Gravity Earth (GFILT)

Use the Gravity Earth Filter option to apply a gravity earth filter.

Gravity Earth Filter dialog options

Depth to top of layer	Specify the depth to top of layer in ground units.
Depth to bottom of layer	Specify the depth to bottom of layer in ground units.

Application Notes

Use the Gravity Earth Filter to calculate the gravitational field of the horizontal earth layer that resides between two user defined depths. This filter is implemented to be used by GM-SYS.

When r = 0,

Where:

G	Gravitational constant.
z1	Depth to the top of the density layer, in ground units, of the earth. Must be positive for layers above calculation level.
z2	Depth to the bottom of the density layer, in ground units, of the earth. Must be positive for layers above calculation level.

Wavenumber domain variable definition

k	Wavenumber domain increment, used to depict a radially symmetrical variable.	where: np is the number of points cs is the cell size
u	X component in the wavenumber domain.	k = 2π ( i μ+j ν )
v	Y component in the wavenumber domain.
r	Radial component in the wavenumber domain.	also 2πk
θ	Polar component in the wavenumber domain.

Ground_unit is the survey ground units as defined in your grid (e.g. metre or feet). Ground units may be left undefined.

Reference