TOBIA
- Author: A. Günther (c) 2012
- Menu: Terrain Analysis | Slope Stability
Description
This tool computes both a continuous and a categorical TOBIA (Topography Bedding Intersection Angle) Index according to Meentemeyer & Moody (2000) For computation, a slope and a aspect raster (both in radians) determining slope face orientations are required. The categorical TOBIA classifies the alignment of a geological structure to Topography into seven classes:
0) Underdip slope
1) Dip slope
2) Overdip slope
3) Steepened escarpmemt
4) Normal escarpment
5) Subdued escarpment
6) Orthoclinal slope
The continuous TOBIA index ranges from -1 to 1 (parallel orientation)
The structure TOBIA should be calculated with can be set either distributed (through dip direction and dip grids, in degrees!), or globally using integers (dip and dip direction, in degrees!). The tool creates a TOBIA class integer grid, and (optionally) a continuous TOBIA index grid.
Reference: Meentemeyer R. K., Moody A. (2000). Automated mapping of conformity between topographic and geological surfaces. Computers & Geosciences, 26, 815 - 829.
Parameters
| | Name | Type | Identifier | Description | Constraints |
|---|
| Input | Slope grid (rad) | grid, input | A | A slope angle grid (in radians) | - |
| Aspect grid (rad) | grid, input | B | A aspect angle grid (in radians) | - |
| Dip grid (degrees) | grid, input, optional | C | A grid representing the dip of the structure plane (in degrees) | - |
| Dip direction grid (degrees) | grid, input, optional | D | A grid representing the dip direction of the structure plane (in degrees) | - |
| Output | TOBIA classes | grid, output | E | Resulting TOBIA classes (1-7) grid | - |
| TOBIA index | grid, output, optional | F | Resulting TOBIA index (-) grid | - |
| Options | Grid System | grid system | PARAMETERS_GRID_SYSTEM | - | - |
| Global structure dip (degrees) | floating point number | fB | Constant value if no raster set | Default: 45.000000 |
| Global structure dip direction (degrees) | floating point number | fC | Constant value if no raster set | Default: 90.000000 |
Command Line
Usage: saga_cmd ta_slope_stability 1 [-A ] [-B ] [-C ] [-D ] [-fB ] [-fC ] [-E ] [-F ]
-A: Slope grid (rad)
grid, input
-B: Aspect grid (rad)
grid, input
-C: Dip grid (degrees)
grid, input, optional
-D: Dip direction grid (degrees)
grid, input, optional
-fB: Global structure dip (degrees)
floating point number
Default: 45.000000
-fC: Global structure dip direction (degrees)
floating point number
Default: 90.000000
-E: TOBIA classes
grid, output
-F: TOBIA index
grid, output, optional