Geologicheskii Vestnik

The paper presents the results of a paleomagnetic study of the red-colored sandstones of the lower part of the Late Ediacaran Zigan Formation, previously carried out by the authors and other researchers with the aim of establishing the paleoposition of the Baltic craton at the end of the Neoproterozoic. The laboratory paleomagnetic studies were carried out in accordance with the currently generally accepted methods, which includes thermal demagnetization and component analysis of selected directions of magnetization. For about 200 samples, it was possible to isolate the bipolar high-temperature magnetization component, which is of primary origin, as evidenced by a positive reversal test and a regional correspondence test. More than 20 inversions of the geomagnetic fi eld were identifi ed in the section with a thickness of about 80 m. Such an ultrahigh frequency of inversions is observed only in two other Late Ediacaran complexes of deposits on the Earth. The opinion of J. Meert et al. concerning a possible infl uence of the anomalous state of the geomagnetic fi eld on the subsequent largest biosphere restructuring in the history of the Earth is given.

paleomagnetism, high-temperature component of magnetization, Zijderveld diagram, inversion of the geomagnetic fi eld, Ediacaran, Zigan Formation, Southern Urals

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