Yakutia, Siberian Platform, Nepa-Botuoba region, boreholes Zapad 844 (Ediacaran of Russian Federation)

Where: Yakutia, Russian Federation (61.1° N, 110.9° E: paleocoordinates 35.9° S, 0.6° E)

• coordinate estimated from map

When: Khamaka Formation, Vendian (635.0 - 541.0 Ma)

• Late Vendian. Ediacaran. The acritarchs in the Khamaka Formation are considered to indicate an Ediacaran age. The study confirms the broad environmental and geographical distribution of Neoproterozoic (late Vendian) plankton. and that they are diverse in rocks reflecting a ronge of depositional settings.

• group of beds-level stratigraphic resolution

Environment/lithology: deep subtidal; lithified, gray mudstone and lithified shale

• The acritarchs derive from siliciclastic rocks of the Khamaka Formation, the lowermost part of the Vendian to Cambrian sedimentary succession in the central part of the Siberian Platform. Assemblages from the lowermost part of the sedimentary succession in the Nepa-Botuoba region. The lower part of the succession in the study area consists of siliciclastic rocks of variable thickness succeeded by thick carbonates, which are, in turn, overlain by evaporites. The siliciclastic deposits consist of sandstones, mudstones and shales ranging in thickness from approximately 30 to 300m. Occasionally, conglomerates occur at the base of the sequence. Sandstones are predominant, forming thick units with numerous discontinuity surfaces and unconformities.

•Mudstones occur as thin intercalations in the sandstones or as discrete beds reaching 20 to 40 m in thickness. Carbonates overlying the siliciclastic portion of the sequence range in thickness from 170 to 400 m. They consist

•largely of dolostones or more rarely limestones, and clayey dolostones(Grausman and Zhernovskjj 1989; Rudavskaya and Vasileva 1989). The carbonate succession is overlain by thick (250 m)evaporites, comprising mainly of halite, with lesser amounts of anhydrite.

Size classes: mesofossils, microfossils

Primary reference: M. Moczydlowska, G. Vidal, and V. A. Rudavskaya. 1993. Neoproterozoic (Vendian) Phytoplankton from the Sieberian Platform, Yakutia. Palaeontology 36(3):395-521 [W. Kiessling/M. Krause]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 140116: authorized by Wolfgang Kiessling, entered by Mihaela Krause on 01.03.2013

Creative Commons license: CC BY (attribution)

Taxonomic list

Tanarium tuberosum Moczydlowska et al. 1993