eve basin (southern France), also deposited at low latitudes. Additionally, we critically review published data from low latitude Permian red beds from the same basins. We focus on records with a sufficient number of samples, and acquire, whenever possible, the original data, or—as a second choice—parametrically sampled published site means. We test the distributions of these directions using a statistical secular variation field model (TK03.GAD). The angular standard deviation (ASD) of the virtual geomagnetic pole (VGP) distribution is a measure of (palaeo)secular variation, and we compare our values of ASD from the Permian red beds to those from lavas erupted in the last 5 Myr. Contrary to our previous studies, we now conclude that secular variation during the Permo-Carboniferous Reversed Superchron is slightly, but significantly, reduced at low latitudes compared with the recent field, as based on a latest compilation that supercedes earlier compilations. It also agrees with a new study, which found that PSV, at low palaeolatitudes during the Cretaceous Normal Superchron, was also significantly lower than in periods with frequent reversals.
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Haldan et al. (2009) studied this question.
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