liquefaction
greengabbro | March 2, 2009Once again it is time to acknowledge that I will never read all of the papers I've flagged in my RSS reader... but I can at least go through the abstracts. While my summaries here may be slightly in error due to the fact that I haven't actually read the papers in question, here is what I'm skimming:
Clay might trigger earthquakes - Many clay minerals break down, when heated, to produce H2O + different clay minerals. If this water is produced inside a clay-lined fault zone, and not allowed to leave, it might weaken the fault enough to produce an earthquake (cf. the beer can experiment).…
greengabbro | March 21, 2008 So sand is just little weensy rocks, anyway. And this is a weensy volcano made of sand, in Peru. It’s about a meter (0.33% 0.9% of a football field thanks LL!) across.
Normally, layers of sand and silt underground bear the weight of whatever’s on top of them through a network of contacts between individual soil grains. During an earthquake, this network is disrupted. But the stuff on top is still there, bein' all heavy. Wacky hijinks ensue!
If the jiggling sand happens to be wet, all that overburden pressure is transferred to the water. Water, being incompressible, is not happy about being…