Un nuevo programa basado en Matlab para análisis espectral de datos magnetométricos

NÚÑEZ DEMARCO, PABLO; PREZZI, CLAUDIA BEATRIZ; SÁNCHEZ BETTUCCI, LEDA

Congreso; Latinmag Quinta Reunión Bienal de la Asociación Latinoamericana de Paleomagnetismo y Geomagnetismo; 2017

We developed a new MatLab based program that automatically computes the 2-D spectral analysis of magnetic maps, estimates the Curie point depth, the geothermal gradient and heat flux according to the methods established by Spector & Grant (1970), Bhattacharyya & Leu (1977), Okubo et al. (1985) and Tanaka et al. (1999). The program loads the magnetic data, interpolates the missing data if required, and divides the map in subregions according to the size established by the user. Also, different levels of overlapping between subregions (ranging from 0% to 99.9%) are tested simultaneously, according to the user customization. The 2-D FFT power spectrum is calculated for each subregion. The centroid and top depth of magnetic sources is derived from the slopes of the longest and second-longest wavelength of the radial averaged frequency-scaled power spectra and the radial averaged power spectra respectively. The Curie point depth is derived from top and centroid depths (Okubo et al., 1985) and the geothermal gradient calculated. All the data is plotted in different visualization forms. In addition, information about the procedure is visualized in order to validate it. This information includes statistical parameters, correlation coefficients and fast visualization of the linear adjustments. This program was tested and compared with the results of other softwares like Oasis Montaj, obtaining an improvement in resolution and substantial reduction in processing time.