The Barringer Crater

Want to stay on top of all the space news? Follow @universetoday on Twitter

The Barringer Crater was the first confirmed asteroid crater on Earth. It is sometimes called Meteor Crater, Canyon Diablo, and the Arizona Crater. The impact event happened between 20,000 and 50,000 years ago. So, it is a fairly recent event in the Earth’s history. The cause of the crater had been a source of discussion for many years until parts of the meteorite were found. These fragments allowed D.M. Barringer to prove his claim that the crater was caused by a space object.

From the beginning the Barringer Crater was thought to be derived from volcanic action. In 1891 Grove Karl Gilbert, then the chief geologist for the United States Geological Survey, investigated the crater and concluded that it was the result of a volcanic steam explosion. He thought that if it were an impact crater it would have most of the material that was disturbed on its rim along with pieces of the meteorite. He also assumed that there should be some sort of magnetic anomaly in or around the crater.

In 1903 Daniel Barringer obtained a claim on the land from the government. His company, the Standard Iron Company investigated his claim that the Barrington crater had been made by an iron metallic meteor. Barringer’s arguments were met with skepticism, because there was a reluctance at the time to consider the role of meteorites in Earth’s geology. It was not until 1960 that research by Eugene Shoemaker would confirm Barringer’s hypothesis. The key was the presence in the crater of the minerals coesite and stishovite, rare forms of sand found only where quartz rocks have been severely shocked by an instantaneous overpressure. That over pressure can’t be done by a volcano. Only an impact event can do it.

The meteorite that struck the crater is officially called the Canyon Diablo Meteorite. Every fragment of the meteorite is officially labeled and bears the Canyon Diablo name. The name comes from Canyon Diablo, Arizona, which was the closest community to the crater when scientists began investigating the area in the late 1800s.

The Barringer Crater has been one of the most difficult impact craters on Earth to get identified. Once science accepted that coesite and stishovite are definite signs of an impact event, many craters have been designated. There are now hundreds of known asteroid impact craters around the world with many more waiting for their designation.

Here are links to the Wikipedia page on the Barringer Crater as well as a link to the homepage for the crater itself. Universe Today has published a story on the crater and the worlds 10 most inspiring craters. There is also an Astronomy Cast feature on craters.

Reference:
NASA Earth Observatory: The Barringer Meteor Crater

Tagged as: Arizona Crater, Barrington crater, Canyon Diablo, Meteor Crater