Merged 8.8 quake in Sendai, Japan

[The Central Scrutinizer]

Nuclear thread is thataway...

This one works fine.

 

[kmortis]

It has been determined that the discussion of the Quake in Japan is inexorably intertwined with the discussion of the nucular plants and their status. Therefore the discussion of the plants is on-topic for this thread.

Replying to this modbox in thread will be off topic  Posted By: kmortis

 

[Skeptic Ginger]

That's very true. The vast majority of the fatalities this time seem to be due to the tsunami, not to the earthquake.

How widespread was the old Japanese practice of building very flimsy houses to minimise casualties in earthquakes, as seen in the first scene of Madam Butterfly? I've heard much of the damage in 1925 was related to the adoption of western construction methods based on brick, without realising these structures performed very poorly during earthquakes.

Rolfe.

That sounds a little noble-savage-mythy. Not saying the term 'savage' has anything to do with it, but the myth is akin to saying the American Indians lived in harmony with the environment. In reality they did not. There just were less people in a larger environment. Driving buffalo off cliffs en mass was not much different from shooting them in a pen.

On the other hand, anyone who has encountered a seatless Western toilet in Mexico where people still squat on the rim knows there is indeed some folly when Western ideas are valued over local customs like squat toilets. Sometimes in a desire to adopt a Western idea, something gets missed in translation.

What I find hard to buy here is the idea a change in construction had to with 'adopting' western methods. I suggest an alternative hypothesis. Wood construction if done right, is flexible in an earthquake. Some of Japan's ancient buildings are wooden master craftsman feats of wonder. But Japan's population is greater than their supply of wood can provide housing for. Building with other materials was inevitable.


But I'm interested if you have any more information on your thoughts.

 

[jayh]

That sounds a little noble-savage-mythy. Not saying the term 'savage' has anything to do with it, but the myth is akin

I was thinking that as well. Being in a flimsy wooden frame house during an earthquake is quite likely to be fatal too. A tent is about the only low tech structure that is unlikely to kill many inhabitants.

 

[Rolfe]

There was an interesting item on Channel 4 News about the relief effort. It focussed on Taro, a district of Myako city, which was inundated despite having absolutely massive tsunami walls and harbour gates.

Some people are questioning whether the worst-hit areas should even be rebuilt at all. In northern Japan, some of the highest sea walls in the country were previously found in the fishing town of Taro. They were built after a tsunami nearly seventy years ago, yet the town has suffered widespread damage and its citizens left reliant on outside aid.

The port's web site still boasts that the vast sea walls here will stand any tsunami. They took 25 years to build, their massive sluice gates capable of withstanding anything. And look at these sluice gates today. Bust open, high-grade steel contorted like cheap plastic. Look at the tsunami walls they were so proud of. No wonder the debate here is beginning - no longer about how to rebuild and re-defend, but whether to.

By the look of these gates, it wouldn't have made any difference in Rikuzentakata whether their gates had been closed or not.

Another BBC report from Rikuzentakata showed the undamaged high school, built high as a defence against tsunamis. The children were in school, and have pretty much all survived, along with the teachers. The parents were mostly working down in the town. There are a lot of orphans among these kids - they think the 500 bodies found is just the start.

Will they really decide to abandon the flat ground at the head of all these picturesque coves and not build on it again? What about all the similar towns in the same vulnerable location that just didn't get hit this time?

Rolfe.

 

[Dan O.]

The flat lands are much better suited for farming. Why don't they build the houses on the hillsides overlooking the valley.

 

[Rolfe]

Maybe that's what they're considering. Easy to do now in Minamisanriku and Kennesuma and Myako and Rikuzentakata now, if you can iron out the problems of land ownership. Not so easy in the towns that didn't get hit this time though.

Rolfe.

 

[Hindmost]

Looks like they may do something similar here as they did in Chernobyl:

I have been thinking about this for a bit...I really don't think they will go with the concrete entombment until everything is completely beyond any hope. It would go against the culture somewhat. (maybe)

glenn

 

[The Central Scrutinizer]

I have been thinking about this for a bit...I really don't think they will go with the concrete entombment until everything is completely beyond any hope. It would go against the culture somewhat. (maybe)

glenn

So we're not beyond hope yet?

 

[r-j]

They said they have to remove all the water before they can bury it. And remove the fuel rods.

 

[The Central Scrutinizer]

They said they have to remove all the water before they can bury it. And remove the fuel rods.

If you remove the fuel rods, what's the point of burying it?

Glenn?

 

[boooeee]

Emperor Bobble-Head.

Japan's so awesome that their Emperor can activate the big-head cheat code in real life.

 

[Puppycow]

I saw yet another report from Rikuzentakata on the lunchtime news. Only a few structures are left standing (fire station included), but these seem to be gutted by the water rushing on one side and out the other. They're still looking for the bodies of the firemen who rushed to try to shut the harbour gates as the tsunami approached, and they weren't closing automatically. That report said that 500 bodies have been found, but that 10,000 of the town's 26,000 population are still unaccounted-for.

The lunch-time report said this could be the most devastated town of the lot. However, it has stiff competition in that race. And it's not even one of the larger ones - several of the places seen crumbling under that wall of water had populations topping 70,000.

I really can't make out whether the real death toll is indeed "only" going to come out around 15,000, or whether the sheer scale of the catastrophe means the half has not yet been told us.

Rolfe.

The problem with Rikuzentakata seems to be topographical. The bay is shaped like a funnel so that the force of the tsunami was concentrated on the town itself, reaching 15 meters (50 feet) in height.

I suspect that >99% of those still missing are dead too (although perhaps there may be some overlap if all bodies have not been identified).
Dead and missing up to 21,911

The number of deaths reported in 12 prefectures came to 8,649, while those reported missing by relatives climbed to 13,262 in six prefectures. Police have identified about 4,080 bodies, including 2,990 that have been turned over to relatives, the agency said.

So roughly 4600 bodies have yet to be identified. If we assume that they have all been reported missing, that's still over 17,000.

Perhaps a quarter to a half of the missing bodies will have been swept out to sea, and hence will never be found.

 

[gumboot]

That's very true. The vast majority of the fatalities this time seem to be due to the tsunami, not to the earthquake.

The actual earthquake wasn't particularly violent, and it was a long way off shore. Peak ground acceleration nearest the epicenter was only 0.3g.

 

[Puppycow]

Interesting side point. I saw a newspaper account of the 1925 Japan earthquake which estimated the death toll at 260,000 for just Tokyo and Yokohama alone, despite much smaller populations than now. A tribute, I think, to the benefits of modern building methods and disaster management.

To clarify, the populations of Tokyo and Yokohama at the time were smaller than the populations of Tokyo and Yokohama today, but larger than the current populations of the coastal areas of Northern Japan affected by this earthquake. The epicenter of the Great Kanto Earthquake^WP was also in the worst conceivable location, much closer to the major population centers and in a spot that caused tsunami waves up to 10 meters high.

The quake had a magnitude of 7.9 on the Richter scale,[1] with its focus deep beneath Izu Ōshima Island in Sagami Bay.

Because the earthquake struck at lunchtime when many people were using fire to cook food, the damage and the number of fatalities were augmented due to fires which broke out in numerous locations. The fires spread rapidly due to high winds from a nearby typhoon off the coast of Noto Peninsula in Northern Japan and some developed into firestorms which swept across cities. As a result many people died when their feet got stuck in melting tarmac; however, the single greatest loss of life occurred when approximately 38,000 people packed into an open space at the Rikugun Honjo Hifukusho (Former Army Clothing Depot) in downtown Tokyo were incinerated by a firestorm-induced fire whirl. As the earthquake had caused water mains to break, putting out the fires took nearly two full days until late in the morning of September 3. The fires were the biggest causes of death.

Also, the wiki article estimates the death toll at 100,000 to 142,000 deaths, not 260,000. Not sure which one is more correct.

That's very true. The vast majority of the fatalities this time seem to be due to the tsunami, not to the earthquake.

How widespread was the old Japanese practice of building very flimsy houses to minimise casualties in earthquakes, as seen in the first scene of Madam Butterfly? I've heard much of the damage in 1925 was related to the adoption of western construction methods based on brick, without realising these structures performed very poorly during earthquakes.

Rolfe.

Again, the wiki article points to fires as the leading cause of death for that earthquake. I think that you are correct that brick houses don't do well in earthquakes. Modern construction methods are neither flimsy nor brick, but tend to be either light-but-strong wooden structures for smaller buildings or steel-reinforced concrete for larger buildings.

 

[CompusMentus]

A good article HERE (BBC World Service: Science In Action) about how study of the Japanese tsunami video's might help in the preparation for future seismic events of that nature.

"Without exaggeration, it will lead to a quantum leap in the way that we calculate and we estimate how fast the tsunami propagates on land," says Dr Costas Synolakis from the University of Southern California and the Hellenic Centre for Marine Research in Greece.

There is an accompanying audio podcast which can be downloaded HERE
Very interesting and informative on this subject.

Yet, even with better equipped building defences, some natural disasters will always cause devastation.
"I've been in the field in over 20 tsunamis since 1992. This was the worst that I've ever seen - it was unimaginable, even though I consider myself a fairly seasoned tsunamista."

Compus

 

[Puppycow]

There have been a number of small quakes today (just aftershocks hopefully). Just had one now.

 

[CompusMentus]

There have been a number of small quakes today (just aftershocks hopefully). Just had one now.

**** that must be nerve-wracking. Keep your head down mate..........


Compus

 

[Rolfe]

The problem with Rikuzentakata seems to be topographical. The bay is shaped like a funnel so that the force of the tsunami was concentrated on the town itself, reaching 15 meters (50 feet) in height.

I had a look at the area on Google Maps, and saw the problem very clearly. However, Rikuzentakata doesn't look like the only one. The entire coast is a series of similar bays each with a town at the head. Rikuzentakata might have been particularly badly placed, but it certainly isn't unique. The entire coastline could have been designed to be a tsunami death trap.

The very first footage that was shown on TV here on the morning after the disaster was of Rikuzentakata. The film was taken from some way back from the coast, but the sheer amount of water piling in, and the height of the wave, were amazing.


The footage from Miyako is possibly the most impressive, with film from right on the shoreline showing the entire harbour just rising up and pouring into the town in an endless wave, but actually it pales into significance when you look again at the wall of water overcoming Rikuzentakata.

I suspect that >99% of those still missing are dead too (although perhaps there may be some overlap if all bodies have not been identified).
Dead and missing up to 21,911

So roughly 4600 bodies have yet to be identified. If we assume that they have all been reported missing, that's still over 17,000.

Perhaps a quarter to a half of the missing bodies will have been swept out to sea, and hence will never be found.

I think the disconnect is between what people are saying from the actual towns about thousands missing from that town itself (and then when you add that up the numbers get real big real fast), and the numbers that have been "officially" reported missing. I don't know what level of reporting efficiency would be expected at a time like this. The truth is probably somewhere between the two I suppose.

I wonder if they'll have to do some sort of reconciliation with census records or electoral registers or something, to get the final tally. (I also wonder if some people might take advantage of the chaos to simply disappear.)

Whatever they're saying in Taro now, I don't see how they will avoid rebuilding on the danger sites. I was hearing about geological evidence of the frequency of these events, and it's hundreds of years. I'd put a bet on a decision that well, the big one has happened, carry on chaps.

Rolfe.

 

[catsmate]

There have been a number of small quakes today (just aftershocks hopefully). Just had one now.

According to my USGS feed in xearth the East coast of Honshu area has had fourteen quakes of > Richter 4.5 in the last twelve hours, including two of 6.6 and one of 6.1
That's more activity than Dublin has seen in several lifetimes.