Simultaneous generation of hotspots and superswells by convection in a heterogeneous planetary mantle. The influence of interior mantle temperature on the structure of plumes: Heads for Venus, tails for Earth. Numerical investigation of 2D convection with extremely large viscosity variations. Heat transport by variable viscosity convection and implications for the Earth's thermal evolution. A matrix-dependent transfer multigrid method for strongly variable viscosity infinite Prandtl number thermal convection. Mantle convection modeling on parallel virtual machines. Lunar rotational dissipation in solid body and molten core. On the thermal evolution of the Earth's core. Thermal histories of the core and mantle. Magnetism and thermal evolution of the terrestrial planets. The ‘Procellarum KREEP Terrane’: Implications for mare volcanism and lunar evolution. A dynamic origin for the global asymmetry of lunar mare basalts. Experiments and their application to Earth's core and mantle. Mixing and compositional stratification produced by natural convection. The magma ocean concept and lunar evolution. A model for the thermal and chemical evolution of the Moon's interior: Implications for the onset of mare volcanism. Three dimensional treatment of convective flow in the Earth's mantle. Thermal history of the Moon: Implications for an early core dynamo and post-accretional magmatism. Magnetism of the Moon-A lunar core dynamo or impact magnetization? Surv. A review of lunar paleointensity data and implications for the origin of lunar magnetism. The removal of the thermal blanket, proposed to explain the eruption of thorium- and titanium-rich lunar mare basalts 7, plausibly results in a core heat flux sufficient to power a short-lived lunar dynamo.Ĭisowski, S.
Subsequent radioactive heating progressively increases the buoyancy of the thermal blanket, ultimately causing it to rise back into the mantle. Using a three-dimensional spherical convection model 6, we show that a dense layer, enriched in radioactive elements (a ‘thermal blanket’), at the base of the lunar mantle can initially prevent core cooling, thereby inhibiting core convection and magnetic field generation.
Here we show that a transient increase in core heat flux after an overturn of an initially stratified lunar mantle might explain the existence and timing of an early lunar dynamo. But the presence of a lunar dynamo during this time period is difficult to explain 1, 2, 3, 4, because thermal evolution models for the Moon 5 yield insufficient core heat flux to power a dynamo after ∼4.2 Gyr ago. Although the Moon currently has no internally generated magnetic field, palaeomagnetic data, combined with radiometric ages of Apollo samples, provide evidence for such a magnetic field from ∼3.9 to 3.6 billion years (Gyr) ago 1, possibly owing to an ancient lunar dynamo 1, 2.
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