Worldwide Instantaneous Values of Geomagnetic Components D, H, and Z or X, Y, and Z at 2.5-minute Intervals from 1964 to 1974
This data file is comprised of instantaneous values of the geomagnetic components D, H, and Z or X, Y, and Z at 2.5-minute intervals. These values were derived from analog recordings (magnetograms) with the aid of semi-automatic digitizing equipment from a worldwide network of about 75 observatories.