Ustʹ Pinega Formation

The formation was first established and described from the core of the Ust-Pinega borehole drilled in the settlement of Ust-Pinega, Arkhangelsk Region of Russia, where its thickness is 284 m. Its natural outcrops within the same region are known from the Onega Peninsula and the Winter Coast of the White Sea, as well as from small, isolated outcrops in the basin of the Onega River and on the northern slope of the Vetreny Poyas (Windy Belt) Ridge. Currently, the Ust' Pinega Formation and its subformations remain the official stratigraphic scheme used on state geological maps of Russia. == Dating ==

The Lyamtsa, Verkhovka and Vaizitsa Subformations contain volcanic ashes. Zircon U-Pb dating of volcanic tuffs from the Verkhovka and Vaizitsa beds has yielded ages of and , respectively. Furthermore, an Rb–Sr age of was obtained for clays of the Arkhangelsk Subformation. == Paleobiota ==

The Ustʹ Pinega Formation is home to many rare and common Ediacaran fauna, from the well known motile forms such as Dickinsonia and Kimberella, to the rarer, more elusive forms like Ventogyrus and Zolotytsia. All forms within this formation are preserved in layers of ash beds, which are not only good at preserving the fine exterior details of organisms, but also their internals, like Burykhia. Proarticulata Petalonamae Trilobozoan Cnidarian Chordata Annelida incertae sedis Flora Ichnogenera == See also ==