Chinese earthquake may have been man-made, say scientists

[Are_grits_groceries]

The 511ft-high Zipingpu dam holds 315 million tonnes of water and lies just 550 yards from the fault line, and three miles from the epicentre, of the Sichuan earthquake.

Now scientists in China and the United States believe the weight of water, and the effect of it penetrating into the rock, could have affected the pressure on the fault line underneath, possibly unleashing a chain of ruptures that led to the quake.

Fan Xiao, the chief engineer of the Sichuan Geology and Mineral Bureau in Chengdu, said it was "very likely" that the construction and filling of the reservoir in 2004 had led to the disaster.
<snip>
Although the official government line is that its massive construction projects had nothing to do with the quake, some state researchers in Beijing have called for a full investigation. Lei Xinglin, of the China Earthquake Administration, said that the Zipingpu reservoir "clearly affected the local seismicity and it is worthwhile to study the role it played in triggering the earthquake further". He added that firm conclusions remain "premature" however.

There is a history of earthquakes triggered by dams, including several caused by the construction of the Hoover dam in the US, but none of such a magnitude.
http://www.telegraph.co.uk/news/worldnews/asia/china/4434400/Chinese-earthquake-may-have-been-man-made-say-scientists.html

Damn!!

[TheWraith]

1. I believe this is an "Oh, shit" moment in engineering. nt

[FLyellowdog]

2. And I thought only God could make a tree...or earthquake...or whatever.

[dixiegrrrrl]

3. And so ends our episode of

"Quiet...Geniuses at Work"

Stay tuned next week when we bring you :

"How to dog paddle in 315 million tonnes of very rapidly moving water"

[Xithras]

4. Sure, but...

What is the aggregate weight of all the buildings in San Francisco? If the San Andreas slipped under SF, could you blame the failure on the additional downward force exerted on those buildings? Yes.

Earthquake faults work by continually building up force until there is a tensile failure (earthquake). By adding weight to a loaded fault zone, you add additional force and hasten the failure of the underlying rock. ANY construction near a fault line WILL have an impact on the underlying faults. In most cases that impact is negligible, but in a few (big dams, major cities) the additional strain may move the failure date up by days, months, or centuries.

The important thing to remember is that the fault would have failed anyway. Human impacts may change the timelines a little, but those points would have failed eventually. If human construction pushes up the failure date of an earthquake that kills 100 people, by one year, is the construction project really responsible for the quake?

[bushmeister0]

5. So building a nuclear power plant on a faultline is OK, right?

It's always mystified me why anyone with a half a brain would build an N-palnt on the Diablo Canyon fault in CA., not that anything has ever happened there.

NYT Aug. 5 1985:

"A strong earthquake shook a large area of California early today, jostling people out of their beds but causing no serious damage or injuries.

The earthquake shook the Diablo Canyon nuclear power plant near San Luis Obispo, 60 miles southwest of the epicenter in Coalinga, but had no effect on plant operations, John Angius, a spokesman for Pacific Gas & Electric, said."

http://query.nytimes.com/gst/fullpage.html?res=9D00E5D61038F936A3575BC0A963948260

[Ian David]

6. What happens to the tectonic plates when glaciers melt away from them? n/t

[Are_grits_groceries]

7. We might just find out.

That's a lot of weight being lifted off. something will probably give.

[ecstatic]

8. global earthquaking

:scared:

[jberryhill]

9. The pressure is going to build up regardless

One might just as well claim that stimulating a quake relieves stress that would have only built up to cause a larger quake in the future.

Not a geologist here, but this seems like a reach.

[applegrove]

10. Apparently there were earthquakes after the Hoover Dam was built too.