[cogitator]

It's a solidified "toe" of pahoehoe lava. As the lava extrudes in the flow, it forms "toes" (kinda like the way that an amoeba moves) as the lava moves forward. Most of the time the toes stay on the ground; for some reason this one caught some air before solidifying.

[capitan_refugio]

Nice picture. I suggest we submit an application to the USGS naming committee and designate this landmark as "Clinton's Pecker." I think, these days, he could use the publicity, with Hitlery's book and all.

[Rennes Templar]

I see, thanks. I thought it was the fossilized tail of a dinosaur covered in lava.