It was like Armageddon. No, really. It was just like the movie. A meteorite the size of Table Mountain (as opposed to the size of Texas*) hit a huge inland lake around the area where Vredefort is now about three thousand million years ago.
The effect was that of multiple atom bombs going off. It was Hiroshima, but vastly more destructive. Some rock shattered, some melted, of some only powder remained. The meteorite made a hole 90 kilometres wide, and radically shifted the crust of the earth in concentric circles another 200 kilometres in diameter beyond that.
In spite of the fact that the rock landed in the water, the dust fallout from the impact covered the atmosphere of the entire planet, and remained there for four years.
In the cold darkness most plants died, then the herbivores died, and then the carnivores died. The only cold blooded animal that survived was the crocodile, which, apparently, is amazing. Some small rodents and other warm blooded minutiae made it as well.
There was a sort-of-an ice age, long before life as we know it existed.
A thousand million years later, almost the same thing happened in the Yucatan peninsula in Mexico. Bam wham thank you m’am, and life as it was, was over, again. There have been other such events. And I think one can reasonably assume that there will more.
A recent BBC documentary made the point that, as human beings, we are not actually busy destroying the earth. We are simply making it uninhabitable for our own race. Regardless of the consequences of our actions the earth will be here, and it would seem, absolutely fine, long after we have gone. The natural disasters that the earth, and life on it, have survived WAY surpass anything we can concoct by not recycling glass and plastic in a world economy driven by fossil fuels.
(Just out of interest, at this juncture, is anybody other than me impressed by the fact that you can score more carbon brownie points by simply eating local brie than by eschewing the driving of a gas guzzler? Continue reading