How earthquakes work, and how science makes us safer

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17 Responses to “How earthquakes work, and how science makes us safer”

  1. penguinchris says:

    Great interview. As a geologist I already knew all this stuff, but I enjoyed reading it anyway :)

    Regarding engineering earthquake-proof structures – it will always be true to some extent that you don’t know if a new design will hold up the way you expect until you get a large earthquake. However, the science and engineering (and testing) that goes into such designs is incredible, and they do actually know quite well how these things should react.

    In fact I’d go so far as to say it’s a solved problem – for new construction in earthquake-prone areas, there’s no reason to expect structural failure in an earthquake, except in circumstances that are way out of what’s normally expected (and while rare and exceptional, a 9.0 off the coast of Japan is not totally unexpected).

    The problem is of course paying for it, and retrofitting existing structures. In Japan they’ve done this quite well, but even in California this isn’t the case – there are still a lot of older buildings that are not “up to code”, although there is plenty of money spent on retrofitting in California.

    In the rest of the world’s earthquake-prone areas, there is little to no money spent on retrofitting, and new construction is, realistically, unregulated (bribes and corruption ensure this continues despite what the law may say) – and done on the very, very cheap.

    Wood-frame construction as is common in the US is actually very earthquake-safe; I’ve seen videos of full-scale wood houses on shake tables being hit with massive shaking with no structural damage. Most of Asia and the Pacific does not extensively use wood-frame construction, and you see a lot of concrete structures especially. This requires a lot more engineering to survive a large earthquake, which simply doesn’t get done in many places.

    Just as an example, I did research on tectonics in Thailand in grad school – it’s actually not at all an earthquake-prone place, despite its formation being related to the India-Asia convergence, so this isn’t surprising – but the construction there is awful. I’ve seen new structures going up that look like they’re made out of concrete playing cards and toothpicks. The old stuff (and most of it is old, even in Bangkok where everything is constantly under construction) is even worse.

    Further, tsunami warning systems and education about what to do is entirely lacking in the pacific, except in Japan, including the places that were hit by the tsunami in 2004.

    I mean heck, in many of the videos coming out of Japan, you see lots of people who weren’t doing the right thing while the earthquake was happening. Really basic stuff. And this is easily the places with the most awareness and education regarding earthquakes in the entire world. So it certainly isn’t an easy problem.

    • Michael says:

      The reason concrete is used extensively in many parts of the world is that hurricanes are a more frequent problem than massive earthquakes. Wood frame construction fares very poorly in a hurricane.

    • Anonymous says:

      “In the rest of the world’s earthquake-prone areas, there is little to no money spent on retrofitting, and new construction is, realistically, unregulated (bribes and corruption ensure this continues despite what the law may say) – and done on the very, very cheap.”

      I think its a bit over the top to claim that USA and Japan are the only two earthquake prone countries that don’t suffer from unregulated construction practices, bribery and corruption? New Zealand would be one country that springs to mind as having a similar standard of building codes and a regulated construction industry

  2. planettom says:

    More than “Are the New Zealand and Japan quakes related”, my question would be, is the erupting volcano Shinmoedake (other end of Japan, the one from YOU ONLY LIVE TWICE) directly related to this quake, or not really?

    Similar to the way that, around the time of the Haiti quake, that Caribbean volcano Monserrat was more active.

    • Ipo says:

      Yeah, I’ve been thinking that. And Kilauea in Hawai’i, sort of in the middle between New Zealand, Japan and California is unusually active since last weekend. Had some minor quakes too.

  3. Anonymous says:

    When I first heard about the earthquake this morning I remember my Mother telling me, in the 1960′s, that she thought we should expect to see more earthquakes here on the west coast after quakes in Japan. I’ll be paying attention now.

  4. DrPretto says:

    Thanks Maggie. Excellent interview, very informative.

  5. Olifiers says:

    This might sound like fringe science as I’m unaware of any geological study on the subject, but it’s a very basic thermodynamic principle: if something is heated up, it dilates.

    Seems to me quite an overlook to not consider what effects climate change can have on the planet’s crust. If its temperature goes up, its surface will experience expansion. Such expansion would be translated into more friction between the tectonic plates, volcanic activity and so on — precisely what we have been experienced in the past decade.

  6. Shawn Guse says:

    We can always learn from earthquakes and natural disasters.

  7. Anonymous says:

    Did science help Haiti or did poverty get in the way?

    • AnthonyC says:

      Both, I would say.
      Obviously, poverty prevented Haiti from making the kind of earthquake preparations that Japan (or Chile, or even the Dominican Republic) made, but science still allowed the international community to get aid to Haiti almost immediately, making the impact much less than it would have otherwise been.

  8. Anonymous says:

    “making it the most powerful earthquake to ever hit Japan”

    Can I be a total pedant and point out that it is highly unlikely to be the most powerful earthquake ever. It is the most powerful recorded earthquake to to hit Japan.

  9. DrPretto says:

    Thanks Maggie. Excellent interview, very informative.

  10. Anonymous says:

    This was really interesting, especially the bit about the unpredictability of wave size at the opposite end of the ocean from the earthquake. Here on the southern Oregon coast, our sirens keep going off, we keep hauling up the bluff to higher ground, and then watching as a not-so-scary 2 foot swell rolls in.

    I imagine that some measuring device somewhere triggers these warnings to clear the coastline, yet the devices are unable to say whether the freakout is really warranted or not.

    • travtastic says:

      I’m pretty sure it’s always warranted. It’s a mild inconvenience to have to go to high ground when it gets a false positive, but the alternative is you possibly drowning or being bashed to death by a wave.

  11. Anonymous says:

    Science may make us safer but economics will always trump science. If a safeguard is expensive it might as well not exist for most people. Office towers may stay up but the worker’s homes collapse.

    • GlenBlank says:

      If a safeguard is expensive it might as well not exist for most people. Office towers may stay up but the worker’s homes collapse.

      Yes, but quake-proofing lightweight low-rise buildings is much simpler and cheaper than quake-proofing large high-rise towers, so unless you’re housing your workers in shoddily-built high-rise tenements (or cheap-ass prefab concrete Khrushchyovkas), worker housing can be protected at very little additional cost.

      LA is often derided for its stick-built, stucco-walled, asphalt-shingled single-family homes and one-to-two-story courtyard apartments, but such structures are inherently (almost) quake-safe.

      Make sure the wall panels have some cross-bracing, bolt the wall frames to the foundation, strap down the water heater, and install an automatic seismic shutoff on the gas line, and you’re good to go.

      It’s no accident that so much of LA’s housing stock is built this way.

      Those measures add only a negligible amount to the cost of building housing, and are even affordable as a retrofit.

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