A relation between lava discharge rate, thermal insulation, and flow area set using lidar data

A simple linear relation can be used to link time averaged discharge rate (TADR) and lava flow area (A). The relation applies to given insulation conditions, as described by the characteristic flow surface temperature (Te), and will vary from case-to-case depending on rheological and topographic influences on flow spreading. Most flows have insulation conditions that change through time, modifying the relationship between TADR and area as insulation conditions evolve. Using lidar data we can define TADR, the flow area that the discharge feeds and Te, allowing generation of a case-specific relation to convert satellite-data-derived flow areas to TADR. For Etna’s 2006 lava flow field we obtain a relation whereby TADR = 5.6 x 10^6 A for well insulated conditions (Te=100°C) and TADR = 1.5 x 10^4 A for poorly insulated conditions (Te = 600°C).