[1] Plate tectonics constitutes our primary framework for understanding how the Earth works over geological timescales. High-resolution mapping of relative plate motions based on marine geophysical data has followed the discovery of geomagnetic reversals, mid-ocean ridges, transform faults, and seafloor spreading, cementing the plate tectonic paradigm. However, so-called ‘‘absolute plate motion...

We consider a one-dimensional two-phase Stefan problem, modeling a layer of solid material floating on liquid. The model includes internal heat sources, variable total mass (resulting e.g. from sedimentation or erosion), and a pressuredependent melting point. The problem is reduced to a set of nonlinear integral equations, which provides the basis for an existence and uniqueness proof and a new...

Abstract. After accretion and formation, terrestrial planets go through at least one magma ocean episode. As the crystallises, it creates first layer of solid rocky mantle. Two different scenarios crystallisation involve that mantle either (1) appears core–mantle boundary grows upwards or (2) mid-mantle depth in both directions. Regardless freezing scenario, composition liquid reservoirs contin...

The boundary between the rocky mantle and iron core, almost 2900 km below the surface, is physically the most significant in the Earth's interior. It may be the terminus for subducted surface material, the source of mantle plumes and a control on the Earth's magnetic field. Its properties also have profound significance for the thermochemical and dynamic evolution of the solid Earth. Evidence f...

Starting with Kelvin there have been many controversies and paradoxes associated with the evolution of the Earth. These are not faith-based controversies, in the ordinary sense; they are based on calculations and assumptions which are a form of faith . Present-day heat flow is determined by the amount and distribution of radioactive elements, their secular decline with time, the delay between h...

Paleomagnetic data provide one of the few probes available to interrogate early evolution of the core. Here we apply this probe by examining the latitudinal dependence of paleosecular variation (PSV) data derived from high-quality paleomagnetic data collected from Proterozoic and Neoarchean rocks. These data define a Neoarchean geomagnetic field that was more dipolar than that during Proterozoi...