Thermal history of a Mercury with radioactive elements concentrated in a crust

Abstract

We examine the effect of mantle heat source distribution on the thermal evolution of Mercury. The radioactive elements, which are incompatible elements, are likely to be enriched in the crust. While Earth's crustal material partly returns to the mantle by the plate motion, Mercury's crustal elements are likely to be retained because of the lack of plate motion. This implies that Mercury's mantle has less heat sources and secular cooling may be more efficient. We calculate Mercury's thermalhistory by using mixing length theory and compare the highlydifferentiated mantle model with the homogeneous mantle model.