These pictures were taken at Meteor Crater (a.k.a. Barringer Crater)
in northern Arizona on December 26, 2010.
Meteor Crater
is private land owned by the Barringer family,
not a national or state park.
It amazes me when other tourists look at this and I hear them ask whether
it's natural or man-made.
Suffice it to say, it's natural.
It was formed in a meteor impact about 50,000' years ago.
The meteor came in from space so fast that it mostly evaporated or melted
in a violent explosion, comparable to a 20 megaton hydrogen bomb.
The crater is 1.2 km or 0.8 mile across.
The tour guides like to quote figures comparing it to a stadium -
it's big enough for 20 football fields on the bottom and
seating for 2 million around the sides.
Like many impact sites, Meteor Crater was the subject of debate among
geologists for decades.
In 1891, back when geologists didn't believe meteor impacts
even happen on Earth,
the site was visited by USGS chief geologist Grove Karl Gilbert.
He assumed that a meteor would have to be as big as the crater.
And there wasn't enough ejected material to account for it.
So he concluded it was caused by a volcanic steam explosion.
Then in 1903, mining engineer Daniel Barringer thought it may still be
an impact site, and made a mining claim on the site.
The lack of any volcanic rocks on the site was one clue.
He expected a giant meteor could be mined for iron to sell to the railroads.
He died after 26 years of mining the site, having found some geological
evidence that it was an impact and that the meteor was neither intact nor
as large as he hoped.
In 1960, geologist Eugene Shoemaker finally found scientific proof that
Meteor Crater was indeed an impact site.
It turns out that the speed makes all the difference in the explosive energy -
an asteroid or comet tends to be 1/10th the diameter of the crater it leaves.
Overturned rock layers in the ejecta field and high-pressure shocked minerals,
both of which had also been found in the nuclear test craters in Nevada,
became the proof that a meteor explodes violently on impact due to the
extreme speed that it comes from space.
These things in common between nuclear and impact craters are vastly beyond
the pressure any volcano can produce.
And so the science behind recognition of impact craters was born.
Meteor Crater was the first ever confirmed impact crater on Earth.
Today
178 impact structures
have been confirmed around the world,
with
hundreds more under study.
I had been wanting to return to see Meteor Crater for years.
I was able to make a 30 minute stop at Meteor Crater during the
return
trip from Oklahoma in 2002
where I was with a group who flew some weather balloons for the dedication
ceremonies of the Oklahoma Spaceport.
But much increasing my interest in the topic, I have been learning about
the science of recognition of impact craters since 2007.
I originated a theory, still under study, of a
potential
impact site at Nevada's Black Rock Desert.
Unlike Meteor Crater, which is relatively recent (50,000 years)
in geological terms, at Black Rock the proposed impact structure is
like many old and eroded impact structures where you can't see a crater
any more. But the traces of evidence remain in the rocks.
All pages and images on this site are copyright (c) Ian Kluft
unless explicitly indicated otherwise.
Permission is required to use my images, and usually available if you ask first.
These pictures were taken at Meteor Crater (a.k.a. Barringer Crater)
in northern Arizona on December 26, 2010.