Relationships Among Regolith Thermal Conductivities and Seismic Velocities: Application to InSight Studies

Kurzfassung

Studies of the thermal and seismic properties of planetary regoliths are complex because of uncertainties and variability in composition, particle and pore geometrical shape, size distribution, and three-dimensional physical connectivity. Therefore, correlations among physical properties that relate to geophysical parameters that may be measured directly or indirectly are potentially useful for studying regoliths. Studies of relationships among seismic velocities and thermal conductivities of terrestrial rocks and minerals indicate general positive correlations, often with non-Gaussian scatters in the correlations that may result in part from heterogeneity in samples used for thermal conductivity determinations. Plots of laboratory data for seismic velocities versus thermal conductivity under ambient conditions for minerals and rocks are shown in Figs. 1 and 2, respectively. These data indicate linear relationships within the limitations of the data chosen. In this contribution we have compiled and collated thermal and seismic velocity data relevant to the Mars regolith and present a preliminary relationship for the regolith at the InSight landing site.