harmonica.reduction_to_pole

harmonica.reduction_to_pole(grid, inclination, declination, magnetization_inclination=None, magnetization_declination=None, *, pad=True, pad_kwargs=None)

Calculate the reduction to the pole of a magnetic field grid.

Compute the reduction to the pole of regular gridded magnetic data using frequency domain calculations through Fast Fourier Transform.

Parameters:

gridxarray.DataArray

A two dimensional xarray.DataArray whose coordinates are evenly spaced (regular grid). Its dimensions should be in the following order: northing, easting. Its coordinates should be defined in the same units.

inclinationfloat in degrees

The inclination of the inducing Geomagnetic field.

declinationfloat in degrees

The declination of the inducing Geomagnetic field.

magnetization_inclinationfloat in degrees or None

The inclination of the total magnetization of the anomaly source. If None, the magnetization_inclination will be set equal to the inclination, neglecting remanent magnetization and self demagnetization. Default None.

magnetization_declinationfloat in degrees

The declination of the total magnetization of the anomaly source. If None, the magnetization_declination will be set equal to the declination, neglecting remanent magnetization and self demagnetization. Default None.

padbool, optional

If True, will add padding to the grid before taking the Fourier Transform and applying the filter and remove it after the inverse Fourier Transform. Adding padding usually helps reduce edge effects from signal truncation. Default is True.

pad_kwargsdict or None, optional

Any additional keyword arguments that should be passed to the xarray.DataArray.pad function in the form of a dictionary. If none are given, the default padding of 25% the dimensions of the grid will be added using the “edge” method.

Returns:

reduced_to_pole_gridxarray.DataArray

A xarray.DataArray after reduction to the pole of the passed grid.

See also

harmonica.filters.reduction_to_pole_kernel

References

[Blakely1995]

Examples using harmonica.reduction_to_pole

Reduction to the pole of a magnetic anomaly grid

Reduction to the pole of a magnetic anomaly grid

Tilt of a regular grid

Tilt of a regular grid