Are terrestrial plumes from motionless plates analogues to Martian plumes feeding the giant shield volcanoes?

Abstract

AbstractOn Earth, most tectonic plates are regenerated and recycled through convection. However, the Nubian and Antarctic plates could be considered as poorly mobile surfaces of various thicknesses that are acting as conductive lids on top of Earth's deeper convective system. Here, volcanoes do not show any linear age progression, at least not for the last 30 myr, but constitute the sites of persistent, focused, long-term magmatic activity rather than a chain of volcanoes, as observed in fast-moving plate plume environments. The melt products vertically accrete into huge accumulations. The residual depleted roots left behind by melting processes cannot be dragged away from the melting loci underlying the volcanoes, which may contribute to producing an unusually shallow depth of oceanic swells. The persistence of a stationary thick depleted lid slows down the efficiency of melting processes at shallow depths. Numerous characteristics of these volcanoes located on motionless plates may be shared by those of the giant volcanoes of the Tharsis province, as Mars is a one-plate planet. The aim of this chapter is to undertake a first inventory of these common features, in order to improve our knowledge of the construction processes of Martian volcanoes.