Monday, June 14, 2010

Did the Chicxulub impactor have a BIG brother?

It is a fairly universal fact that the impactor 65 million years ago that happened off the coast of Mexico at Chicxulub played the death knell for many plant and animal species, including the dinosaurs. However there are still that remaining nagging few who say that the Chicxulub object could not have done such a devastating job all on its' own. They point to the Deccan Traps area that underwent bouts of volcanic activity between 68 and 64 million years ago. The thought is that this activity would have blocked so much of the sun's energy that most plants would have died and along with it the animals that depended on the as well.

There is however a problem. Such a large area of volcanic activity usually is attached to a tectonic plate's rim. Not so in this case. It was one of the odd hot-spot breakouts like Yellowstone or the Hawaiian island chain. But again there is a problem. These hot-spots are relatively speaking fairly small. The Deccan Traps covers a staggering 500,000 square kilometers! Weirder still, lava that makes up the Deccan Traps is high in iridium, not common in the Earth's crust but very common in yep, you guessed it.... meteorites. And such a meteorite! If the measurements are even close, we may find that the Earth was struck, at about the same time as Chicxulub, by an unbelievably huge 30km impactor!

I am only taking a small part of the really fascinating article in IO9. It reads like the best mystery novel. Check it out HERE

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