The half-space cooling solution for oceanic lithosphere
PHYSICS · Multi-part · Fermi University Physics · Thermal, Statistical & Complex Systems · Earth, Climate & Energy Physics · The solid Earth: structure, fields and thermal history
The Solid Earth, Ch Dating, heat flow and the thermal history of the Earth
Problem
The half-space cooling solution for oceanic lithosphere, with T0=0∘C at the surface, is T(z,t)=T0+(Tm−T0)erf(η) with similarity variable η=z/(2κt).
((a)) Derive a general expression for the depth zc(t) of an isotherm of temperature Tc, in terms of Tc, Tm−T0, κ, t and the inverse error function.
((b)) Take Tm−T0=1345K, an isotherm Tc=700∘C, and κ=10−6m2s−1. Using the table value erf(0.5)=0.5205, find the depth of this isotherm at an age t=30Myr.