Free Republic

Dallas Abbott The Fenambosy chevron, one of four near the tip of Madagascar, is 600 feet high and three miles from the ocean. At the southern end of Madagascar lie four enormous wedge-shaped sediment deposits, called chevrons, that are composed of material from the ocean floor. Each covers twice the area of Manhattan with sediment as deep as the Chrysler Building is high. On close inspection, the chevron deposits contain deep ocean microfossils that are fused with a medley of metals typically formed by cosmic impacts. snip... The explanation is obvious to some scientists. A large asteroid or comet,...

Ancient mega-catastrophe paved way for the dinosaurs, spawned Australian continent. Planetary scientists have found evidence of a meteor impact much larger and earlier than the one that killed the dinosaurs -- an impact that they believe caused the biggest mass extinction in Earth's history.The 300-mile-wide crater lies hidden more than a mile beneath the East Antarctic Ice Sheet. And the gravity measurements that reveal its existence suggest that it could date back about 250 million years -- the time of the Permian-Triassic extinction, when almost all animal life on Earth died out.Its size and location -- in the Wilkes Land...