

5.3-magnitude earthquake hits Japan's Fukushima - velodrome
http://news.yahoo.com/-5-3-magnitude-earthquake-hits-japan-s-fukushima-184440374.html

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jofer
A lot of folks are probably wondering "why the heck would they put a nuclear
power plant there?".

If you look at the distribution of Japan's nuclear power plants, they actually
tried to put them in the safest areas: [http://www.oecd-
nea.org/press/2011/NEWS-02.html](http://www.oecd-
nea.org/press/2011/NEWS-02.html)

Where there are nuclear power plants along Japan's eastern coast (close to the
subduction zones), they're mostly in the north.

Japan has two subduction zones. The Japan Trench in the north, where the
Pacific plate subducts, and the Nankai Trough in the south where the
Philippine Sea Plate subducts.

These two subduction zones are very different. They're on opposite ends of the
spectrum in terms of earthquake behavior.

Before the Tohoku earthquake in 2011, we had never observed a magnitude 9
earthquake on a subduction zone like the Japan Trench in the north of Japan.
(The Japan Trench usually has frequent magnitude 7's. Damaging but not
devestating.) All of the previous magnitude 9's were on subduction zones
similar to the Nankai Trough in southern Japan.

Furthermore, southern Japan has a 1300 year written historical record of large
earthquakes and tsunamis occuring every ~200 years (they're not regular, but
that's another story). The last two were in 1944 and 1946. In contrast,
northern Japan has just as long of a record, but no records of very large
earthquakes and tsunamis. (There's some sedimentological evidence of a very
large tsunami in northern Japan ~2000 years ago, but prior to this, we assumed
that it must have originated somewhere else.)

Therefore, southern Japan has the highest hazard for large tsunamis, and
northern Japan has a much lower risk. Northern Japan's risk is now higher than
we thought it was, but southern Japan is still more likely to have the next
big tsunami.

Notice that there are very few nuclear power plans on the east coast of
southern Japan. Instead they're on the west coast, away from the main tsunami
hazard. That's why.

At any rate, the Tohoku earthquake really turned what we thought we know about
very, very large earthquakes on its head.

~~~
afterburner
Folks might be wondering that, but they might be wondering with a different
emphasis:

"why the heck would they put a _nuclear power plant_ there?"

Not sure what their power options were at the time it was built though.

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timtadh
Japan has very few natural energy resources which is the main reason they
embraced nuclear power in a big way. Otherwise, they would have to import many
more tons of hydrocarbons.

~~~
timr
_" Japan has very few natural energy resources"_

Except that the place is _covered_ in geothermal hotspots.

I don't know if any are sufficiently large to reduce the need for nuclear, but
Japan is a country where the greatest natural energy resource appears (to an
outsider) to be dedicated to providing really nice baths.

~~~
jofer
Actually, it's not as covered as you might think.

Japan's relatively cold (in geothermal terms) due to its tectonic position.
(It's counter-intuitive, but forearcs have relatively low geothermal gradients
for such tectonically active areas.)

The main areas of geothermal potential are localized around the volcanic arc.
Most of this land is inside of national parks.

Compare this to areas like Iceland or most of the African rift, where you have
a very high regional geothermal gradient. Anywhere you can find deep
permeability, you'll have potential for geothermal power generation.

Japan certainly has a lot of geothermal potential, and hasn't utilized most of
it yet, but it's not as simple as it seems at first glance.

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NovemberWest
Wow, really? These questions are like criticism of people who live in flood
zones. Yeah, we should all avoid water like the plague. We don't need it to
drink or grow crops or foster basic transportation. Have you ever looked at a
map of "disasters"? You cannot escape them. It is a case of pick your poison.
Which type of risk scares you less?

Japan is a densely populated, urbanized, modern country. It requires
substantial electricity. That electricity has to come from somewhere.

~~~
null_ptr
Nuclear disasters like the one at Fukushima affect the entire globe, not only
Japan. If the country is geographically unfit for nuclear plants, then no
nuclear plants should be built there, period. Otherwise the entire region's
safety is compromised, not just Japan's.

~~~
aasarava
Financial disasters like the one in the US in 2008 affect the entire globe,
not only the US. If the country is morally unfit for advanced banking, then no
advanced banking should occur there, period. ... ?

~~~
tazey
Non-US banks, countries, and individuals choose to do banking with the US and
form a "marketplace."

Non-Japanese have no say whatsoever in Japan's nuclear industry. They only
suffer the "externalities."

~~~
VladRussian2
Japanese have no say in CO2 emissions by any other country, including ones
relying on coal plants. Yet they suffer from the externalities of it.

Tragedy of commons. WWI -> League of Nations, WWII -> UN ... How about
establishing a world government without WWIII this time. Though what the frak
i'm talking about if we can't even stop a government from butchering tens of
thousands of their own people (like Sudan, Siria)

~~~
dllthomas
WTO?

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nostromo
[http://en.wikipedia.org/wiki/Diablo_Canyon_Power_Plant](http://en.wikipedia.org/wiki/Diablo_Canyon_Power_Plant)

> Diablo Canyon Power Plant is an electricity-generating nuclear power plant
> at Avila Beach in San Luis Obispo County, California.

> It was built directly over a geological fault line, and is located near a
> second fault.

~~~
skelsey
It's also built 80 feet above sea level.

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jmadsen
Match this:
[https://en.wikipedia.org/wiki/File:NRC_regions_and_plant_loc...](https://en.wikipedia.org/wiki/File:NRC_regions_and_plant_locations_2008.jpg)

With this: [http://strangesounds.org/wp-content/uploads/2013/07/US-
FAULT...](http://strangesounds.org/wp-content/uploads/2013/07/US-FAULT-
LINES.jpg)

(for those who miss the significance:
[https://en.wikipedia.org/wiki/New_Madrid_Seismic_Zone](https://en.wikipedia.org/wiki/New_Madrid_Seismic_Zone)

"The zone had four of the largest North American earthquakes in recorded
history, with moment magnitudes estimated to be as large as 8.0," )

~~~
jofer
...Grumble, grumble... "Fault lines"...

This has absolutely noting to do with your very astute point, but I really
wish the term "fault line" hadn't somehow wound up in popular culture.

Faults are never lines. They're irregular surfaces that sometimes form lines
at their intersection with the earth's surface (they also sometimes form
circles or don't intersect the surface at all).

...Okay, I'll stop ranting about things that only geologists care about...

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speeq
"The region lies on the "Ring of Fire" — an arc of earthquake and volcanic
zones that stretches around the Pacific Rim. About 90 percent of the world's
quakes occur in the region." \--

Who had the brilliant idea to build a nuclear power plant there... :\

~~~
jofer
To be fair, it's not like Japan has much of a choice. Nuclear really is their
best option. Japan has only a couple of coal mines, and they've deliberately
tried to avoid being entirely dependent on China for coal imports. This limits
the use of coal power plants (not to mention environmental consequences). They
have limited area, which limits hydropower options (though the steep
topography partly makes up for that). Wind and solar are limited in their
utility for "baseline" power.

The US has nuclear power plants on the "ring of fire" as well, for whatever
it's worth (e.g. Diablo Canyon in CA, and I think there's one in Washington,
as well).

~~~
grey-area
Wave power would be a good alternative to explore.

~~~
jofer
Good point!

It has many of the same problems as wind and solar, though. They're great as a
significant part of the energy input, but you still need something else for
times when there's no wind/waves/sun.

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bhz
It is now also home to a bunch of (already) leaky, radioactive, coolant water
containers. Earthquakes are not going to improve their situation.

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bsullivan01
tough neighborhood, is all I can say
[http://www.theglobeandmail.com/technology/science/japan-
sits...](http://www.theglobeandmail.com/technology/science/japan-sits-atop-
deadliest-section-of-ring-of-fire/article572438/)

