---
name: "grdvolume"
section: "1"
platform: "linux"
package: "gmt-manpages"
version: "3.4-1"
release: "Debian 3.0 (Woody)"
platforms: ["linux"]
url: "https://new.carta.tech/grdvolume"
---

# grdvolume(1)

Calculating volume under a surface within a contour

## NAME

grdvolume - Calculating volume under a surface within a contour

## SYNOPSIS

**grdvolume** *grdfile* \[ **-C***cval* or **-C***low/high/delta* \] \[ **-L***base* \] \[ **-R***west/east/south/north*\[**r**\] \] \[ **-S**\[**k**\] \] \[ **-T** \] \[ **-V**\[**l**\] \] \[ **-Z***fact*\[/*delta*\] \]

## DESCRIPTION

**grdvolume** reads a 2-D binary grd file and calculates the volume contained between the surface and the plane specified by the given contour (or zero if not given). Alternatively, specify a range of contours to be tried and **grdvolume** will determine the volume and area inside the contour for all contour values. The contour that produced the maximum mean height (volume/area) is reported as well. This feature may be used with **grdfilter** in designing an Optimal Robust Separator \[*Wessel*, 1998\].

- *grdfile*

  The name of the input 2-D binary grd file.

## OPTIONS

No space between the option flag and the associated arguments.

- **-C**

  find area and volume inside the *cval* contour. Alternatively, search using all contours from *low* to *high* in steps of *delta*. \[Default returns entire area and volume of grid\].

- **-L**

  Also add in the volume from the level of the contour down to *base* \[Default base is contour\].

- **-S**

  Convert degrees to meters, append **k** for km \[Default is Cartesian\].

- **-T**

  Use curvature minimum rather than maximum height to find best contour value (when contour search is selected with **-C**).

- **-R**

  *west, east, south,* and *north* specify the Region of interest. To specify boundaries in degrees and minutes \[and seconds\], use the dd:mm\[:ss\] format. Append **r** if lower left and upper right map coordinates are given instead of wesn.

- **-V**

  Selects verbose mode, which will send progress reports to stderr \[Default runs "silently"\]. Append **l** to see all the results for each contour level tested (when contour search has been selected).

- **-Z**

  Optionally subtract *shift* before scaling data by *fact*. \[Default is no scaling\]. (Numbers in **-C, -L** refer to values after this scaling has occurred).

## EXAMPLES

To determine the volume in km^3 under the surface hawaii\_topo.grd (height in km), try\

grdvolume hawaii\_topo.grd **-Sk**\

To find the volume between the surface peaks.grd and the contour z = 250, use\

grdvolume peaks.grd **-Sk** **-C**250\

To search for the contour, between 100 and 300 in steps of 10, that maximizes the ratio of volume to surface area for the file peaks.grd, use\

grdvolume peaks.grd **-Sk** **-C**100/300/10 \> results.d\

To see the areas and volumes for all the countours in the previous example, try\

grdvolume peaks.grd **-Sk -Vl** **-C**100/300/10 \> results.d

## SEE ALSO

*gmt*(l), *grdfilter*(l)

## REFERENCES

Wessel, P., 1998, An empirical method for optimal robust regional-residual separation of geophysical data, *Math. Geol., 30(4)*, 391-408.