DETERMINATION OF VERTICAL MAGNETIC-ANOMALIES AND EQUIVALENT LAYER FORTHE EUROPEAN REGION FROM THE MAGSAT MEASUREMENTS

Two procedures are developed and discussed: the determination of the v ertical magnetic anomalies derived from the Magsat data and the determ ination of magnetic moment of the Earth's surface layer derived from t he vertical magnetic anomalies. The selected and corrected Magsat data are interpolated for a sphere of radius 6771 km (elevation 400 km) fo r the interval of 30 degrees-60 degrees N in latitude, and for the int erval of -12 degrees-30 degrees in longitude in a spherical grid of 0. 2 degrees. The interpolation was done with the application of the Gaus sian low-pass filter. The band of wavelength of the interpolated data is 1200-3000 km. The magnetic dipole moment of the equivalent layer is determined for the European region from the interpolated magnetic ano malies. It was assumed that the magnetic dipoles of the equivalent lay er were positioned on the surface of the earth (given by the radius 63 71.2 km), and oriented in the direction of the earth's main magnetic f ield. The magnetic dipole moment is determined by the gradient method for the solution of a minimum problem. (C) 1998 Elsevier Science B.V.