Supporting Information for

Geophysical Research Letters

A unifying model for pyroclastic surge genesis and pyroclastic flow fluidization

Karim Kelfoun, Valentin Gueugneau

Modelling of block trajectories and impacts

A simplified and annotated version of the code is available here as well as the synthetic surface used for the code validation:

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The code runs in Matlab and Octave.

Execute main.m to compute the trajectory. You can modify the initial conditions and the block properties to compute other trajectories.

Description of the files:
main.m - main program which computes the displacements in the air and calls the other functions
bounce3D.m - computes the bounce
slide3D.m - computes the sliding
slope.mat - synthetic topography used for the example

Numerical simulations of fluidized flows

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VolcFlow runs in Matlab (p-code file).

Select the VolcFlow folder
Write VolcFlowFluidization in the command window.
Select either input_file_100_20_01_noexpansion.m or input_file_100_20_01_expansion.m
click on the ok button.

Description of the files:
Two input files are provided:
input_file_100_20_01_noexpansion.m - input file of VolcFlow (used for Fig. 4) that simulates non-expanded flow and accepts overpressure
input_file_100_20_01_expansion.m - input file of VolcFlow that simulates a flow that can expand with a maximum ratio hexpand/hcompacted equal to 1.5.

Two source conditions are provided:
source_novelocity.m - source conditions of the flow: no initial velocity of the blocks and momentum calculation related to this condition.
source_free.m - source conditions of the flow: the initial velocity is equal to the flow velocity.

repr_PDCs.m - a script that can be used to visualize of the flow and the topography
colorscale.tif - tif image that is used to define the colorscale of repr_Merapi.m
topo.mat - digital topography of Merapi volcano