Meteor Crater is a meteorite impact crater located approximately 43 miles (69 km) east of Flagstaff, near Winslow in the northern Arizona desert of the United States. Because the US Department of the Interior Division of Names commonly recognizes names of natural features derived from the nearest post office, the feature acquired the name of "Meteor Crater" from the nearby post office named Meteor. The site was formerly known as the Canyon Diablo Crater, and the meteorite that created the crater is officially called the Canyon Diablo Meteorite, the name that is on all officially labelled fragments of the meteorite. Scientists refer to the crater as Barringer Crater in honor of Daniel Barringer who was first to suggest that it was produced by meteorite impact. The crater is privately owned by the Barringer family through their Barringer Crater Company, which proclaims it to be "the first proven, best-preserved meteorite crater on earth."

Despite its importance as a geological site, the crater is not protected as a national monument, a status that would require federal ownership. It was designated a National Natural Landmark in November 1967.

Meteor Crater lies at an elevation of about 1,740 m (5,709 ft) above sea level. It is about 1,200 m (4,000 ft) in diameter, some 170 m deep (570 ft), and is surrounded by a rim that rises 45 m (150 ft) above the surrounding plains. The center of the crater is filled with 210–240 m (700–800 ft) of rubble lying above crater bedrock. One of the interesting features of the crater is its squared-off outline, believed to be caused by pre-existing regional jointing (cracks) in the strata at the impact site.

Formation of the crater

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. At the time, the area was an open grassland dotted with woodlands inhabited by woolly mammoths, giant ground sloths, and camels. It was probably not inhabited by humans; the earliest confirmed record of human habitation in the Americas dates from long after this impact.

The object that excavated the crater was a nickel-iron meteorite about 50 meters (54 yards) across, which impacted the plain at a speed of several kilometers per second. The speed of the impact has been a subject of some debate. Modeling initially suggested that the meteorite struck at a speed of up to 20 kilometers per second (45,000 mph), but more recent research suggests the impact was substantially slower, at 12.8 kilometers per second (28,600 mph). It is believed that about half of the impactor's 300,000 metric tons (330,000 short tons) bulk was vaporized during its descent, before it hit the ground.

The impactor itself was mostly vaporized; very little of the meteorite remained within the pit that it had excavated.

Geology

The impact created an inverted topography so that the layers immediately exterior to the rim are stacked in opposite order in which they normally occur; the impact overturned and inverted the layers to a distance of one to two kilometers outward from the crater's edge. Specifically, climbing the rim of the crater from outside, one finds:

*Coconino Sandstone (sandstone formed 265 million years ago)

*Toroweap Formation (limestone formed 255 million years ago)

*Kaibab Formation (dolomite formed 250 million years ago)

*Moenkopi Formation (mudstone formed 200 million years ago)

In the interior of the crater the layers are in the expected order.

credited to wikipedia