California's Hidden Doomsday (S01E06)
S01E06
Rob Nelson travels to California to delve into a web of significant fault lines that could trigger an unprecedented mega-quake. His journey then takes him to a puzzling sinkhole, which many speculate might be a bottomless chasm leading straight to the Earth's core.
Show
Secrets of the Underground
Episode
S01E06
Air Date
Mar 21, 2017