Vendian

VENDIAN, Vendian system, Vendian complex (from the name of the ancient Slavic tribe, namely, Wendy, Wends * EN: Vendian; DE: Wendien, Wendium; FR: vendien; ES: vendiano; RU: венд) is the top stratigraphic sub-division of the Proterozoic, which is immediately preceding the Cambrian system, and is near to it according to the stratigraphic rank. The approximate age interval is from 680 ± 20 to 570 ± 20 million years. In the paleozoological and paleogeographic terms, the Vendian is clearly separated from the Riphean and the Cambrian, but generally gravitates more to the Phanerozoic than to the Riphean. The typical section to the west of the Eastern European craton is represented by the terrigenous depositions, and includes the Vilchansk series (the tillites of the Lapland glaciation), Volyn series, Valdai series, and the layers with the Sabelliditida fossils (the Rovno horizon of the Baltic series). During the 1981, on the Olenek uplift (of the North-Eastern Siberian craton), there has been identified the most important reference section of the Vendian within the carbonate facies. The planetary significance of the Vendian comprises the combination of the typical paleozoological characteristics with the Yudomian complex of the phytoliths, and comprises the immediate contact of the Vendian and the Cambrian within the continuous section. For the Vendian, there is everywhere characteristic the after-tillites most ancient fauna of the soft-bodied invertebrates of the Ediacaran type; there may be found the numerous remains of the aquatic plants (vendotaenids), phytoplankton, and phytolites.

The Vendian has been identified by the Soviet geologist B. S. Sokolov during the 1950, and has been traced on all the continents. The stratigraphic analogues of the Vendian are the Yudomian series within the Eastern Siberia, the "blue" series stratum within the Southern China, the Conception series within Canada, the upper part of the Adelaidean within Australia, the Nama group within the Republic of South Africa, the Charnian series on the British Isles. The depositions of the Vendian are promising for petroleum and gas (for example, within the Eastern Siberia).