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Continental Geotherms |
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This relationship gives the distribution through depth of temperature in a layer with homogeneous radiogenic production A, conductivity k, with a surface temperature of To and a surface heat flow of Qo. |
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| The continental lithosphere consists in two layers with contrasted thermal properties. In particular the radiogenic heat production in the mantle is negligible compared to that of the crust. The geotherm of continental lithoaphere is therefore best described by two relationships, one for the crust (equation above), one for the lithospheric mantle. |
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If the production of radiogenic heat is zero in the mantle then we get: |
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Integrating twice we get: |
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With the two following boundary conditions: T=Tc at z=zc=Moho, and Q=-Qm (the basal heat flow), we get: |
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and... |
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The geotherm in the lithospheric mantle is therefore: |
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