Meteor Crater, AZ
2005 Chautauqua Short Course:
Cosmic Collisions with the Earth:Chicxulub, Meteor Crater and More.
Meteor Crater, AZ, was formed approximately 50,000 years ago, at least 35,000 years prior to any human occupation of the North American continent, by the impact of an iron/nickel meteorite approximately 150 feet (about 50 meters) in diameter. The meteorite hit the surface of a relatively flat plain at about 30 to 40 thousand miles per hour, releasing about 20 megatons of energy, lifting the crater rim about 150 feet, and excavating a crater about 4000 feet in diameter and 700 feet deep. About 1/3 of the crater filled with material washed down the crater sides and with lake sediments, but the floor is still about 550 feet (about the height of a 60-story building) beneath the crater rim.
I am standing on the red Meonkopi sandstone, which forms the uppermost lip of the crater. Beneath the Meonkopi sandstone is a thin bed of Kibab limestone, and that is underlain by the Coconino sandstone, which forms the bulk of the crater. The Coconina sandstone is a bright white formation.
The view above shows about 180 degrees of the crater, as seen from the north looking south. This panorama of seven pictures is taken from an upper observing platform of the visitor center / museum. Some people can be seen on a lower observing platform along the right edge of this panorama.
The view above shows about 180 degrees of the crater, as seen from the south looking north. The roof of the visitor center / museum can be seen along the crater rim just left of the crater center.
Click for other meteorite impact sites I have visited: the Mecatina Crater (Canada), the Reis Crater (Germany), the Chicxulub Crater (Mexico), and photos from my 1969 visit to this (Meteor Crater, AZ) impact site.