magnet {psd}

A single line of Project MAGNET horizontal field intensity

Description

The Project MAGNET mission provided a wealth of airborne-magnetometer data spanning the globe (Coleman, 1992). This dataset represents a single track of horizontal field intensities (a very small subset of the full collection!).

Format

A dataframe with 2048 observations on the following 4 variables.

km

Relative along-track distance, in kilometers. The first observation is at zero kilometers.

raw

Raw intensities, in nanotesla.

clean

Edited raw intensities, in nanotesla

mdiff

The difference between clean and raw intensities, in nanotesla.

Details

Raw and Clean Sets

There are non-real data points in raw MAGNET series; these are instrumental artefacts, and can severely affect power spectral density (PSD) estimates. A clean series has been included so that a comparison of PSDs may be made.

Some command like subset(magnet, abs(mdiff) > 0) can be used to identify the rows where edits have been made.

Source

Project MAGNET page: https://www.ngdc.noaa.gov/geomag/proj_mag.shtml

References

Coleman, R. J. (1992), Project Magnet high-level vector survey data reduction. In Types and Characteristics of Data for Geomagnetic Field Modeling, 3153, pp. 215-248.

See Also

pspectrum, Tohoku, hfsnm

Examples

data(magnet)
summary(magnet)