Thermal Evolution of the Impact-Induced Cryomagma Chamber Beneath Occator Crater on Ceres

The faculae in Occator Crater on dwarf planet Ceres are an accumulation of salts that have been interpreted as cryovolcanic products. Current age estimates from crater counting suggest a maximum 18-Ma difference between the crater forming impact and the formation of Cerealia Facula, the central and most recent region in the crater. Here we model the thermal evolution of the potential impact-induced cryomagma chamber beneath Occator Crater and show that it cools in less than 12 Ma. To reach cooling times of 18 Ma requires initial melt volumes exceeding 11,000 km(3). However, simulations suggest that smaller initial cryomagma chambers may lead to partial melting of the lower crust. This may allow recharge of the magma chamber by deep brines located in the porous upper mantle of Ceres and may extend the longevity of cryovolcanic activity.