Figure F24. Orthogonal plots of the vector decay on AF demagnetization for four specimens located along the sampled U-channel. The example at 15 cm shows a low remagnetization easily removed at 5 mT and then a simple univectorial decay toward the origin with stable geomagnetic behavior. The examples at 21, 72 and 131 cm show no decay toward the origin but instead toward the southern hemisphere (reverse magnetization) with increased intensities. This characteristic depends from the fact that the AF is not able to demagnetize the material. An alternative explanation can be related to the presence of a strong drilling overprinting which remagnetized the weak magnetic component. NRM = natural remanent magnetization. A. Sample 325-M0041A-12R-1, 15 cm. B. Sample 325-M0041A-12R-1, 21 cm. C. Sample 325-M0041A-12R-1, 72 cm. D. Sample 325-M0041A-12R-1, 131 cm.
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