5.) given a mean radioactive heat production in continental rocks of a = 2.4 x 10-13 cal/(cm3 -sec), initial conditions on to and dt/dz from surface temperature and heat flow measurements, use the equation developed in problem 3 for the continental geotherm to estimate at what depth the melting temperature of mantle rocks would be reached. ( assume a heat flow of 1.5 hfu, thermal conductivity from assigned readings, a surface temperature to = 20° c, and a melting temperature of 1200° c. remember to convert to common units. show all steps). this calculation as noted in garland's book was used by strutt (lord rayleigh) to conclude that radioactive elements must be concentrated in the earth's continental crust.