Most of the energy can propel lots of ground into the air, which rains down upon the surroundings in a thick blanket of heated, even molten, rock. Tektites are probably produced this way, although some experts also consider the Moon as a possible secondary source. This requires truly spectacular impacts of kilometer-sized bodies. There are only four known tektite fields on Earth: North America (33 million years), Czechoslovakia (15 million years), Ivory Coast (1 million years) and Southeast Asia/Australia (700,000 years or less).
This answer was updated in 2011.
See my books:
The Astronomy Cafe (1998) and
Back to the Astronomy Cafe (2003) for more FAQs in printed form. Author: Dr. Sten Odenwald, Copyright 2011
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