The big whatsit on Mercury

What would you call this thing? It's a set of troughs on the surface of Mercury, inside its enormous Caloris basin.

What you name something is closely related to the story about it you have in your mind. "Radial troughs" is probably the most neutral name. My first impulse is to call it a "spider graben," because it looks like the result of a deep swelling from below, after which radial slivers of the crust slipped down between the adjoining crust slices—that's the "graben" part. But I might be wrong about that story. OK, I am likely to be wrong. Ok, very likely. But that's probably how I'll always think of this structure because that's what I named it. What would you call it?
_{NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington/Brown University}