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

Urtakul Formation

Urtakul Fm

Period:

Silurian

Age Interval:

Wenlock-Ludlow, N4a

Province:
Nuratau

Type Locality and Naming

Along Urtakulsay, N. Nuratau Ridge. I. A. Kim et al. (1987f.). Stratotype in the Urtakulsay basin.

Synonym: Urtakulskaya Suite, Урткульская св.

Lithology and Thickness

Upper part - organogenic-clastic massive, strongly brecciated limestones. Thickness 60-70m. To the Urtakul Fm is conditionally assigned p. conglomerate breccia. Thickness 45m.

Lower part - massive organogenic limestones. Thickness 80m.

Total thickness of formation is 180-195m.

Lithology Pattern:

Limestone

Relationships and Distribution

Lower contact

Contacts are tectonic.

Upper contact

Contacts are tectonic.

Regional extent

Northern Nuratau Ridge, in tectonic slices within the Mikhin-Daristan structure, Urtakulsay - right. component of Kyzkolsay.

GeoJSON

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Fossils

Upper part – Contains brachiopods - Conchidium ischemeticum Mal. et Sap., Leptaena rhomboidalis Linn., Atrypoidea linguata columbella (Barr.), Spirigerina supramarginalis Khalf., characteristic of early Ludlow. In fragments and cement numerous organic remains: crinoids, brachiopods, conodonts, which are known both in Wenlock and Ludlow.

Lower part – Contains brachiopods - Leptogonia depressa vulgaris H., Atrypoidea linguata columbella (Barr.), Retziella weberi Nikif., Conchidium ischmeticum Mal. et Sap. and others; trilobites - Bronteus markowski Weber, Otarion sp., Calymene ex gr. blumenbachi Brong.; tabulates - Favosites forbesi M. et H., F. adaverensis Sok., Syringopora orlovi Kim and others.

Age

A.I. Kim et al. (1970f., 1974f.), I.A. Kim, S.K. Piven (1987f.) in the composition of Fm, in addition to formations of the carbonate shallow shelf, included fragments of sections of the Kyzkolsay Fm hemipelagic formations of the remote outer shelf (Abduazimova et al., 1989f., 1996f., 11) and referred to Wenlock.

Age Span:

Beginning stage:

Homerian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

430.62

Ending stage:

Homerian

Fraction up in the ending stage:

1.0

Ending date (Ma):

426.74

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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