CompuServe Messages

Hi, Kamron– As noted in another message, I blooped in speaking of a root as deep as the mountain is high – I should have multiplied root depths by 5 or 10, since the air/rock density ration is much greater than crust/mantle density. The Scientific American of Oct 1993 article on large igneous provinces shows the Broken Ridge plateau and the 90-East ridge as being such. It implies the Kerguelen plateau and the Broken Ridge plateau formed from a single mantle plume. I take this to mean the plume formed a hot spot and erupted at the southeast Indian spreading ridge, forming something like Iceland, which was later split by the ridge. Perhaps the hotspot actually arrived quietly, built the 90-East ridge over time, then got hotter and produced the plateaus? This would be the reverse of normal hotspot arrival protocol. I also recall reading elsewhere that Kerguelen includes some continental material; perhaps a New Zealand-like fragment happened to be near the line of fire. –Doug