Surprises in the Chicxulub Tale of Dino Extinction
Did an asteroid hit in the Yucatan explain the demise of the dinosaurs? New drilling in the crater has brought some surprises.
The Alvarez theory of an asteroid impact causing the extinction of the dinosaurs 66 million years ago, embraced reluctantly at first, has taken on the feel of accepted truth, especially after a “smoking gun” crater was found. Chicxulub in the Yucatan is assumed to be ground zero where a San-Francisco-sized object at the right time, leaving a quasi-circular scar part onshore and part offshore. It would have raised tsunamis far and wide, and lofted smoke into the atmosphere, cooling temperatures for decades. Some 76% of organisms are said to have perished immediately after that unlucky day for planet earth. Or so, that’s the typical story.
Now, published results from new drill cores recovered offshore from part of the crater’s peak ring have scientists wrinkling their brows. Some things are not what they expected. “Life recovered rapidly at impact site of dino-killing asteroid,” NASA’s Astrobiology Magazine says, noting one of the main surprises. Inferring ecological signals from smaller impact craters, geologists thought they had a handle on how long it takes life to recover from a really big impact site. Other impact scars, they say, took ten times as long to recover.
Although the asteroid killed off species, new research led by The University of Texas at Austin has found that the crater it left behind was home to sea life less than a decade after impact, and it contained a thriving ecosystem within 30,000 years — a much quicker recovery than other sites around the globe.
Microfossils and ichnofossils (such as burrows) show that animals re-inhabited the scar in as little as two to three years after the impact. How could such a catastrophe kill off all dinosaurs around the world, yet allow living things to invade the site so quickly? Is it because tsunamis rebounded, bringing in fresh material from a distance?
“We found life in the crater within a few years of impact, which is really fast, surprisingly fast,” said Chris Lowery, a postdoctoral researcher at the University of Texas Institute for Geophysics (UTIG) who led the research. “It shows that there’s not a lot of predictability of recovery in general.”
Another piece on Astrobiology Magazine says that forests and tree-dwelling birds were decimated around the planet by the impact, too. Is it plausible that “recovery after a global catastrophe could be a local affair”?
The paper in Nature concludes that “proximity to the impact did not delay recovery and that there was therefore no impact-related environmental control on recovery.” This counter-intuitive result flies in the face of common sense that destruction should be worst near the crater.
The impact seems to have generated a system of hydrothermal vents in the crater. The authors made a brief suggestion that “Impact-generated hydrothermal systems are hypothesized to be potential habitats for early life on Earth.” That’s all it took for some reporters to speculate that impacts might have caused the origin of life.
A news feature in PNAS gives some background on the scientists who adventured to the Yucatan and lived on the drilling rig for weeks getting the drill cores. Most of the story concerns the characters and their adventures, but the article does share additional anomalies about the geology of the site. “To this day we don’t understand what the pattern of fractures was that led to those changes,” one of them says about the pulverized granite seen in the drill cores. After that, the article degenerates into rank speculation about how impacts might be “crucibles of life” on earth and other planets. Close your eyes and let your imagination take over: “You can see impacts as generating a whole set of experiments, producing lots of organic material, and then at some point you can imagine that a self-replicating molecule emerged.” Whoever says this “is not unreasonable” has not done the math like Illustra Media did in Origin (see “The Amoeba’s Journey” video clip).
Critique of the Chicxulub Senario
Promoters of the impact story for the extinction of the dinosaurs like to make it sound like the smoking-gun evidence at Chicxulub clinches the case. It takes an outsider like Brian Thomas at ICR to point out problems and ask questions. In ICR’s June edition of Acts & Facts, his timely article points out some facts that should raise serious doubts about the story. He begins by noting that even children are taught the story of Chicxulub, which leads children of Christian parents struggling to know how to reconcile the secular story with what the Bible teaches about a worldwide Flood. Here’s a summary of his responses:
- Frogs and clams are much more vulnerable to the toxic after-effects of an impact-caused extinction, but they survived fine.
- The Chicxulub crater is not circular. “Plus, an impact with worldwide destructive force would have melted rocks, but the site has very little melted rock.” Upwelling magma could explain the structure seen at Chicxulub.
- The Flood layers cover hundreds of square miles that could not have been produced by an impact tsunami, which would have created a wedge-shaped trace that decays with distance. Many flood layers stay the same thickness over vast distances and can even be seen across continents.
- Dinosaurs are found buried in mud sediments on the opposite side of the globe from the Yucatan site.
- Soft tissue in fossils of dinosaurs and other animals shows the extinction was recent; the tissues could not last 66 million years.
In the Genesis Flood scenario, some dinosaurs were taken aboard the Ark, and the rest perished. Those that proliferated for a short time after the Flood were understandably hunted down as pests or as trophies for ‘dragon slayers.’ That’s why none of the post-Flood dinosaurs fossilized, and why none survive today.
When consensus science tells a story, best look for independent thinkers. Selective evidence is easy to amass to tell a story, but one stubborn fact can knock it down. Brian Thomas just shared five, and that’s not necessarily a complete list.
Exercise: What other ‘scenarios’ or consensus stories are told by evolutionists in spite of contrary evidence? Make a list. They may have some alleged ‘smoking gun’ evidence, but contrary evidence is usually minimized or ignored. The Chicxulub story is one. Snowball Earth is another. What others can you think of?