What we can tell is something about the age of the surface that the lavas build around the volcanoes. All of Io's surface is young in planetary terms because we don't see any impact craters. Maybe in a few years he will be old enough to help me in field work. So, there are no volcanoes on Jupiter. We don't know what the oldest volcano on Io is - it's not possible to tell because most of them are still active and we don't see impact craters.
Craters are a good measure of how old a surface is.
I became interested in planetary geology while I was studying astronomy in college. He was a volcanologist and he took me to Mt. Etna to help him out. I have loved volcanoes ever since. The volcanoes on Io send particles out in space, mostly sulfur and oxygen. I work with a team of people, we do different parts of projects.