Input file - Geodels/eSCAPE GitHub Wiki

About | Input file | Dependency | Docker | Local Installation | HPC Installation | Tutorials

← Previous topic: About | Next topic: Dependency →

Input files for eSCAPE are based on YAML syntax.

A typical file will look like this:

name: Description of the what is going to be done in this simulation...

domain:
    filename: ['data/inputfileparameters.vtk','Z']
    flowdir: 5
    bc: 'slope'
    sphere: 0

time:
    start: 0.
    end: 1000000.
    tout: 1000.
    dt: 100.

sea:
    position: 0.
    curve: 'data/sealevel.csv'

climate:
    - start: 0.
      uniform: 1.0
    - start: 500000.
      map: ['data/inputfileparameters.vtk','R']
    - start: 500000.
      uniform: 2.0

tectonic:
    - start: 0.
      mapZ: ['data/inputfileparameters.vtk','T1']
    - start: 100000.
      uniform: 0.
    - start: 50000.
      mapZ: ['data/inputfileparameters.vtk','T2']

sp_br:
    Kbr: 1.e-5

sp_dep:
    Ff: 0.3

diffusion:
    hillslopeK: 1.e-6
    sedimentK: 5.e6

output:
    dir: 'outputDir'
    makedir: False

The YAML structure is shown through indentation (one or more spaces) and sequence items are denoted by a dash. At the moment the following component are available:

• domain: definition of the unstructured grid containing the vtk grid filename and the associated field (here called Z) as well as the flow direction method to be used flowdir that takes an integer value between 1 (for SFD) and 12 (for Dinf) and the boundary conditions (bc: 'flat', 'fixed' or 'slope')
• time: the simulation time parameters defined by start, end, tout (the output interval) and dt (the internal time-step).

Follows the optional forcing conditions:

• sea: the sea-level declaration with the relative sea-level position (m) and the sea-level curve which is a file containing 2 columns (time and sea-level position).
• climatic & tectonic have the same structure with a sequence of events defined by a starting time (start) and either a constant value (uniform) or a map.

Then the parameters for the surface processes to simulate:

• sp_br: for the stream power law with a unique parameter Kbr representing the erodibility coefficient which is scale-dependent and its value depend on lithology and mean precipitation rate, channel width, flood frequency, channel hydraulics. It is worth noting that the coefficient m and n are fixed in this version and take the value 0.5 & 1 respectively.
• diffusion: hillslope and marine diffusion coefficients. hillslopeK sets the simple creep transport law which states that transport rate depends linearly on topographic gradient. The marine sediment are transported based on a diffusion coefficient sedimentK.

Finally, you will need to specify the output folder:

• output: with dir the directory name and the option makedir that gives the possible to delete any existing output folder with the same name (if set to False) or to create a new folder with the give dir name plus a number at the end (e.g. outputDir_1 if set to True)

The tutorials proposed in the eSCAPE-demo repository present several examples to create the required vtk input files (used in the input files for the domain, the climate, and the uplift) for running eSCAPE.

These input files are defined on an irregular triangular grid (TIN) which is created using either the pyGmsh or stripy libraries (both install on the Docker container).

In case of spatial change in forcing conditions, the user needs to specify (using the map element) for each vertices of the TIN, a series of fields for each forcing (tectonic displacements and precipitation) at chosen time intervals.

In cases where the forcing conditions are uniform over the entire domain one can chose to define its values in the YAML input file directly using the uniform element.

Sea level position can be set at a given relative position using the position element or using a curve which is a file containing 2 columns (time and sea-level position). In this later case, sea level position at any timestep is obtained by linear interpolation between closest sea level times.

Model-domain edge boundary conditions are set using the bc element in the YAML input file and the following options are available:

• flat: edges elevations are set to the elevations of the closest non-edge vertices
• fixed: edges elevations remain at the same position during the model run
• slope: edges elevations are defined based on the closest non-edge vertices average slope

The model outputs are located in the output folder (dir element) and consist of a time series file named eSCAPE.xdmf and 2 other folders (h5 and xmf). The XDMF file is the main entry point for visualising the output and should be sufficient for most users.

The file can be opened with the Paraview software.

A video is provided in the eSCAPE-demo repository test/data folder and shows how to visualise eSCAPE output.

As shown in the video, after loading the file, we perform 2 operations:

• first we use the wrap by scalar filter to create a 2D representation of the surface
• then we define a contour line corresponding to the sea-level position