Buried deep beneath the sleepy oil patch of Ames, Oklahoma, lies a massive, circular scar left by a celestial collision. For decades, scientists confidently pinned this impact at roughly 467 million years old, slotting it neatly into a prehistoric lineup known as the Ordovician Meteor Event. That timeline just shattered.
Researchers at the University of Texas at Austin recently took a fresh look at the Ames impact structure using advanced zircon dating techniques. The results completely rewrite the history books, proving the crater is actually about 370 million years old. That is nearly 100 million years younger than generations of geologists assumed. If you enjoyed this post, you might want to look at: this related article.
When a massive space rock slammed into North America, it didn't just alter the local topography. It carved out a treasure trove of hydrocarbons that eventually turned the Ames structure into a major oil and gas-producing region. But figuring out when the impact happened turned out to be a massive scientific puzzle.
Geologists originally dated the site using biochronology. By analyzing rock cores, they found fossilized teeth belonging to conodonts—ancient, eel-like creatures that lived during the Ordovician period. Because those fossils matched the era, researchers assumed the impact must have happened at the same time. For another perspective on this development, refer to the latest update from NASA.
Lead author Elizabeth Catlos and her team found the fatal flaw in that logic. Those tiny fossilized teeth were already millions of years old when the asteroid hit. The catastrophic impact simply churned up ancient sediment, mixing older biological debris into the wreckage.
To clear up the confusion, the research team extracted zircon crystals from the Ames rock cores and performed uranium-lead dating. No matter how many times they ran the tests, the geochemical signature kept pointing to the Devonian period, specifically around 370 million years ago.
Teaming up with NASA scientists, the team used specialized imaging to look for microscopic shock pressures baked inside the zircon crystals. These microscopic deformations act as a permanent clock, recording the exact moment an asteroid strike scrambled the mineral's atomic structure. The evidence confirmed the younger date without a shadow of a doubt.
Moving the Ames impact from 467 million years ago to 370 million years ago completely upends theories about ancient Earth history. Previously, scientists used Ames as a major anchor point for the Ordovician Meteor Event—a wild period in Earth's history when geologists theorized the planet might have possessed a ring of asteroid debris similar to Saturn.
By pulling Ames out of the Ordovician timeline, scientists have essentially removed a major pawn from that theory. Instead, the impact now sits right on the doorstep of the Frasnian-Famennian mass extinction, which wiped out a massive percentage of marine life around 372 million years ago.
This new timeline forces researchers to rethink what caused that ancient extinction pulse. Was it driven entirely by internal forces like massive volcanic eruptions, or did an unexpected visitor from space deal a devastating blow to a struggling ecosystem?
Getting planetary timelines right matters. If we want to understand how Earth recovers from global catastrophes, we need an accurate calendar of events. The Ames crater proves that even well-established geological models can crumble when smarter technology enters the lab.
Take a closer look at how past studies rely on fossil mixing. If researchers don't verify dates with mineral-level geochemistry, history remains full of blind spots. Geologists now have a blueprint to re-examine impact sites across North America to see what else we've got wrong.
