Meteor Crater Arizona

San Francisco Peaks west of Meteor Crater
50,000 years ago a vast unbroken plain stretched for miles east of Flagstaff. An iron-nickel meteorite weighing several hundred thousand tons and about 150 feet across hurtling at about 26,000 miles per hour slammed into this Arizona plain with an explosive force greater than 20 million tons of TNT. The meteorite disintegrated during impact through vaporization, melting and fragmentation leaving behind a crater 700 feet deep and over 4,000 feet across.

Meteor Crater
In the 1890s the chief geologist of the US Geological Survey concluded the crater was of volcanic origin. This idea held for two decades.

Cross section of Meteor Crater
From 1902 to 1929, Daniel Barringer, a mining engineer who believed that a meteor impact created the crater attempted to find a giant meteorite to mine the iron from. A decade later, and after Daniel’s death, the Barringer family partnered with the surrounding Bar T Bar Ranch and built facilities to provide views of the crater to the public.

Ruins of original visitor center

Raven's nest in old observatory tower
Finally in 1960, Dr. Eugene Shoemaker an astrogeologist, proved that the crater was created by a giant meteor impact. Later Shoemaker and others discovered two new minerals at the crater, coesite and stishovite. Both of these are created under extremely high pressure and had not before been identified in nature. They have now been discovered at other geological features called astroblems.

Current visitor center
Apollo astronauts trained here prior to landing on the moon because of the similar terrain. They learned that ejected material found on the rim often originated below the crater’s surface. In 1968 Meteor Crater was designated a Natural Landmark.

Visitor center courtyard and crater rim trail
Craters are clearly seen on our moon and other planets. Most impact sites on Earth have been leveled by erosion. Meteor Crater is not the largest impact site but is has sustained very little erosion.

The wind was gusting up to 45 miles per hour and the guided mile walk was cancelled. Thank goodness for hand rails on the observation areas or I might have been blown into the crater. You are not allowed to hike into the crater, or gather rocks.

From the brochure: “The vast floor of the Crater is large enough to accommodate 20 football games being played simultaneously as over two million fans watch from the sloping walls of the impact site!”

All the technical information comes from the Meteor Crater brochure, I’m no astrogeologist, yet.

Next stop Walnut Canyon National Monument.