26 August 2011

Sexy Geology: Accretionary Wedge #37

Posted by Jessica Ball

Lockwood at Outside the Interzone wants to know what gets a geologist all shook up. (Hint: it’s not just earthquakes.)

Several hours of hiking on an exotic tropical island + one active cinder/spatter cone + standing on the exact spot where a fissure eruption started, that’s what! (This would be the “Harry Potter” fissure eruption of July 2007 at Pu’u O’o on Kilauea, which I saw during my stint with the University of Hawai’i at Hilo’s CSAV summer field camp in volcanology.)

Look at that spatter! Look at that ground crack! Look at that beautifully iridescent new rock! *Swoon*

Earlier in my undergrad years, I probably would have answered with a beautiful example of a structural feature, those being more common in Virginia than volcanoes. But after junior year, my affections were diverted by the allure of molten rock.

Just above the opening of the fissure on Pu'u O'o's eastern flank (and looking out over the active flow field to the right)

There’s something about volcanoes that just gives me the shivers and gets my adrenaline pumping all at the same time. A fissure like this is a direct connection to what’s going on inside the Earth – how could anyone not be excited about that? Not to mention, hey, that rock was flowing.

A huge lava flow started with this one little "crater"

I think one of the most profound things I feel when I see something like this is that I’m seeing a concrete point in the rock cycle – this is where and when a rock starts. It doesn’t get any more primal, really. Someday this lava could be grains of sand on a beach, or metamorphosed in the core of a mountain chain, or soil anchoring a forest, but right here, it’s the newest thing around.

Top of the fissure

Yeah, I find that pretty darn sexy.