Neogene

Paleogene

Cretaceous

Jurassic

Triassic

Permian

Carboniferous

Devonian

Silurian

Ordovician

Cambrian

Neoproterozoic

Mesoproterozoic

Paleoproterozoic

Main source = Abduazimova, Z.M. (Ed.), 2001. Stratigraphic Dictionary of Uzbekistan. IMR (Institute of Mineral Resources), Tashkent, 580 pp. (In Russian) Translated to English by the GeoGPT group, Zhejiang Lab, Hangzhou, China--see About

Berkutlin Formation

Berkutlin Fm

Period:

Silurian

Age Interval:

Middle Llandovery, N5a

Province:
Nuratau

Type Locality and Naming

Along the Berkutli River, northern slope of the Chumkartau Mountains, Turkestan Ridge. M.M. Posokhova, A.N. Golikov, 1973. (165, p.51). The stratotype is in the upper reaches of the Berkutli River.

Synonym: Berkutlinskaya Suite, Беркутлинская св., Berkyutlin Fm

Lithology and Thickness

In the Lower part, there are black and dark-gray sericitized argillaceous slates with lenses of siltstone (aleurolites), fthanite-like rocks, and phosphorites; in the Upper part - gray, greenish-gray sandy siltstone (aleurolites) with layers of sericitized slates and coalified argillites. Thickness in different regions from 60 to 200-300 m.

Lithology Pattern:

Sandy_claystone

Relationships and Distribution

Lower contact

Conformably lies on the Guralash Fm

Upper contact

Conformably covered by the Uryuklin Fm.

Regional extent

Chumkartau Mountains.

GeoJSON

null

Fossils

Contains graptolites - Cephalograptus tubulariformis (Nich.), C. cometa (Gein.), Monograptus sedgwicki (Portl.), Demirastrites convolutus (His.), Rastrites peregrinus Barr. and others, Middle Llandovery.

Age

Middle Silurian, middle Llandovery substage. (165; 460).

Age Span:

Beginning stage:

Aeronian

Fraction up in beginning stage:

0.5

Beginning date (Ma):

439.54

Ending stage:

Aeronian

Fraction up in the ending stage:

1.0

Ending date (Ma):

438.59

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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