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

Obisafit Beds Formation

Obisafit Beds Fm

Period:

Devonian

Age Interval:

Emsian, Z1

Province:
Zarafshan-N.Gissar

Type Locality and Naming

Along the Obi-Safit River, Zarafshan Range. A.I. Kim, E.A. Elkin, M.V. Erina, R.T. Gratsianova, 1978 (470, p. 17). Stratotype in the Hodja-Kurgan sae. Previously, these deposits were distinguished by A.I. Kim and N.M. Larin (365; 368) as the conchidiella zone, and by M.A. Zhonsonskaya as the Hodjakurgan (Khodzhakurgan( beds (name reassigned) (382). M.V. Erina. Str. beds (443).

Synonym: Obi-Safit Layers, Обисафитские сл., Obi-Safit Fm; Obisafit Beds; Obi-Safit Beds; Obisafit Layers

Lithology and Thickness

Coarse-bedded, coarse-grained, locally brecciated, crinoidal, gray limestones with nodular siliceous formations, interbedded with black thin-bedded and flaggy variegated detrital, often clayey limestones with thin lenticular chert layers. Thickness 300m.

Lithology Pattern:

Siliceous limestone

Relationships and Distribution

Lower contact

Conformably overlies the Dzhaus Beds Fm

Upper contact

Overlain by the Novikhus Beds Fm (base of the costatus zone).

Regional extent

Zarafshan Ridge, Kashkadarya River basin. Correlated with the Trzhebotov Fm limestones of the Barrandien.

GeoJSON

null

Fossils

Characteristic tabulatomorph corals - Caliapora elegans Yanet., Heliolites vulgaris Tschern., Calceola sandalina Lam.; rugosans - Xystriphyllum gorskii Bulv., Werneroceras cf. crispum Barr., Zdimir pseudobaschkiricus Tschern.; brachiopods Megastrophia uralensis Vern., Sibirirhynchia alata Khod., Zeravschanotoechia zeravschanica Pzon., Punctatrypa sibirica Rzon., Uralospirifer gratsianovae Lar., Tentaculites - Nowakia richteri Bouček. et Prantl., N. holynensis Bouček.; conodonts - Polygnathus serotinus Telford., P. kimi Mashk. et Apek., crinoids Cupressocrinites gracilis Goldf.

Age

Lower Devonian

Age Span:

Beginning stage:

Emsian

Fraction up in beginning stage:

0.7

Beginning date (Ma):

399.16

Ending stage:

Emsian

Fraction up in the ending stage:

1.0

Ending date (Ma):

394.30

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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