What happened to the high-latitude palaeomagnetic poles?

MANY apparent polar paths for the Precambrian have been published recently. A striking feature of these paths, besides their spaghetti-like appearance, is their bias for the equatorial zone, or their apparent aversion to high latitudes1–3. Does this mean that contrary to the present pole, the ancient pole had a much greater affinity for the equatorial region? Perhaps high latitude poles do not exist, or they are not reported, or they are discriminated against in construction of polar paths. From data given here it seems that only the Pleistocene, the late Palaeozoic4 and Aphebian glacial deposits5,6 were truly formed in high latitudes. We discuss here whether some other mechanism is needed to explain the implied low latitude of deposition of other glacial deposits, and whether all these other deposits were genuinely polar but the palaeomagnetic record, as presently known, is deficient in high latitude poles. Difficulty in finding high latitude poles could arise from one or more of the following causes: inadequate (and biased) sampling; tectonic effect; and interpretation of high latitude poles.