Hazard estimation of the possible pyroclastic flow disasters using numerical simulation related to the 1994 activity at Merapi Volcano

A pyroclastic how, generated at Merapi Volcano on 22 November 1994, flowed down the Boyong and Krasak Rivers, which are located on the south slope of the volcano. The flow greatly damaged the Kaliurang and Turgo areas. Follow ing this event, it was feared that another pyroclastic how might cause addi tional damage to these areas because the lava dome continued to grow increa singly unstable. There was also fear that other pyroclastic flows would aff ect other areas on the flanks of Merapi Volcano. Using a 2-dimensional nume rical simulation, the authors estimated the areas potentially affected by f urther pyroclastic flow activity. Numerical simulation has proved useful in determining potential areas of inundation on the south flank of Merapi Vol cano. Although the simulations are sensitive to many input parameters, we h ave determined that the strongest influence comes from initial flow directi on and topography. (C) 2000 Elsevier Science B.V. All rights reserved.