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Out with a Bang: The day the Mesozoic world ended 

Reuben and Caleb Anderson meet T. rex at an exhibit at OMSI in the 90s.It is always best - if possible - to turn problems

click to enlarge Reuben and Caleb Anderson meet T. rex at an exhibit at OMSI in the 90s.
  • Reuben and Caleb Anderson meet T. rex at an exhibit at OMSI in the 90s.
Reuben and Caleb Anderson meet T. rex at an exhibit at OMSI in the 90s.It is always best - if possible - to turn problems into opportunities, which is what I did recently when my poor old VW "Westy" blew her engine over in Ontario.

With my wife, Sue, the tow truck driver and yours truly stuffed in the cab, all I could do was watch a lot of beautiful Oregon go by, and read a good book.

What I choose to read is the subject for this week's column: "T. Rex and the Crater of Doom," by Walter Alvarez. The book is a revelation, right from the cover painting, which is spectacular, to the last exciting chapter about a comet striking Jupiter.

Most of the objects from outer space - such as comets and meteorites - come streaking into our atmosphere at about three meters per second, but burn up before they strike Earth. However, once every 60 millions years or so, a Big One gets through and slams into our Home Planet like a sledgehammer. The famous Arizona Meteor Crater east of Flagstaff is proof that it happens. Furthermore, it is not a question of "will it happen again," rather it's a question of "when."

That's what this marvelous book addresses. In one day, literally, some 65 million years ago - between the younger Tertiary and older Cretaceous Periods - millions of Earth's plants and animals were totally exterminated.

If the object from outer space doesn't hit smack-dab in the center of Australia, enough aborigines will survive along with a few dingos, coyotes, raccoons, cockroaches, ants, and termites to start over.

What this story is also about - in part - is the geologists who believe (passionately, I might add) that everything in the geological world happens s-l-o-w-l-y. These people are disciples of Charles Lyell's, 1830, Principles of Geology, which gave rise to uniformitarianism, as opposed to catastrophism. Back in the 1920's a studious geologist by the name of J. Harlen Bretz presented his ideas on the scablands of Central Washington as evidence of a catastrophic flood, or series of floods. The uniformitanarians laughed him out of the lecture hall. However, a decade later, further investigations proved without a doubt that, yes, gigantic floods did hammer and scoop out the scablands - along with the Columbia River Gorge - and "drowned" the Willamette Valley in the process.

Likewise it was a geologic and philosophical struggle to understand why Tyrannosaurus rex and its food supply went extinct almost overnight. The uniformitanarians claimed it didn't happen that fast, it took longer as dust and debris from volcanoes blocked out the sun and the Earth cooled.

But further evidence, such as mass extinction of tiny life forms beneath the seas, and shattered remains of melted quartz from great depths, plus radio active elements in the "KT Boundary" - a thin line of fossil-bearing rock between the Cretaceous and the Tertiary - suggested otherwise.

The big breaks came when physicists, working with geologists found evidence that the boundary between the time when the dinosaurs were the top dog, but vanished forever, suggested an enormous object from outer space slammed into the Earth, killing all the dinosaurs, along with about half of every living thing at the time.

Further research suggested the object from space hit in the ocean, penetrating the Earth's crust miles deep, and then threw so much debris into the atmosphere that sunlight was blotted out for years. Therefore, a search was started to find the crater and evidence of tsunamis of 65 million years ago. As each piece of evidence supported the giant impact on Earth was cataloged, the uniformitanarians worked harder to support their ideas of s-l-o-w changes. However, when remains of an ancient crater were discovered near the shoreline of the Yucatan, and Mexican petroleum geologists shared their collection of cores from the KT boundary with other geologists, the "theory" of a giant impact from space became "fact."

Astrophysicists suggested this was another similar event that has been going on over the last 4.55 billion years (give or take one percent) Earth has been in existence, and it will happened again.

So, how's your "Emergency Preparedness Kit" looking these days...?


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