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The Day Life on Earth Almost Died

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A Piece of the KT Boundary

Around the end of July, I wrote a post entitled Revisiting the Cretaceous Extinction. This week, I read a fascinating story entitled “The Day the Earth Died” in the April 8, 2019 issue of The New Yorker. The asteroid that collided with Earth around 65 million years ago was at least six miles wide and gouged a crater about eighteen miles deep and launched 25 trillion metric tons of debris into the atmosphere. The article goes on:

The damage had only begun. Scientists still debate many of the details, which are derived from the computer models, and from field studies of the debris layer, knowledge of extinction rates, fossils and microfossils, and many other clues. But the over-all view is consistently grim. The dust and soot from the impact and the conflagrations prevented all sunlight from reaching the planet’s surface for months. Photosynthesis all but stopped, killing most of the plant life, extinguishing the phyto-plankton in the oceans, and causing the amount of oxygen in the atmosphere to plummet. After the fires died down, Earth plunged into a period of cold, perhaps even a deep freeze. Earth’s two essential food chains, in the sea and on land, collapsed. About seventy-five per cent of all species went extinct. More than 99.9999% of all living organisms on Earth died, and the carbon cycle came to a halt.

This massive disaster left a signature layer across the entire surface of the planet referred to as the KT boundary, short for Cretaceous-Tertiary. (It is also referred to as the KPg boundary after the Tertiary was renamed the Paleogene by geologists.) This boundary layer is high in the rare element Iridium, which is most often found in meteorites and asteroids.

It is a sobering thought that an object from space only six miles across (10 km) could strike the Earth, which is eight thousand miles across (12,900 km) and end up killing virtually all life, and certainly annihilating the human race.

The asteroid collided with the Earth around Chicxulub on the Yucatán peninsula, which I plan to visit, hopefully with a geologist, early next year.

Revisiting the Cretaceous Extinction

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This Yucatán Fishing Village Along the Gulf of Mexico Hides a Secret

A few miles from Progreso, Yucatán, is the fishing village of Chicxulub (CHEEK-shoe-lube) which was the site of one of the great catastrophes in the life of the earth. Some 65 million years ago, an asteroid that was nine miles (fifteen kilometers) across slammed into Chicxulub at the speed of 44,640 mph (or 20 km/second) and destroyed some three quarters of all the life on earth, including all the dinosaurs. The impact was equivalent to a million times larger than the largest hydrogen bomb explosion and created a crater that was sixty miles (100 km) across and eighteen miles (30 km) deep.

Of course, that was millions of years ago, and the geology of the area has changed significantly.

Where the Asteroid Impacted

 

Signs of the Impact Today: A Ring of Cenotes

Today, the Yucatán Peninsula is a large limestone chunk that has been raised up, but with numerous underground rivers and caves admitting access to the water beneath. What you will not find there a river. This did not make it easy for the ancient Maya to grow crops—except in their areas where cenotes prevail. The dark green aresa beneath the ring of cenotes is where the Puuc Hills are located, which rise to an elevation of several hundred feet. There, the Maya dug cisterns, called chultunes, which frequently run dry during periods of drought.

I hope to visit Chicxulub Puerto when I stay in Merida or Progreso.

 

The Dinosaur and the Flickers

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Changing Tastes Affect Whole Media

Changing Tastes Affect Whole Media

Yesterday at Cinecon 51, I had an interesting discussion with a film memorabilia vendor from Philadelphia about the changing tastes of the film audience. Both of us noted that there was a remarkable lack of younger filmgoers—anything under age forty—attending the recently restored films from former decades. In fact, most of the attendees were in their seventies or above.

That set me to thinking: I am happy that I did not achieve my educational goal of becoming a professor of motion picture history and criticism. If I had, I would have had to face the fact that my chosen field was, essentially, ultimately doomed for lack of interest. How many younger people would be interested in silent films, or early talkies in black and white, or even anything that had a more complicated story line. Who would even be able to sit still for The Seven Samurai or Doctor Zhivago or Rules of the Game?

People are clearly becoming more distracted as time goes on. Movie screens have gotten smaller, and home TV screens have grown larger. They haven’t quite met yet, though the tendency continues. One does not need to watch a television with rapt attention, not while one is texting, reading one’s e-mails, or watching YouTube on a smart phone.

So, if I were a professor of film history, I would feel as if I were ramming films down the throats of a younger generation that thought the subject matter was irrelevant.  Who cares about the films of F. W. Murnau, Josef von Sternberg, or even Alfred Hitchcock?  (I can just imagine trying to explain Hitch’s Vertigo or Shadow of a Doubt to a restive crowd who were itching to jump onto their smart phones.)

As far as my own tastes are concerned, I will follow them through à l’outrance, to the bitter end. The films I love, I will always love and continue to study, even though it separates me from the following generations. Does that make me a dinosaur? So be it!

Land of Dinosaurs

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Exhibit at Trelew’s Museo Paleontológico Egidio Feruglio

Exhibit at Trelew’s Museo Paleontológico Egidio Feruglio

The first book I ever read about Patagonia was George Gaylord Simpson’s Attending Marvels: A Patagonian Journal, about the paleontologist’s search for dinosaur bones in that windy desert that forms most of Argentina’s South. A sparsely populated country (less than one person per square mile), Patagonia preserves its paleontological heritage better than most populated places.

Near Nequén, there are three active digs that a tourist can visit. In Trelew, there is the attractive Museo Paleontológico Egidio Feruglio. Even the airport at Trelew has dinosaur bones on display.

Last September, CBS announced the discovery of substantial dinosaur remains for Dreadnoughtus schrani, which lived 77 million years ago, measured 85 feet long, and weighed in at 65 tons—heavier than a Boeing 737. (I wonder whether it was a vegetarian.)

I probably will not spend much time digging for fossils on my next trip to Argentina, but it’s always fun to see what others have dug up in that desolate land.