New paper: Long-lived Explosive Volcanism on Mercury

Bright deposits around a 400-km long line of explosive volcanic vents on Mercury, including in the southwest the youngest known crater hosting explosive volcanism on the planet, Kuniyoshi, less than 1 billion years old.

My new paper showing explosive volcanism as recently as a billion years ago is now in press with Geophysical Research Letters!

This is big news – most volcanism on Mercury occurred around 4.1 – 3.5 billion years ago and though it’s possible some minor lava flows are more recent, there are problems with dating these. My new research shows that volcanism definitely continued through most of the lifetime of the planet!

I’ve also compared this to what we know about the Moon. It seems that volcanism had a similar duration on the two bodies, but the nature of the most recent volcanism seems to differ. On the Moon, we see lava flows as recent as a billion years old, but so far it seems explosive volcanism lasted longer on Mercury. While our incomplete knowledge of the ages of deposits on the two bodies means we have to take this with a grain of salt, if true it may mean that magma ascent was easier on the Moon during this period (so gases didn’t build up before eruption) and/or that more volatiles are present in Mercury than the Moon.

Kuniyoshi, a fresh crater on Mercury that is less than a billion years old, with volcanic vents in its rim and wall (white arrows).

A nice little wrinkle to the story is that it was me who named Kuniyoshi, the billion-year-old crater that shows that this recent volcanism occurred. Utagawa Kuniyoshi was a Japanese woodblock artist who had a penchant for drawing cats: