i.gravity

Bouguer gravity anomaly computation (full slab).

i.gravity gravity_obs=name elevation=name latitude=name flight_azimuth=name flight_velocity=name slab_density=name terrain_corr=name output=name [--overwrite] [--verbose] [--quiet] [--qq] [--ui]

Example:

i.gravity gravity_obs=gravity_obs elevation=dem latitude=lat flight_azimuth=flight_azimuth flight_velocity=flight_velocity slab_density=slab_density terrain_corr=terrain_corr output=name

grass.script.run_command("i.gravity", gravity_obs="gravity_obs", elevation="dem", latitude="lat", flight_azimuth="flight_azimuth", flight_velocity="flight_velocity", slab_density="slab_density", terrain_corr="terrain_corr", output, overwrite=False, verbose=False, quiet=False, superquiet=False)

Example:

gs.run_command("i.gravity", gravity_obs="gravity_obs", elevation="dem", latitude="lat", flight_azimuth="flight_azimuth", flight_velocity="flight_velocity", slab_density="slab_density", terrain_corr="terrain_corr", output="name")

Parameters

Command linePython (grass.script)

gravity_obs=name [required]
    Name of the observed gravity map [mGal]
    Default: gravity_obs
elevation=name [required]
    Name of the elevation map [m]
    Default: dem
latitude=name [required]
    Name of the latitude map [dd.ddd]
    Default: lat
flight_azimuth=name [required]
    Name of the flight azimuth map (clockwise from North) [dd.ddd]
    Default: flight_azimuth
flight_velocity=name [required]
    Name of the flight velocity [kph]
    Default: flight_velocity
slab_density=name [required]
    Name of the slab density [kg/m3]
    Default: slab_density
terrain_corr=name [required]
    Name of the terrain correction map []
    Default: terrain_corr
output=name [required]
    Name of the Bouguer gravity anomaly [mGal]
--overwrite
    Allow output files to overwrite existing files
--help
    Print usage summary
--verbose
    Verbose module output
--quiet
    Quiet module output
--qq
    Very quiet module output
--ui
    Force launching GUI dialog

gravity_obs : str, required
    Name of the observed gravity map [mGal]
    Used as: input, raster, name
    Default: gravity_obs
elevation : str, required
    Name of the elevation map [m]
    Used as: input, raster, name
    Default: dem
latitude : str, required
    Name of the latitude map [dd.ddd]
    Used as: input, raster, name
    Default: lat
flight_azimuth : str, required
    Name of the flight azimuth map (clockwise from North) [dd.ddd]
    Used as: input, raster, name
    Default: flight_azimuth
flight_velocity : str, required
    Name of the flight velocity [kph]
    Used as: input, raster, name
    Default: flight_velocity
slab_density : str, required
    Name of the slab density [kg/m3]
    Used as: input, raster, name
    Default: slab_density
terrain_corr : str, required
    Name of the terrain correction map []
    Used as: input, raster, name
    Default: terrain_corr
output : str, required
    Name of the Bouguer gravity anomaly [mGal]
    Used as: output, raster, name
overwrite: bool, optional
    Allow output files to overwrite existing files
    Default: False
verbose: bool, optional
    Verbose module output
    Default: False
quiet: bool, optional
    Quiet module output
    Default: False
superquiet: bool, optional
    Very quiet module output
    Default: False

DESCRIPTION

i.gravity calculates the Bouguer gravity anomaly (after Mussett and Khan).
Bouguer anomaly computation require:

g_obs=observed gravity
freeair_corr=free air correction
bouguer_corr=bouguer correction
terrain_corr=terrain correction
latitude_corr=latitude correction
eotvos_corr=eotvos correction

NOTES

International Gravity Formula (mGal), lambda=latitude (dd)
Eotvos correction (mGal), v=velocity (kph), lambda=latitude (dd), alpha=direction of travel measured clockwise from North
Free air Correction (mGal), h=height (m)
Bouguer Correction (mGal), rho=density of slab (Mg/m3), h=height (m)

For more details on the algorithms see [1].

REFERENCES

[1] Mussett, A.E. and Khan, M.A, M.A. Looking into the Earth: An Introduction to Geological Geophysics.

AUTHOR

Yann Chemin, University of London at Birkbeck, United Kingdom.

SOURCE CODE

Available at: i.gravity source code (history)
Latest change: Friday Feb 21 10:10:05 2025 in commit 7d78fe3