Parameters files

There are different types of parameters files for the source areas identification and for the propagation assessment. These are xml files that can be edited using a text editor. New files can also be added to introduce new parameters.

These parameters files can be found in the folders parameters/sources or parameters/propagation. You have to identify the files for which the beginning of their name is bound to the desired data or algorithms.

Source areas assessment

The given datasets used for the source areas assessment are of two types: classes / indices (e.g. geology) or continuous data (e.g. flow accumulation). The parameters files (in the directory parameters/sources) differ according to the nature of the dataset.

Input data as classes

Datasets that represent classes or indices are for example geology or landuse layers. The grids contain codes corresponding to a certain class. The parameters file allows to choose a threshold slope above which the cells are considered as favorable for initiation, for every class. Any class can also be excluded or ignored (by setting the value to 1).

<?xml version="1.0"?>

<main version="0.6.0">

<!--CAUTION: Numbers only.

No accent (UTF-8 code OK)!

Exclude & ignore are boolean choices.

Slopes in degrees-->

<!--Geology criteria set for Pakistan-->

<!--list of criteria-->

<criterion description="Salkhala Formation" exclude="0" ignore="0">

<gridcode>1</gridcode>

<threshold_slope unit="degrees">15</threshold_slope>

</criterion>

<criterion description="Mansehra Orthogneiss" exclude="0" ignore="0">

<gridcode>2</gridcode>

<threshold_slope unit="degrees">15</threshold_slope>

</criterion>

<criterion description="Tanawal Formation" exclude="0" ignore="0">

<gridcode>3</gridcode>

<threshold_slope unit="degrees">15</threshold_slope>

</criterion>

<criterion description="Panjal Volcanics" exclude="0" ignore="0">

<gridcode>4</gridcode>

<threshold_slope unit="degrees">15</threshold_slope>

</criterion>

<criterion description="Stream Channel Deposits" exclude="0" ignore="0">

<gridcode>5</gridcode>

<threshold_slope unit="degrees">15</threshold_slope>

</criterion>

<criterion description="Surficial Deposit" exclude="0" ignore="0">

<gridcode>6</gridcode>

<threshold_slope unit="degrees">15</threshold_slope>

</criterion>

<criterion description="Flood Plain Deposit" exclude="0" ignore="0">

<gridcode>7</gridcode>

<threshold_slope unit="degrees">15</threshold_slope>

</criterion>

<criterion description="Panjal Metasediments" exclude="0" ignore="0">

<gridcode>8</gridcode>

<threshold_slope unit="degrees">15</threshold_slope>

</criterion>

<criterion description="Terrace Deposit" exclude="0" ignore="0">

<gridcode>9</gridcode>

<threshold_slope unit="degrees">15</threshold_slope>

</criterion>

<criterion description="Patala Formation and Lockhart Limestone" exclude="0" ignore="0">

<gridcode>10</gridcode>

<threshold_slope unit="degrees">15</threshold_slope>

</criterion>

...

</main>

Input data as continuous information

When datasets represent a continuous information, such as flow accumulation or curvature, the criteria need to be defined for a range of values. The parameters file allows to choose a threshold slope above which the cells are considered as favorable for initiation, for every range. Any range can also be excluded or ignored (by setting the value to 1).

<?xml version="1.0"?>

<main version="0.6.0">

<!--CAUTION: Numbers only.

No accent (UTF-8 code OK)!

Exclude & ignore are boolean choices.

Slopes in degrees

grid_min_val is ">=" & grid_max_val is "<" -->

<!--(Flow accumulation - slope) relationship for extreme events on a grid with 20m cells-->

<!--list of criteria-->

<criterion description="1-25 cells" exclude="1" ignore="0">

<grid_min_val>1</grid_min_val>

<grid_max_val>25</grid_max_val> <!--in terms of cells number-->

<threshold_slope unit="degrees">0</threshold_slope>

</criterion>

<criterion description="25-63 cells" exclude="0" ignore="0">

<grid_min_val>25</grid_min_val>

<grid_max_val>63</grid_max_val>

<threshold_slope unit="degrees">31</threshold_slope>

</criterion>

<criterion description="63-125 cells" exclude="0" ignore="0">

<grid_min_val>63</grid_min_val>

<grid_max_val>125</grid_max_val>

<threshold_slope unit="degrees">28.4</threshold_slope>

</criterion>

<criterion description="125-188 cells" exclude="0" ignore="0">

<grid_min_val>125</grid_min_val>

<grid_max_val>188</grid_max_val>

<threshold_slope unit="degrees">26.1</threshold_slope>

</criterion>

<criterion description="188-250 cells" exclude="0" ignore="0">

<grid_min_val>188</grid_min_val>

<grid_max_val>250</grid_max_val>

<threshold_slope unit="degrees">24.7</threshold_slope>

</criterion>

...

</main>

Propagation assessment

Most algorithms for the propagation assessment need specific parameters. These are given by means of parameters files (in the directory parameters/propagation) that can be edited. Here is an example of the parameters required for the two parameters friction model from Perla (1980). This kind of files can be copied and edited to add new options of parameters.

<?xml version="1.0"?>

<main version="0.6.0">

<!--CAUTION: Numbers only.

No accent (UTF-8 code OK)!-->

<!--Algorithm form the 2 parameters friction model-->

<!--list of parameters-->

<parameter name="mass2drag" description="mass-to-drag ratio (m)">

<value>1000</value> <!--for avalanches, from Perla et al, 1980-->

</parameter>

<parameter name="mu" description="friction coefficient (-)">

<value>0.3</value> <!--for avalanches, from Perla et al, 1980-->

</parameter>

</main>