The thermal model proposed by Crisp and Baloga (1990) for active lava flows considers thermal flux as a function of the fractional area of two thermally distinct radiant surfaces. In this model. the larger surface area corresponds to the cooler crust of the flow and the other. much smaller to fractures in the crust. https://www.diegojavierfares.com/flash-offer-Finney-Two-Handle-High-Arc-Bathroom-Faucet-p8561-super-offer/