Mean value is 65 mW/m2 over continental crust and 101 mW/m2 over oceanic crust.
0.9 and 105.4 mW/m2.[1]
See also
Physics / Thermodynamics / Heat Transfer / Heat flow / Heat Flux
Reference
Davies, J. H., & Davies, D. R. (2010). Earth's surface heat flux. Solid Earth, 1(1), 5–24.