ИСТИНА

Lots of paleomagnetic data shows a low-latitude position of ancient platforms during Neoproterozoic glaciations. In terms of the "Snowball Earth" hypothesis it means, that during this time Earth was totally covered by ice few times. Theoretical calculation shows inevitable closure of polar ice-caps after they reach near 300 latitudes in response to the positive feedback loop between thermal balance and albedo of planet. However, there are no paleomagnetic data showing a high-latitude position for some continent at this time. It can be explained by absence of continental blocks in high latitudes, or by development of glaciations only in low latitudes. The latter is developed in G. Williams' "anti-Snowball" works and can be explained by the dramatic change of the Earth's obliquity angle. In Neoproterozoic sedimentary sequences of Siberia few glacial horizons are known, and their origin is believed to be related with global glaciations. For two of them, we obtained paleomagnetic data indicating the low-latitude position of the Siberian platform during glaciation. Particularly calculated paleolatitude for overlapped by tillites Vandadyk fm. is ~ 90. Paleolatitude for Nichatka fm. containing glacial deposits is ~ 00. Such results are “pros” for “Snowball Earth” hypothesis from one hand. From another hand the results from Nichatka fm. are obtained in deposits resembled modern varves (seasonal-controlled periglacial deposits). We argue this type of varves cannot be formed nor in equatorial areas, nor under global-glaciation conditions. Therefore, the obtained data finds no explanation in terms of “Snowball Earth” hypothesis and may indicate inconsistency of Geocentric Axial Dipole model for Neoproterozoic geomagnetic field.