Kokyar Formation

Kokyar Fm

Period:

Cretaceous

Age Interval:

Hauterivian-Aptian (?), F6

Province:
Fergana

Type Locality and Naming

By Koki-Yar, East Fergana. A.V. Sochava, 1965 (434, p.14). Stratotype in the lower reaches of the Tar River. Fifth formation in Changet Gr

Synonym: Kokyarskaya Formation, Кокьярская св.

Lithology and Thickness

Red-colored sandstones and clays with rare layers of blue siltstone (aleurolites) and clays. Thickness 200-680m

Lithology Pattern:

Clayey sandstone

Relationships and Distribution

Lower contact

Conformably overlies the Chalmin Fm

Upper contact

Conformably overlain by the Klaudzin Fm

Regional extent

Notes on the foothills of the Fergana Range. Included in the Changet Gr

GeoJSON

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Fossils

Contains freshwater bivalve mollusks Trigonioides kodairaiformis Mart., Nakamuranaia chingshanensis Sur., Plicatounio naktongensis Kob. et Suz.

Age

Conditionally attributed to the Hauterivian-Aptian (?)

Age Span:

Beginning stage:

Hauterivian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

132.60

Ending stage:

Aptian

Fraction up in the ending stage:

0.5

Ending date (Ma):

117.30

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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