The Rust Belt was the name for the band of (largely ruined) habitats orbiting Yellowstone.
When the Melding Plague first emerged the Glitter Band -- the ten thousand pristine habitats that orbited Yellowstone -- remained intact far longer than their terrestrial cousin, Chasm City. Unfortunately, that was not to last. Eventually a handful of orbitals were infected and destroyed, and their destruction was the catalyst that brought about the ruin of the rest. As infected pieces of former habitats were thrown throughout the Band, a cascade effect was initiated that only a fraction of it weathered.