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Magnetização remanescente: um parâmetro crucial para a interpretação e modelamento de anomalias magnéticas em território brasileiro

Remanent magnetization is often neglected in data interpretation, probably for the difficulty on working with it. In most of the cases, both in academic works and professional models in mining and oil industry, prevails the assumption that remanence is irrelevant or inexistent, and the induced effect is the only one considered. The present paper shows that using this parameter is particularly important on Brazilian anomalies, where magnetic latitudes are low, and try to provide tools for the use of the remanence information. In the article we discuss the use of common geophysical techniques, analytic signal and reduction to the pole in Brazilian anomalies due to rocks with and without remanence. Then we presented a method to estimate the total magnetic direction from a magnetic anomaly, from which it is possible to extract the total magnetization parameter, and consequently the resultant sum vector after induced and remanent parameters. Finally, we present a methodology for the use of remanent information to determine the age of the source rocks.

remanent magnetization; magnetic anomalies; interpretation; paleomagnetic virtual poles


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