Evaluación preliminar del campo geomagnético de referencia internacional IGRF-1990 para México y anomalías magnéticas corticales
Main Article Content
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.
Article Details
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
References
BARRACLOUGH, D. R., 1987. International Geomagnetic Reference Field: the fourth generation. Phys. Earth. Planet. Inter., 48, 279-292, 1987. DOI: https://doi.org/10.1016/0031-9201(87)90150-6
CAÑON-AMARO, C., E. HERNANDEZ-QUINTERO, H. NOLASCO-CHAVEZ, A. OROZCO-TORRES y G. ALVAREZ-GARCIA, 1993. Cartas Magnéticas de Ia Republica Mexicana para Ia época 1990.0, Escala 1: 5000,000. Instituto de Geofísica-INEGI, México.
CAÑON-AMARO, C., 1984. Variaciones de Ia declinación magnética de Ia República Mexicana desde 1630. Comunicación Técnica, No. 38, IGF-UNAM.
COHEN, Y. y J. ACHACHE, 1990. New global vector magnetic anomaly maps derived from MAGSAT data. J. Geophys. Res. 95, B7, 10783-10800. DOI: https://doi.org/10.1029/JB095iB07p10783
COMMITTEE FOR THE MAGNETIC ANOMALY MAP OF NORTH AMERICA, 1987. The magnetic anomaly map for North America (scale 1:5000,000), a publication of the Decade of North American geology. The American Society of Geology, Inc., Boulder Colorado.
COUNIL, J. L. J. ACHACHE y A. GALDEANO, 1989. Long-wavelength magnetic anomalies in the Caribbean: Plate boundaries and allochthonous continental blocks. J. Geophys. Res., 94, B6, 7419-7431. DOI: https://doi.org/10.1029/JB094iB06p07419
DAWSON, E. y L. R. NEWITT, 1978. IGRF comparisons. Phys. Earth Planet. Inter., 16, 1-6. DOI: https://doi.org/10.1016/0031-9201(78)90079-1
DAWSON, E. y L. R. NEWITT, 1982. Comparison of IGRF models with North American magnetic data. J. Geomag. Geoelectr., 34, 393-400. DOI: https://doi.org/10.5636/jgg.34.393
FREY, H., 1982. MAGSAT scalar anomaly distribution: The global perspective. Geophys. Res. Lett., 9, 4, 227-280. DOI: https://doi.org/10.1029/GL009i004p00277
GODINEZ-LUNA, A., 1990. Valores magnéticos para el año de 1987. Obs. Magnético de Teoloyucan, Datos Geof. Serie C, Instituto de Geofísica, UNAM, México, 46 pp.
HINZE, H. J., R. R. B. VON FRESE, M. B. LONGACRE y L. W. BRAYLE, 1982. Regional magnetic and gravity anomalies of South America. Geophys. Res. Lett., 9, 4, 314-1317. DOI: https://doi.org/10.1029/GL009i004p00314
IAGA DIVISION I WORKING GROUP 1 (D. R. Barraclough, Chairman), 1988. International Geomagnetic Reference Field Revision, 1987. Geophys. J. 93, 187-189. DOI: https://doi.org/10.1111/j.1365-246X.1988.tb01397.x
INTERNATIONAL ASSOCIATION OF GEOMAGNETISM AND AERONOMY (IAGA), Division V. Working group 8. Analysis of the main field and secular variation (R. A. Langel, Chairman), 1992. International Geomagnetic Reference Field, 1991 revision. Geophys. J., 108, 945-946.
LANGEL, R. A., J. D. PHILLIPS y R. J. HORNER, 1982. Initial scalar anomaly map from MAGSAT. Geophys. Res. Lett., 9, 4, 269-272. DOI: https://doi.org/10.1029/GL009i004p00269
LANGEL, R. A., C. C. SCHNETZLER, J. D. PHILLIPS y R. J. HORNER, 1982. Initial vector anomaly map from MAGSAT. Geophys. Res. Lett., 9, 4, 273-276. DOI: https://doi.org/10.1029/GL009i004p00273
PEDDIE, N. W., 1983. International Geomagnetic Reference Field-Its evolution and the difference in total field intensity between new and old models for 1965-1980. Geophys., 48, 12, 1691-1696. DOI: https://doi.org/10.1190/1.1441450
SANDOVAL, O. R., 1950. Elementos magnéticos en Ia República Mexicana. Servicio Geomagnético, Instituto de Geofísica, UNAM (México), pp. 182.
URRUTIA-FUCUGAUCHI, J. y J. O. CAMPOS-ENRIQUEZ. Geomagnetic secular variation in central Mexico since· 1923 AD and comparison with 1945-1990 IGRF models. J. Geomag. Geoelectr., 45, 3. DOI: https://doi.org/10.5636/jgg.45.243
VASSAL, J., 1987. Secular change in the geomagnetic fields in west Africa for thirty years: Comparison with fourth generation IGRF models. J. Geomag. Geoelectr., 39, 699-707. DOI: https://doi.org/10.5636/jgg.39.699