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

Uchkulach Formation

Uchkulach Fm

Period:

Devonian

Age Interval:

Eifelian-Givetian, N3

Province:
Nuratau

Type Locality and Naming

By the village of Uchkulach, Khanbandytau Mountains, northern foothills of the N. Nuratau Range. P.N.Podkopaev, 1959 (382, table 5; 166, p. 189). Stratotype in the "Central" section of the Uchkulach mine in Khanbandytau.

Synonym: Uchkulach Suite, Учкулачская св.

Lithology and Thickness

Divided into two subsuites.

Upper - Dolomites and dolomitic limestones. Thickness 250-300m.

Lower - Limestones, dolomites, claystone (argillites), siltstone (aleurolites), sandstones, gravels, conglomerates. Thickness 50-300m.

Lithology Pattern:

Dolomitic limestone

Relationships and Distribution

Lower contact

Transgressively overlies the Band Fm in Khanbandytau. In Pistalitau, the nature of the contact with the underlying Chimgurgan Fm is unclear

Upper contact

It is conformably overlain by the Khanbandytau Fm. In Pistalitau, the nature of the contact with the overlying Pistalitau Fm it is conformable.

Regional extent

Northern foothills of the North Nuratau Range, Khanbandytau and Pistalitau Mountains.

GeoJSON

null

Fossils

Age

Early Givetian. P.N.Podkopaev et al. (1961f.) called it the Upper Uchkulach suite. Its stratigraphic position was most accurately determined in 1953 by O.I.Sergun'kov (1954f.), and later by K.A.Nabiev (1960f.), V.P.Vashchenko et al. (1980f.). In the literature (165; 457) it is known as the Upper Uchkulach suite. In the Strat. sl. (441) this part of the section is also described as the Upper Uchkulach suite, with the note that the name of the term contradicts the rules of stratigraphic nomenclature. A.I. Kim (165) considers that the lower part of the Uchkulach Fm represents a lateral equivalent of the Lower Uchkulach Subformation. On the 1:500,000 State Geological Map of Uzbekistan (460), it is assigned to the Upper Subformation of the Uchkulach Fm.

Age Span:

Beginning stage:

Eifelian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

394.30

Ending stage:

Eifelian

Fraction up in the ending stage:

0.75

Ending date (Ma):

387.55

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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