Evaluación preliminar del campo geomagnético de referencia internacional IGRF-1990 para México y anomalías magnéticas corticales

Abstract

A regional comparison between the International Geomagnetic Reference Field (IGRF) for 1990 and the observed geomagnetic field derived from measurements taken at 51 localities is reported. The IGRF model provides a satisfactory reference field for Mexico. The differences between the IGRF model and the observed field seem to define regional anomalies. The total field mean difference is 10.6 nT, with a root mean square (RMS) deviation of 206 nT. Corresponding mean differences for the horizontal component and the declination are 24.4 nT and -0.6', with RMS deviations of 116 nT and 18.7', respectively. Long-wavelength features in the total field correlate with aeromagnetic and satellite magnetic anomalies, which suggests a possible association with crustal sources.