Heating of Renazzo matrix material: Evidence for
the presence of two distinct deuterium
Floss C., Bernatowicz T., Smolar T., Stadermann F. J. and
Walker R. (2000) Lunar and Planetary Science XXXI, Abstract
#1359, Lunar and Planetary Institute, Houston (CD-ROM).
Deuterium enrichments are common in many primitive
meteorites and IDPs, and are generally believed to have
resulted from chemical isotopic fractionations in
interstellar molecular clouds. Although D enrichments in
primitive meteorites are known to be associated with a
variety of organic compounds, other carriers may also exist,
including waters of hydration in phyllosilicates.
Furthermore, the carriers may not be identical in different
The carriers of D excesses in IDPs are even less well
understood than those in meteorites, due to the small amount
of material available, and it is not yet clear whether the
enrichments are associated with organic matter or water or
both. As noted in, identification of the D carriers in IDPs
would be simpler if it could be shown that the major
carriers are the same in both IDPs and meteorites. To
address this problem, we have initiated experiments to
determine the heating conditions under which D anomalies are
lost. Although not definitive, similar loss patterns would
provide evidence for the presence of similar carriers in
both types of extraterrestrial matter. Furthermore, such
experiments place constraints on the temperature histories
these materials have experienced.
In the initial phase of this study we have carried out
heating experiments on matrix material from the Renazzo (CR)
carbonaceous chondrite. This meteorite is of particular
interest because, in addition to having a relatively high
whole rock delta-D, there is evidence that it contains
several distinct D carriers.