Derrick Hasterok1, Matthew Gard1, Grant Cox1, Martin Hand1
1University Of Adelaide, Adelaide, Australia
Radiogenic heat production is one of the greatest uncertainties in thermal models of the lithosphere. The difficulty in sensing radiogenic heat production using remote sensing techniques has been an impediment to developing accurate thermal models of the continental lithosphere. Most studies simply assume heat production values based on an average continental lithospheric composition, but heat production varies considerably from region to region. In this study, we present heat production estimates from >200,000 whole-rock analyses distributed globally. We find that patterns of heat production fundamentally differ between igneous and sedimentary rocks as a function of major element chemistry and physical properties. For igneous samples, heat production can be correlated to seismic velocity and density, which can be used as a proxy for estimating heat production with depth. Systematic variations in heat production also exist in space and with crystallization age that must also be accounted for when developing crustal models. We demonstrate how this method can be used to estimate the heat production of the Australian lithosphere, which produces results similar to independent estimates of heat production derived from thermal isostatic methods. From this dataset, it is possible to develop a set of predictors for heat production of Antarctic terranes both laterally and vertically.