Friday, April 16, 2010

Rock-cycle.



Volcanic ash is made up of small particles of pulverized rock created by a volcanic eruptions. There are three ways this rock dust is formed, the one most common is the ejection of entrained particles during steam eruptions causing phreatic eruptions. The violent nature of volcanic eruptions involving steam results in the magma and solid rock surrounding the vent being torn into particles of clay to sand size.

Pulverized rock shut down flights across Europe yesterday and is likely to interrupt air travel for many more days. Who would have thought a pile of tiny specks of rock could have such a far reaching effect?

Every time we split a rock a tiny amount of dust is created. A smaller rock is created too. The masonry world is a huge industry devoted to making smaller and smaller rocks, and a lot of dust.

New rocks are not being made anywhere and the old ones are not getting any bigger.
Unless of course you count the new lava rocks being made by volcanoes.