THE 1992 ETNA LAVA FLOW IMAGED BY LANDSAT TM

As we write (May 1992) a lava flow that began at a fissure high on the southeast flank of Mount Etna, Sicily, on 14 December 1991 (Smithsonian Institution, 1991, 1992) has been threatening the town of ZalTerana for several weeks and considerable media attention has been given to attempts to divert the flow, or to breach its levees, so that the lava spreads laterally rather than continuing downslope into the town. In order fully to understand the behaviour of an active lava flow it is important to measure as many relevant properties as possible. Among these are the volumetric rate of effusion, the steepness of the slope and other terrain properties, the planimetric form of the flow, the rate of advance of the head of the flow, and the temperature and viscosity of the lava (Walker 1973, Crisp and Baloga 1990). Only when at least several of these parameters are well-constrained can realistic models be created that are capable of predicting the course of the flow. © 1992 Taylor & Francis Group, LLC.