Citation

Hooper DM, Mattioli GS. Nat. Hazards 2001; 23(1): 65-86.

Copyright

(Copyright © 2001, Holtzbrinck Springer Nature Publishing Group)

DOI

unavailable

PMID

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Abstract

Volcanic activity commenced 18 July 1995 at Soufriere Hills volcano and has led to the creation of a new lava dome, which has repeatedly collapsed between 1996 and 1999 resulting in highly mobile pyroclastic flows. The majority of associated pyroclastic flow phenomena are consistent with initiation by gravitational collapse as blocks fall from oversteepened flanks of the new dome. If gravity controls the energy transfer of such collapses, then areas likely to be affected can be predicted on the basis of topography. We focus on 'dense' flows initiated by non-explosive, gravitational collapse ('Merapi-type' pyroclastic flows) and employ a graphical computer model (Flow3D) written to simulate this type of volcanic flow. The program constructs a digital terrain model based upon a 3D network of (x, y, z) triplets, which serves as the basis for the numerical computations. A synthetic dome was added to the topographic model to improve the accuracy of the simulations. After estimating the small number of key adjustable parameters, simulated flow pathways, runout distances, and velocities closely approximated observed Merapi-type pyroclastic flows on Montserrat. These simulations demonstrate the validity of a simple kinematic method to model dense pyroclastic flow phenomena. While the simulations presented here do not elucidate additional physics of pyroclastic flow phenomena, this type of modeling can be completed easily and without extensive a priori knowledge of volcano-specific parameters other than topography. Accordingly, it may serve as a rapid and inexpensive first-order approach for initial hazard assessment.

Language: en