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

Roch Formation

Roch Fm

Period:

Silurian, Devonian

Age Interval:

Upper Silurian-Lower Devonian, Z3

Province:
Zarafshan-N.Gissar

Type Locality and Naming

Along the village of Roch, Chumkartau Mountains. D.A. Starshinin et al. (1994) from the composition of the Chumkartau suite (460, p. 96).

Synonym: Rochskaya Suite, Рочская св.

Lithology and Thickness

Claystone (argillites), siltstone (aleurolites) with interlayers of sandstones, gravelites, conglomerates, in the upper part, clayey and sandy limestones predominate. Thickness more than 100 m.

Lithology Pattern:

Sandy limestone

Relationships and Distribution

Lower contact

With erosion and conglomerates at the base, it lies on the slates of the Garibak Fm

Upper contact

It is conformably overlain by the dolomites of the Shingak Fm (460).

Regional extent

Chumkartau Mountains, Zarafshan River valley.

GeoJSON

null

Fossils

Contains corals - Favosites lazutkini Tchern., Sqvameofavosites tchortangensis Chekh., Siringopora ferganensis Fom., Gyalophyllum angelini Wdkd., Rhizophyllum gotlandicum Roemer., Mycophyllum crateroides Ether.; brachiopods - Lissatrypa columbella (Barr.) and others

Age

Fossil data determines the age of the enclosing rocks as late Silurian-early Devonian (Starshinin et al., 1994).

Age Span:

Beginning stage:

Pridoli

Fraction up in beginning stage:

0.75

Beginning date (Ma):

419.93

Ending stage:

Lochkovian

Fraction up in the ending stage:

1.0

Ending date (Ma):

412.40

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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