Thermal evolution of Mercury: Effects of volcanic heat-piping

Abstract

A 1D thermal evolution model of Mercury is presented. It accounts for stagnant lid convection, mantle differentiation and inner core growth. Early MESSENGER results indicate that - contrary to prior conclusions drawn from Mariner 10 imagery - volcanism has indeed played a significant role in Mercury's past. To study the effects of mantle heat bypassing the stagnant lid by means of volcanic heat-piping, contrasting end-member models are considered. Results show how break-down of mantle convection and onset of inner core growth are influenced by the mode of heat removal. Structural models of present day Mercury are presented. Their dependence on the core sulphur contents predominates that on the choice of mantle heat removal. However, the latter clearly controls the timing of thermal history events. Copyright 2009 by the American Geophysical Union.