#Craters Archives – THE PAGE TURNS

May 1, 2024May 2, 2024

Y is for Yucatan

The Big One! Asteroid impact site in Chicxulub, Yucatan. Graphic from *Atlanti*c.

BOOM! or maybe it was boom…boom…fshhhh..whap booma-booma…boom..bubble boom glub glub Boom…

Which was it? Luis Alvarez had one story, and he was laughed out of the paleontologist’s room. Until he wasn’t. Gerta Keller, who disagreed with him, has been laughed out of the same rooms. She’s won prizes for her research. Can they both be right?

There are multiple stories here. First, there is a story of a scientist who had a crazy idea and some data, which took decades for scientists to confirm. Then, there’s a second story, of a scientist still fighting for her own version, one which would upend those decades. Plus, there’s the underlying story, of what killed off all the dinosaurs. Between story one and story two, there’s still uncertainty about story three.

It’s been called “The Nastiest Feud in Science.” It’s still ongoing, even though now they do know where the asteroid hit. The crater is in the Yucatan.

April 15, 2024April 16, 2024

K is for the K-Pg Boundary

An image from a simple Google search for “dinosaurs.” From earthspacecircle.

You probably have heard about the asteroid. Big BOOM. You can’t really look at a generic picture of dinosaurs on the Interwebs without seeing them fleeing from hellfire and brimstone. But the asteroid involves two parts. The latter part is what happened after the BOOM, and I’ll tell that story toward the end of the alphabet. You’ll have to guess what letter.

But the first part of the scientific part of the story is how did they know? How could scientists tell that there was a big giant asteroid that eliminated all the dinosaurs? Maybe they could figure out from the fossil record that the dinosaurs disappeared. But how did they know it was caused by an extraterrestrial event? Particularly when the impact crater was, as it turns out, deep under water?

They didn’t know at first. The scientific method triumphed in the end. And fathers and sons.

The Old Ideas of Catastrophe

Before 1980, paleontologists did know that dinosaurs disappeared, around 64 million years ago, in fact. The end of the Cretaceous period was set at 64–and not 100 or 150–precisely because that was when all the dinosaur fossils disappeared. It was somewhat handy that it happened during a chalky geological period since that made it easy to spot on the sides of cliffs.

The layers of geology. White is the KT boundary. Graphic from geowyoth.

June 25, 2021July 20, 2021

The Dino-calypse: Mexican, Ukrainian, or the Hindu God Destroyer?

The traumatized pachycephalosaurus! Photo from cdn.mos.

If you think I’m nuts about the Olympics, you should hear me talk about dinosaurs. All anyone needs to say is “antorbital fenestra,” and I swoon. Or “Chicxulub crater,” which is the impact site for the theoretical asteroid that hit 65 million years ago and wiped out most of life on earth, except for the tree shrews, from which all of us are descended. (We’ll have to save the tree shrews for another time.)

So you can imagine my excitement upon learning of the controversy between the Boltysh crater and the Chicxulub crater. Which came first? Apparently, there’s big money in being first because scientists from India are also claiming precedence.

Also, I learned the word “palynological,” which satisfies my Weird-Word-of-the-Month fetish. It means “the study of live and fossil spores, pollen grains, and similar plant structures,” from the Greek palunein, which means “to scatter” as in dust or “pollen.” Fern spores are very much in play here. And, for those of you with allergies, you now know that they are palynological.

Ok, so these dudes back in 2010 noticed this crater in the Ukraine called the Boltysh crater. The crater was “roughly” the same age as Chicxulub, and when we’re talking 65 million years, roughly can be mean +/- a million years, right? They were trying to be a bit more precise—in the 10,000 year range maybe—to see whether Boltysh came before or after Chicxulub.