Aznek Formation

Aznek Fm

Period:

Devonian

Age Interval:

Famennian, K6, K8

Province:
Kyzylkum Region

Type Locality and Naming

Along the Aznek column, Aristantau Mountains, Central Kyzylkum. G. V. Balakin et al., 1972.

Synonym: Aznek Suite, Азнекская св.

Lithology and Thickness

Dolomites, alternating with dark gray and black dolomitized limestones and dark gray, gray limestones. Thickness 54-213m.

Lithology Pattern:

Dolomite

Relationships and Distribution

Lower contact

Along the bedding, it lies conformably on the Dzhanakhmet Fm (Janakhmet Fm)

Upper contact

It is also conformably, in parts transgressively, overlain by the Kocherbay Fm.

Regional extent

GeoJSON

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Fossils

Contains foraminifera - Archaeosphaera sp., Bisphaera cf. irregularis Bir., Tuberitina cf. maljavkini Mikhl., stromatoporoids - Labechia ex gr. radiosa Yavor., Pseudolabechia">Pseudolabechia ex gr. convexa Yavor., Rosenella irregularis Yavor. and others, characterizing the Famennian age of the deposits.

Age

Previously identified as Tournaisian. Along the decision of the MGS, it is assigned to the Upper Devonian (165; 495). On the State Geolmap-500 of Uzbekistan (460), it is shown as Lower Tournaisian.

Age Span:

Beginning stage:

Famennian

Fraction up in beginning stage:

0.5

Beginning date (Ma):

365.20

Ending stage:

Famennian

Fraction up in the ending stage:

1.0

Ending date (Ma):

359.30

Depositional setting

Depositional pattern:

Additional Information

Compiler:

Z.M.Abdazimova – In: GeoGPT translation of: “Abduazimova, Z.M. (Ed.), 2001. Stratigraphic Dictionary of Uzbekistan. IMR (Institute of Mineral Resources), Tashkent, 580 pp. (In Russian)”