Geocheminar spring-2016

First Measurements of the Thermal Properties of Ordinary Chondrites at High Temperature

Here we report measurements of the thermal properties (heat capacity, thermal conductivity, and thermal diffusivity) of ordinary chondrite samples as a function of temperature using the laser flash method. These measurements have been carried out for the first time at temperatures above 500 K, including values near the peak temperatures expected during thermal metamorphism of the meteorite parent bodies. Values are generally in agreement with those reported by previous authors. Our first results suggest that at high temperatures, thermal diffusivity is more affected by metal content and less affected by porosity than at low temperatures. We use fits derived to our measurements to model the thermal evolution of meteorite parent bodies and compare these results to those that are collected using estimates for the thermal properties commonly found in the literature. We note the strong effect that even fairly subtle alterations in the thermal properties of the material have on the evolution of the model parent bodies, and look ahead to upcoming results which will allow us to construct more representative models of parent-body alteration.