[meteorite-list] Crater excavation question

From: Sam Kimpton <bessel_at_meteoritecentral.com>
Date: Thu Apr 22 09:41:09 2004
Message-ID: <3A86219A.C72EC8B3_at_europa.com>

I was looking over the "Lunar Sourcebook" by Heiken et al. an noticed
something strange in the explanation of the cratering process on page
65.

Section 4.1.2. discusses the generation of compressional and
co-commitant
decompressional shock waves in both the target and projectile. Energy is

released along the free surfaces of both. This is standard theory and I
am
happy with it. What bothers me is the following statement: "Specific
Energies
of the highly compressed target and projectiles are increased upon
adiabatic
decompression after passage of the shock wave. This increase apears as
waste heat."

An adiabatic change by definition precludes a change in temperature.
How is
it possible to have energy liberation in the form of wast heat after an
"adiabatic"
reduction of pressure as stated here?

I post this in the off chance that some clever soul on this list can
elucidate on
this question.

Thanks.

Sam Kimpton
Received on Sun 11 Feb 2001 12:22:34 AM PST