Inputs

Input parameter values are taken from: (a) parameters file 'project.PRM', (b) command line options, (c) other input files named 'project.*' (with an uppercase extension), and (d) from the 'project.all' file if -F option is used. (b) values override (a); (c) overrides (a) and (b); (d) overrides (a) and (c). Default units are I.S. All the following input files accept comment lines to be inserted everywhere. These lines will simply be ignored if a parameter name and a numerical value cannot be read at the beginning. All input files are read in the begining of the execution, at the initial time, except for *.UNIT (which are read at their respective specified times) and for *.NDEF (read at every time step dt_eros).

'project.PRM' Parameters file: This file is compulsory unless using the -Q option. The parameter values defined in it can be also changed with the command line options listed above. 'tisc/doc/template.PRM' file is an explained example containing the default parameter values. The internal use of each parameter is also somewhat explained in the incude file 'tisc.h'. --xmin, xmax, ymin, ymax give the coordinates of the center of the boundary cells or pixels (i.e., the location of their associated nodes). The conceptual limit of the model is at xmin-dx/2, ymax+dx/2, ... For example, if the resolution of a model is needed to be reduced to dx/2,dy/2 keeping the same domain parameters, then the new Nx,Ny should not be Nx2,Ny2, but (Nx-1)*2+1,(Ny-1)*2+1. --If (switch_topoest != 0) then the load will rest at zero level and plate subsidence will be filled with 'densinfill' material. Do not use it with erosion model.

'projectN.UNIT' File modifying the geometry/architecture of the model (i.e, introducing new bodies, moving blocks, or faults). 'N' is the number of this load; first load file should be: 'project1.UNIT'; 'doc/template.UNIT' file is an explained example. Or type 'tisc -hu' to get that file in the screen. TISC deformation consists of moving predefined blocks of prescribed velocity and geometry by an entire number of cells at each time step. The minimum shift is either 0 or 1 cells. If your time step dt is 0.5 Myr, velocity is 5 km/Myr and cell size is 10 km, the block will move only once every 4 time steps. So, depending on the grid cell size, the motion will become more or less abrupt. See about 'Interpolation' at the end of this section.

'project.EET' Equivalent Elastic Thickness file (optional, if not present EET will be taken from the *.PRM file). Note that abrupt EET lateral changes can lead to instabilities in the calculation of flexural deflection. The file format is: [z_default --] #Default value of the elastic thickness. [mode_interp -] #See explanation in doc/template.UNIT. x1 y1 thickness1 x2 y2 thickness2 x3 y3 thickness3 ... Or: [mode_interp 4] thickness1 x1 y1 x2 y2 x3 y3 thickness2 x2 y2 x1 y1 ...

'project.PRFL' This file (optional) defines a x-y polygon corresponding to the cross section that will be written in a '*.pfl' file. Default is no cross section. The file format is:

x1  y1
x2  y2
x3  y3
...

'project.ZINI' Initial topography (optional). Similar format to 'project.EET'.

'project.WINI' Initial deflection file (optional): Similar format to 'project.EET'. Positive deflection downwards.

'project.RAIN' Runoff distribution (optional): Similar format to 'project.EET'. Units: mm/a. Negative values and undefined cells are interpreted as no-data and substituted by the automatic calculation from the parameters in *.PRM. The values in *.RAIN are kept constant through the entire model evolution.

'project.NDEF' Allows to change properties of specific nodes: Format:

x	y	param 	value
...	...     ...	...

the closest node to x,y will be changed: 'param' determines what
parameter is changed at that node:   1: to add water discharge at x,y
(m3/s, max. is Amazon at 120e3).  2: to add sediment discharge (kg/s,
max. is Ganges at 52e3). This file, in contrast  to all others, is read
not once at startup but once for every surface  process iteration.

'project.SLV' Evolution of the sea level and the level separating erosion and sedimentation levels (optional): Format:

time1	s_level1	[eroslevel1]
time2	s_level2
time3	s_level3	[eroslevel2]
...	...     	[...]

'project.REC' Horizon recording times file (optional, defaults to dt_record parameter, see *.PRM file): Format:

time1
time2
time3
...

'project.RIV' Initial river paths that must be respected by the initial topography. When introducing a Digital Elevation Model through the *.ZINI file, the grid may not respect the path of the rivers because of its limited resolution, which generates unrealistic barriers. This file must be introduced in order to allow the program to modify the topographic grid and fit it to the drainage network. Introduce river in x-y format starting from the highest point. Different segments can be separated by lines starting with '>'.

'projectN.VISC' Only required if a thin sheet unit has been defined. Contains the viscosity x,y distribution for unit 'N', but only its thermal component (~ .1e7). The total viscosity will be calculated as viscosity[Pa*s] = viscTer/str.rate. Format is equivalent to file 'project.EET'.

'project.TSBC' Only required if defining a thin sheet unit. Boundary conditions of the thin sheet velocity or stress field for the units is defined to undergo a thin-sheet-like deformation. Format is: N'type' x1 vx1 vy1 x2 vx2 vy2 x3 vx3 vy3 S'type' ... E'type' y1 vx1 vy1 y2 vx2 vy2 y3 vx3 vy3 W'type' ... N, S, E, and W indicate the boundary. vx,vy depend on 'type': type=1 means vx,vy are the components of the velocity [km/My] at the boundary; type=12 fixes stress TAUxx and TAUxy; type=13 fixes TAUxx,TAUyy; type=23 fixes TAUxy,TAUyy; type=4 means free slip (nomal_vel=0 and TAUxy=0).

'project.CMP' This file defines x-y polygons (in km) separated with a '>', used only to be plotted in the postscript image, called from graphic script like script/tao.gmt.job, just for comparison with model results.

'project.INT' This file defines a x-y polygon (in km) of interest where certain statistics should be performed during the execution of graphic scripts. Used only to be plotted in the postscript image, called from graphic script like script/tao.gmt.job, just for comparison with model results.No effect on model results.

Interpolation: Most TISC input files define 3D surfaces or 2D planform distributions of a variable. To facilitate this, TISC accepts different ways of interpolation between given points. For example, interpolation mode 0 indicates that Nx*Ny values of <x,y,variable> will be read from the file (useful to pass a surface generated externally with SURFER, for example). Read the specifications for each mode in tisc/doc/template.UNIT. If the mode_interp is set to 4 or 7 then x-y polygons are read with an associated z-value. In this case the format is:

mode_interp  4
z_value_pol_1	[n|c]
x_pol1_1      y_pol1_1
x_pol1_2      y_pol1_2
x_pol1_3      y_pol1_3
...
z_value_pol_2	[n|c]
x_pol2_1      y_pol2_1
x_pol2_2      y_pol2_2
x_pol2_3      y_pol2_3
...

For mode_interp=4 or 7, if 'c' is specified for a polygon, the z value inside that polygon will be constant. If 'n' is specified (default), the z value interpolated for all nodes falling inside that polygon but outside the next polygon will vary linearly with the distance to both polygons. So, tricky as it seems, the order of the polygons matters!