Description
Average divide-minus-floor relief and divide floorWidth by that mean relief.
Geomorphic geometry uses lengths, areas, volumes, and dimensionless shape ratios to summarize a feature. Grain axes, channel dimensions, and angular units need explicit definitions because similar field names can describe different measurements.
Average divide-minus-floor relief and divide floorWidth by that mean relief.
When to use this tool
Use Valley Width Depth Relative Index when you need a geometric summary of a supplied landform or sediment measurement.
How to use the tool and how it works
- Enter floorWidth, leftDivideElevation, rightDivideElevation, floorElevation. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read meanRelief, widthHeightRatio. Use the output convention below.
Require nonnegative floorWidth, each divide elevation at least floorElevation, and positive combined relief. Average divide-minus-floor relief and divide floorWidth by that mean relief.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| floorWidth | Floor Width | Required. Finite number; minimum 0. |
| leftDivideElevation | Left Divide Elevation | Required. Finite number. |
| rightDivideElevation | Right Divide Elevation | Required. Finite number. |
| floorElevation | Floor Elevation | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| meanRelief | Mean Relief | Required. Finite number. |
| widthHeightRatio | Width Height Ratio | Required. Finite number. |
{
"input": {
"floorWidth": 100,
"leftDivideElevation": 200,
"rightDivideElevation": 180,
"floorElevation": 100
},
"output": {
"meanRelief": 90,
"widthHeightRatio": 1.1111111111111112
}
}Limitations and assumptions
- All lengths share units and datum; this is a supplied valley width-height index without identifying valley boundaries, landscape process, or tectonic activity.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Inspect the measured feature and sampling method for the intended geometric definition. Use a spatial model or complete distribution when a single shape ratio or local term is insufficient.
References
Similar or alternative tools
- Valley Width Reference Height Gap
Multiply suppliedWidthGradient by referenceHeight-measuredHeight and add that adjustment to width.
- Channel Sinuosity Valley Reference Ratio
Return channel/valley, channel/straight, and valley/straight ratios.