GEOSCAN, résultats de la recherche


TitreReduction of potential field data to a horizontal plane
AuteurPilkington, M; Urquhart, W E S
SourceGeophysics vol. 55, no. 5, 1990 p. 549-555,
Séries alt.Commission géologique du Canada, Contributions aux publications extérieures 15289
ÉditeurSociety of Exploration Geophysicists
Documentpublication en série
Mediapapier; en ligne; numérique
Lat/Long OENS -68.0000 -66.0000 49.0000 48.0000
Sujetsméthodes analytiques; levés aéromagnétiques; levés magnétiques; méthodes statistiques; levés géophysiques; topographie; géophysique; géomathématique
Illustrationscharts; formulae
Résumé(disponible en anglais seulement)
Most existing techniques for potential field data enhancement and interpretation require data on a horizontal plane. Hence, when observations are made on an irregular surface, reduction to a horizontal plane is necessary. To effect this reduction, an equivalent source distribution that models the observed field is computed on a mirror image of the observation surface. This irregular mirror image surface is then replaced by a horizontal plane and the effect of the equivalent sources is computed on the required horizontal level. This calculated field approximates the field reduced to a horizontal plane.The good quality of this approximation is demonstrated by two-dimensional synthetic data examples in which the maximum errors occur in areas of steep topographic gradients and increased magnetic field intensity. The approach is also applied to a portion of a helicopter-borne aeromagnetic survey from the Gaspe region in Quebec, Canada, where the results are a horizontal shifting of anomaly maxima of up to 150 m and changes in anomaly amplitudes of up to 100 nT.