Monday, June 21, 2010

Isotope fractionation during impacts (All rights reserved)


Evaporation–condensation, a significant process, happened during impact events (Melosh 1989). Of special interest, this process can lead to significant isotope fractionations. The nature of the isotope fractionations is the energy for the bonds formed by the light isotope is less than bonds involving the heavy isotope (Hoefs 2009). During evaporation, the solid or liquid is enriched in the heavy isotopes relative to the gas (Fig.1A Richter and Dauphas 2009). During condensation, the solid or liquid is enriched in the light isotopes (Fig.1B Richter 2004). Earlier condensed material is enriched in lighter isotope whereas samples with the heavier isotope (especially positive values) could be the later condensed material or the residue of vaporization. This idea is being ubdated, all the references will be added soon.