basically, pretty bleak stuff....  (For the uninitiated, the roads in and out of Kaikoura are really scenic, as they basically wind along the coast - a tiny ledge between the hills and the roaring surf below, with seals and sea lions camped out on the rocks below as you pass. The train lines run parallel to the road. These roads are the only way in or out of Kaikoura. They also pass through a series of tunnels. From the reports I've heard, landslips have blocked some of the tunnels, while other parts of the road have given way and fallen into the sea. Other photos show that the roads around the area show large cracks in the road).

Meanwhile, the aftershocks continue to roll through. There have been heaps already - apparently 100's (many in quick succession, spread all over the country, but primarily around the affected region) have been striking the affected region. Down here in Christchurch, we've also felt a few few of these - again, long, slow-churning jelly quakes, corresponding to aftershocks of 5+ .  Just earlier this afternoon, there was a biggish aftershock of around 6.3/6.6 that caused about a minute or so of churning. The nasty thing with these churning quakes is that because they last so long, it becomes hard to tell whether they're still going, or whether it's your innards that are still sloshing around in a dazed soup of confusion.

Why world does this week have to be such a mess?! Surely you didn't have to set an earthquake upon us to make the Americans think twice about moving down here to get away from their new President-elect, right? :/

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