Zipingpu Dam May Have Triggered the Sichuan Quake

bfwebster writes "An article in the Telegraph (UK) raises an interesting question: was the massive (7.9) Sichuan earthquake that wracked China last year and left millions homeless caused by ground stresses following the completion of the Zipingpu dam? As the article notes, 'The 511-ft-high Zipingpu dam holds 315 million tonnes of water and lies just 550 yards from the fault line, and three miles from the epicenter, 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.'" The Sichuan region is earthquake-prone, but has not seen anything as large as the 7.9-magnitude quake for perhaps millions of years. The Chinese government denies any connection between the dam and the earthquake and seems to be actively obstructing the access of scientists who want to investigate. The article concludes, "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."

Comments

It would have likely occurred anyway

[EmbeddedJanitor]

The dam might have just brought the event forward a year or two. Fault lines are natural stress relief areas anyway.

As with all things geological, there are a lot of unknown variables, hence the "could", "might" and other diluting terms.

Re:It would have likely occurred anyway

[Fluffeh]

but the proper way to look at it is the earthquake brought the geology back to a neutral point

Why on earth would you say that? Earthquakes don't bring geology to neutral points. They happen when the earth gets past critical point.

I can't think of a totally slashdot car analogy, but here is a good analogy of earthquake causes and how it works geologically that at least includes a car.

Think of a piece of bungee cord 10 meters in length. You tie one part to the tow-ball of a car, and hold the middle of the cord. This means there is five meters of slack cord past the point where you are holding. Now, the car very very slowly starts to drive away from you, and the tension in the cord slowly grows. You holding onto the cord with all your might represents the pressures on the fault line. Sooner or later however, the pull on the cord will be too much, and it will slip in your hand. Now, you don't totally let go however. It might slip an inch or two, just barely enough so that the force of your hand holding it once again overcomes the force of the pull in the cord - but there is still a lot of tension in the cord. When the car moves away far enough again, there will be another slip of a small distance again and again.

This is how fault lines work. When there is a quake, it doesn't go back to a neutral point. It goes back to a point which is lower than the critical point that caused the earthquake.

Re:It would have likely occurred anyway

[Anonymous Coward]

Suggest you better research the coffee spill incident. Car wasn't moving, complaints about temp filed more than once, much hotter than surrounding area restaurants, woman required skin grafts to repair damage and only sued for cost of medical bills after McD's blew her off. Lots of details glossed over concerning that incident but considering just how hot it was and the damage it did I don't think awarding ONE day's worth of coffee sales was that bad of a restitution... and that was later overturned.

There are certainly shitty lawsuits but THAT one was pretty deserved I think and a poor example despite your trying to be funny about it.