Lava flow in a channel with a bifurcation

Etna poses risks to inhabited areas with its frequent effusive eruptions. D uring the 1989 and.1991 eruptions the Italian Department of Civil Protectio n diverted the lava from its natural path into an artificial channel, reduc ing the risk of flava inundation. The intervention resulted in the creation of a bifurcation between the natural and the artificial channels. In this paper magma dynamics in the bifurcation is investigated by solving the equa tions of mass and momentum balance with a simplified two-dimensional geomet ry, describing magma as an homogeneous, isothermal incompressible fluid wit h Newtonian rheology. Results show the important role played by the slope o f the artificial channel and the effect of the width of the artificial mout h on the efficiency of the diversion. (C) 1999 Elsevier Science Ltd. All ri ghts reserved.