Conclusions

[115]  1. The Vendian rocks of the Lower Angara, Biryusa, and Central Sayan regions show the widely spread regional remagnetization of the rocks, which seems to have recorded the major tectonic and thermal events which developed at the southern and south-western margins of the Siberian Platform at the end of the Vendian to the beginning of the Cambrian.

[116]  2. As a result of our detailed study of the rocks of the Aisa, Chistyakova, and Moshakova formations (Ediacarian or Late Baikalian?), of the Redkolesnaya Formation (Late Ediacarian-Nemakit-Daldynian), as well as of the insular Ust-Tagul, Mota, and Irkutsk formations (Nemakit-Daldynian), we managed to identify the old magnetization which seems to have recorded the trend of the geomagnetic field that had existed during the time of the deposition of these rocks.

[117]  3. The paleomagnetic poles, corresponding to the primary magnetization trends, obtained for the rocks of the same ages in different regions or in different rock sequences do not differ statistically. This proves the absence of any large-scale tectonic rotations in the study areas, at least since the middle of the Taseeva time, and suggests that the resulting paleomagnetic poles can be referred for the whole of the Siberian Platform.

[118]  4. Our data contradict the IITPW hypothesis and support the assumption that the anomalous geomagnetic field had existed from the Late Vendian to the beginning of the Cambrian.

[119]  5. Our paleomagnetic data suggest that the later half of the Vendian and the beginning of the Cambrian witnessed an important tectonic rearrangement which resulted in the cardinal change of the Siberian Platform movement and possibly in that of the total planetary assemblage of the tectonic plates.

[120]  6. The results of this study proved that the Vendian segment of the Siberian of the APWP resided in the Indian Ocean and that the earlier views concerning the Pacific trends of the Late Riphean and Vendian poles were erroneous.


RJES

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