Estudio combinado paleomagnético y petromagnético de flujos de lava asociados al rift Tepic-Zacoalco emitidos durante los crhones geomagnéticos Gauss y Gilbert

• Main Author: Ulises Demian Díaz Ortega
• Other Authors: Mikhail Ostrooumov, Avtandil Gogichaishvili
• Format: Master Thesis
• Language: Spanish
• Published: Universidad Michoacana de San Nicolás de Hidalgo 2019
• Subjects: info:eu-repo/classification/cti/1; INICIT-M-2019-0985; Paleopolos; Ritf; Tectónica; Geomagnetic Pole
• Online Access: http://bibliotecavirtual.dgb.umich.mx:8083/xmlui/handle/DGB_UMICH/4429

Instituto de Investigaciones en Ciencias de la Tierra. Maestría en Geociencias y Planificación del Territorio Using paleomagnetique techniques it was possible to determine 17 directions from a total of 21 study sites, of which 4 have normal polarity, 8 reverse polarity and 5 intermediate polarities, the last ones have a cone of certainty that ranges from 2.5 to 22°. The samples come from lava flows located along the Tepic-Zacoalco Rift. Which have high quality radiometric tests that reportages between 3 and 5Ma. Rock magnetism tests were performed which allow to obtain the variability of magnetic susceptibility as a function of temperature (kT curves), most of the samples have a single phase close to 570 ° C which is representative of poor in titanium titanomagnetite. In the case of sites that have two phases, the first one is located around 360 ° C, while the second and dominant phase is approximately 560 ° C which is consistent with titanomagnetite with high and low content in titanium. By discarding the intermediate polarities and inverting the reverse polarities, it was possible to calculate the paleomagnetic average with Dec = 347.4 °, Inc = 29.2 °, N = 12, α95 = 9.7 °. The position of virtual geomagnetic pole the obtained is PLat = 77.9 ° N, PLong = 160.3 ° E, A95 = 6.83 °, N = 21. Comparing the pole obtained with the apparent polar drift curves for North America (APWP) published by Besse and Courtillot (2002) and Torsvik et al., (2008) which were calculated for a 5Ma window, a significant difference is observed, which can be attributed to a possible independent displacement of the Jalisco Block with respect to the North American plate. Considering the radiometric ages of each sample and the determined polarity, it was possible to construct a column of geomagnetic polarities. Mediante técnicas paleomagnéticas fue posible determinar 17 direcciones de un total de 21sitios de estudio, de las cuales 4 tienen una polaridad normal, 8 polaridad invertida y 5 con polaridades intermedias, de estas últimas ...