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

Chimkurgan Formation

Chimkurgan Fm

Period:

Devonian

Age Interval:

Emsian–early Eifelian, N3

Province:
Nuratau

Type Locality and Naming

By the village of Chimkurgan, the area of the village of Chimkurgan, the Pistalitau Mountains, the northern foothills of the North Nuratau Range. P.N. Podkopaev in 1959 (1961; 460, p.108) in the volume of Serpukhov-n. Bashkir n.-sr. Carbon.

Synonym: Chimkurgan Suite, Чимкурганская св.

Lithology and Thickness

Basalts, andesibasalts and their tuffs with layers and lenses of claystone (argillites), siltstone (aleurolites), jaspers and marbled limestones. Thickness about 1200 m.

Lithology Pattern:

Volcanics

Relationships and Distribution

Lower contact

Contacts with the surrounding rocks are tectonic (Usmanov et al., 1999f.) In the monograph (165), the lower boundary is unknown.

Upper contact

V.P. Vashchenko et al. (1980) believe that the contacts with the overlying Uchkulach Fm are normal stratigraphic. The upper boundary is transgressive with the Lower Uchkulach Fm

Regional extent

Northern foothills of the North Nuratau Range, south-eastern end of the Pistalitau Mountains.

GeoJSON

null

Fossils

Contains Tentaculites Stiliolina cf. Fissurella (Hall.), Nowakia sp. (cf. sulcata Roemer), Metastiliolina sp. (cf. striatissimaBouček et Prantl.); conodonts - Polygnathus cf. linguiformis bultyncki Wedd. and others.

Age

The presence of P. linguiformis and N. sp. (cf. sulcata) allows the age of the formation to be determined as within the Emsian–early Eifelian (165). On the State Geological Map-500 of Uzbekistan (460) - late Early to early Middle Devonian, contacts are tectonic.

Age Span:

Beginning stage:

Emsian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

410.51

Ending stage:

Emsian

Fraction up in the ending stage:

0.5

Ending date (Ma):

402.41

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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