by Dr. David Kring
An impact cratering event, like the one that produced the Barringer Meteorite Crater, is a tremendously explosive event that crushes, melts, and even vaporizes a portion of the Earth's crust. In the case of the Barringer event, David Roddy calculated that over 175 million tons of rock were excavated to form the impact crater.
The incoming iron asteroid that caused the explosion was also dramatically altered, although a small portion of it survives in the form of solid fragments that rained down on the landscape around the impact site out to distances of 9 to 10 kilometers. Because these are surviving relicts of an asteroid, they are called meteorites. Meteorites are named for nearby geographic features and, in this case, they are named after the nearby Canyon Diablo. Some of the Canyon Diablo meteorites are immense, weighing over a 1000 lbs.
Spherules of metal were also collected around the impact crater. These spherules are about 1 millimeter in diameter and were produced when part of the asteroid was melted. This molten material was ejected from the crater in a spray of droplets that landed on the surrounding landscape.
Most of the asteroid, however, was destroyed by the blast. New computer simulations of the impact event by Elisabetta Pierazzo indicate most of the material that was lost was melted and then disseminated in an expanding cloud of very fine debris that was much smaller than the millimeter-sized droplets. In the past, it was thought this material had been vaporized. It now appears it was obliterated in a very fine, nearly atomized mist of molten metal.
Most of this finely-disseminated material came from the leading edge and interior of the iron asteroid when it collided with the Earth. Previous analyses of Canyon Diablo meteorites by Dieter Heymann and others indicate the surviving solid portions of the iron asteroid came from the rear (or top) edge. These meteorites represent a layer of material from the outermost 1 to 2 meters of the asteroid. In addition, recent analyses by Christoph Schnabel and his colleagues indicate the millimeter-sized melt spherules came from a similar to slighter deeper layer in the asteroid, again from near the trailing surface of the asteroid. Not surprisingly, the front end of the asteroid suffered the most damage in the collision and the surviving material came from the rear of the asteroid.
Hand Built for maximum Impact by The Cyrus Company. 1998.