3Bar, what YouTube video are you talking about? The strange thing about that Ginguro video is that they never mention that the Vredefort structure (site of Witwatersrand deposits) and Sudbury are both gigantic, very old impact structures (meteorite impact structures). Guess they didn't want to sound like kooks talking about meteors. I'm not clear if there is some causal relationship between the witwatersrand deposits and the impact. Should look into that.