Editing Meteor Crater (section)

===Eugene M. Shoemaker===
[[File:Barringer Crater aerial photo by USGS.jpg|thumb|Meteor Crater from the southeast; the uplift around the rim can be seen]]
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[[Eugene Merle Shoemaker]] continued investigations at the crater. A key discovery was the presence in the crater of the minerals [[coesite]] and [[stishovite]], rare forms of [[silica]] found only where [[quartz]]-bearing rocks have been severely [[shocked quartz|shocked]] by an instantaneous overpressure. Shocked quartz cannot be created by volcanic action; the only known mechanisms of creating it are naturally through [[lightning]] or an [[impact event]], or artificially, through a [[nuclear explosion]].<ref name=DRO-GS2002 /><ref>Shoemaker, Eugene M. (1987). [http://arrowsmith410-598.asu.edu/2009/Lectures/Lecture16/i0-8137-5402-X-2-0-399Shoemaker.pdf "Meteor Crater, Arizona"], ''Geological Society of America Centennial Field Guide – Rocky Mountain Section''.</ref> In 1960, [[Edward C. T. Chao]] and Shoemaker identified coesite at Meteor Crater, adding to the growing body of evidence that the crater was formed from an impact generating extremely high temperatures and pressures.  He confirmed what F.R. Moulton and H.H. Nininger already proposed: the impact vaporized the vast majority of the impactor. The pieces of [[Canyon Diablo (meteorite)|Canyon Diablo meteorite]] found scattered around the site broke away from the main body before and during the impact.<ref name="Levy">{{cite book |last1=Levy |first1=David |url=https://archive.org/details/shoemakerbylevym00levy/page/69/mode/2up |title=Shoemaker by Levy: The man who made an impact |date=2002 |publisher=Princeton University Press |location=Princeton |isbn=978-0691113258 |pages=69, 74–75, 78–79, 81–85, 99–100}}</ref>  Shoemaker published his conclusions in his 1974 book, the ''Guidebook to the geology of Meteor Crater, Arizona.''<ref name="Shoemaker1974">{{cite book |last1=Shoemaker |first1=Eugene |title=Guidebook to the geology of Meteor Crater, Arizona |date=1974 |publisher=Center for Meteorite Studies at Arizona State University |location=Tempe |pages=1–71}}</ref>

Geologists used the nuclear detonation that created the [[Sedan crater]], and other such craters from the era of [[Nuclear weapons testing|atmospheric nuclear testing]], to establish upper and lower limits on the kinetic energy of the meteor impactor.<ref>{{cite web|url=http://keyah.asu.edu/lessons/MeteorCrater/KM13.html|title=Keyah Math – Numerical Solutions for Culturally Diverse Geology|website=keyah.asu.edu}}</ref>