What Caused a California Road to Rise and Crumble?

gizmodo.com

18 points·curtis··7 comments

Isn't this called a "slump"? I think I learned that this is simply a landslide without a feedback loop to accelerate the process. The centre of gravity for each moving mass of rock doesn't move outside its footprint, so nothing ever tips over and rather slowly squishes everything underneath.

I also remember that this process is what makes sand dunes sing. Wind builds them steeper and steeper while gravity causes them to slowly squish down, the billions of little slips resulting audible noise.

Scientists are baffled!

Oh, never mind. They pointed to the obvious landslide.

The interesting aspects of this are (a) when you say "California", people think "earthquakes", which were not a factor here; and (b) it's unusual for a landslide to push material up.

It was at the bottom of the hill. One can imagine a more dense or solid layer sitting on top of a looser layer of soil or sediment beneath it, plus the road acts to hold it all in place like a suture. As the land slide from above pushes downwards into the lower layer, the firmer layer above will move upwards until it breaks.

It's unusual, but hardly something that boggles the mind or deserves the headline provided.

Or creating the road removed support or, more likely imho, made changes to water movements that eventually undermined the structures uphill.

Right. It's definitely interesting. I'm just tired of the "scientists are perplexed/baffled!" headlines.

They figured it out with one weird trick!

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