Experiment 8: Mantle Convection & Plate Tectonics
Despite being solid silicate rock, the Earth's mantle behaves as a highly viscous fluid over millions of years, convecting heat away from the hot core. This convective circulation is the engine driving plate tectonics. Use this simulation to examine convection onset, mantle plumes, slab subduction, and heat flow.
Rheology Settings
Mantle Temperature & Velocity FieldRa = 0.00e+0
Mid-Depth Temperature
Tracks mixing efficiency. Steady at 0.50 for conduction; oscillates for convection.
Thermal Convection Physics
Critical Rayleigh Number
In flat layer models, convection occurs only when the buoyancy forces overcome viscous resistance and thermal diffusion. This onset is marked by the critical Rayleigh number, which is typically Ra_crit ≈ 1000. For Ra < 1000, heat transport is completely conductive and the temperature profile remains linear.
Solid State Creep
Although the Earth's mantle is composed of solid silicate minerals, high temperatures and confining pressures allow the rock to deform slowly by solid-state creep. Over geological timescales (tens of millions of years), this slow movement allows the mantle to flow and circulate, transferring core heat to the surface.