His paper to the Association for the Advancement of Science provided the first geological description of Meteor Crater to a scientific community. Foote identified several minerals in the meteorites, including microscopic diamonds. The team collected samples ranging from small fragments to over 600 lb (270 kg). Foote immediately recognized the rock as a meteorite and led an expedition to search and retrieve additional meteorite samples. Several years earlier, Foote had received an iron rock for analysis from a railroad executive. Foote presented the first scientific paper about the meteorites of Northern Arizona. The crater had initially been ascribed to the actions of a volcanic steam explosion, because the San Francisco volcanic field lies only about 40 mi (64 km) to the West.
The canyon also crosses the strewn field, where meteorites from the crater-forming event are found. This led to the crater also being known as "Barringer Crater." Meteorites from the area are called Canyon Diablo meteorites, after Canyon Diablo, Arizona, which was the closest community to the crater in the late 19th century.
Barringer was one of the first people to suggest that it was produced by meteorite impact and the Barringer family filed mining claims on the crater and purchased the crater and its surroundings in the early 20th century. The crater was given several early names, including "Coon Mountain", "Coon Butte", "Crater Mountain", "Meteor Mountain," and "Meteor Crater." Daniel M. Meteor Crater came to the attention of scientists after American settlers encountered it in the 19th century. Discovery and investigation The Holsinger fragment, at roughly 0.8 m (2½ ft) across, is the largest discovered piece of the meteorite that created Meteor Crater, and it is exhibited in the crater visitor center. The lack of erosion that preserved the crater's shape greatly accelerated its groundbreaking recognition as an impact crater from a natural celestial body. The relatively young age of Meteor Crater, paired with the dry Arizona climate, has allowed this crater to remain comparatively unchanged since its formation. Very few remaining craters are visible on Earth, since many have been erased by erosive geological processes. Similarly, the basin of the crater is thought to have roughly 100 ft (30 m) of additional postimpact sedimentation from lake sediments and alluvium. Since the crater's formation, the rim is thought to have lost 50–65 ft (15–20 m) of height at the rim crest as a result of natural erosion. The meteorite was mostly vaporized upon impact, leaving few remains in the crater. Impact energy has been estimated at 10 megatons TNT e. About half of the impactor's bulk is believed to have been vaporized during its descent through the atmosphere. Modeling initially suggested that the meteorite struck at up to 45,000 mph (20 km/s), but more recent research suggests the impact was substantially slower, at 29,000 mph (12.8 km/s). The speed of the impact has been a subject of some debate. The object that excavated the crater was a nickel- iron meteorite about 160 ft (50 m) across. The area was an open grassland dotted with woodlands inhabited by mammoths and giant ground sloths. The crater was created about 50,000 years ago during the Pleistocene epoch, when the local climate on the Colorado Plateau was much cooler and damper. Formation Comparison of approximate sizes of notable impactors with the Hoba meteorite, a Boeing 747 and a New Routemaster bus It was designated a National Natural Landmark in November 1967.
Since the crater is privately owned, it is not protected as a national monument, a status that would require federal ownership. ĭespite historic attempts to make the crater a public landmark, the crater remains privately owned by the Barringer family to the present day through their Barringer Crater Company, which proclaims it to be the "best-preserved meteorite crater on Earth". One of the features of the crater is its squared-off outline, believed to be caused by existing regional jointing (cracks) in the strata at the impact site. The center of the crater is filled with 690–790 ft (210–240 m) of rubble lying above crater bedrock. It is about 3,900 ft (1,200 m) in diameter, some 560 ft (170 m) deep, and is surrounded by a rim that rises 148 ft (45 m) above the surrounding plains. Meteor Crater lies at an elevation of 5,640 ft (1,719 m) above sea level. The site had several earlier names, and fragments of the meteorite are officially called the Canyon Diablo Meteorite, after the adjacent Cañon Diablo. Meteor Crater or Barringer Crater is a meteorite impact crater about 37 mi (60 km) east of Flagstaff and 18 mi (29 km) west of Winslow in the desert of northern Arizona, United States.
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