A Simple and Easy Math Problem

On June 13th we returned to the Cape Akrotiri lighthouse where we first looked at the domes that formed the Akrotiri peninsula. This time, Lisa wanted to show us the most massive block she’s ever seen. A block is a solidified rock that is thrown up into the air during an eruption, and can be any shape. This blocks shape was gigantic. 

We walked down the slope behind the Akrotiri lighthouse. Lisa pointed out the thin layer of pumice from Phase 1 of the eruption which consisted of pumice fall. On top of Phase 1 was the white lapilli and ash beds of Phase 2 that were deposited as a result of pyroclastic surges. Pyroclastic surges are turbulent clouds of ash and lapilli and lithic fragments that tumble across the landscape outward from the vent depositing the material according to density. Lithic fragments are usually deposited together in a pyroclastic surge because of their density. The giant block Lisa brought us down there to see was obviously too large to be carried by a pyroclastic surge. It wasn’t even close to the size of the lithic fragments carried by the surge. So how did it get there? 

Continue reading “A Simple and Easy Math Problem”

Moving Megatons: The Excavational Eruptions of Calderas

I’ve just learned the full story of the Minoan eruption. In my mind, I’m imagining 60 cubic kilometers of earth. This is about the size of a block of the Los Angeles basin, by volume; a massive amount of land. I can see all this land being ejected by the volcano miles into the sky, over a span of 24 hours. Such is the case of Santorini’s last caldera forming eruption.  Continue reading “Moving Megatons: The Excavational Eruptions of Calderas”