Awesome concept! Makes me think of the fossils they find of dinosaurs locked in combat.

For names, one of the first things that comes to my mind is something like Wyrmfall. If that's not your vibe, I suggest looking at the names of surface features of the volcanic moon Io for inspiration, or locations in Hawaii Volcanoes National Park and their associated legends. But also, "It Still Burns Where They Fell" sounds pretty dang cool!