TanzaniaOklahoma Crater 100M Years Younger
New zircon dating suggests Oklahoma’s Ames crater is about 100 million years younger than thought and may date to the Late Devonian, tying it to a mass extinction event that wiped out 40% of marine life. The crater's revised age is around 370 million years, according to researchers led by the University of Texas at Austin.
Global Newsflix 2 min read
Researchers led by the University of Texas at Austin found a population of zircons dated to about 369.7 million years ago, placing a major high-temperature event at Ames in the Late Devonian instead of the Ordovician Period.
The Ames impact structure, a 14- to 16-kilometer-wide crater beneath the town of Ames, had generally been placed in the Ordovician Period around 470 million years ago.
The traditional age of Ames came largely from conodonts, tiny tooth-like fossils from extinct marine animals found in sediments associated with the crater.
The new work offers another possibility: the meteorite may have struck rocks that already contained Ordovician fossils, excavating and redepositing them inside the crater millions of years later.
The study, published in Meteoritics & Planetary Science, does not yet provide an unquestionable impact date, and the authors consider the zircon results the strongest evidence so far that Ames is much younger than previously assumed.
The revised chronology removes Ames from a group of craters used to support the hypothesis that Earth may have possessed an asteroid-debris ring during the Ordovician.
The new age overlaps the broader interval of the Frasnian-Famennian mass extinction, but researchers stress that more dating is needed before connecting the Ames impact directly with that biological crisis.
Key facts
- Oklahoma’s Ames crater is about 100 million years younger than thought
- The crater's revised age is around 370 million years
- The crater may date to the Late Devonian
- The mass extinction event tied to the crater wiped out 40% of marine life
Three perspectives
Neutral
The discovery of the crater's revised age has significant implications for our understanding of Earth's history. Further research is needed to confirm the connection between the Ames impact and the mass extinction event. The study's findings will be closely watched by the scientific community.
Positive
The new research provides a major breakthrough in our understanding of the Ames crater and its potential connection to a mass extinction event. The discovery could lead to new insights into the Earth's history and the impact of asteroid collisions on the planet's ecosystem.
Negative
The revised age of the Ames crater raises questions about the accuracy of previous research and the reliability of dating methods. The lack of conclusive evidence linking the crater to the mass extinction event is a limitation of the study, and more research is needed to fully understand the implications of the discovery.
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