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

Chaltash Formation

Chaltash Fm

Period:

Silurian

Age Interval:

Ludlovian-Prídolian, N2

Province:
Nuratau

Type Locality and Naming

Along the Chaltash River, southern slope of Mount Merishkor, N. Nuratau Range. I.A. Kim et al., 1987 (165, p.48).

Synonym: Chaltash Suite, Чалташская св.

Lithology and Thickness

The Chaltash Fm is subdivided into a lower Shalyn Beds Fm and an upper Chashmazrak Beds Fm. Detrital, massive, light limestones with interlayers containing sandy and gravelly quartz grains and a clayey material admixture. At the base, interlayers of limestone-terrigenous rocks. In the upper part, stromatolitic, algal, detrital light-gray limestones. Thickness 235m.

Lithology Pattern:

Limestone

Relationships and Distribution

Lower contact

Conformably overlies the Abartkan Beds Fm of the Khatinbulak Fm

Upper contact

It is overlain by the Dzhalpak Fm.

Regional extent

GeoJSON

null

Fossils

Contains stromatoporoids - Ecclimadictyon quasifastigiatum Bogojav.; tabulates Squameofavosites isfaraensis Chekh., Emmonsiella ex gr. saaminica (Chekh.); rugosans Zelophyllum conicum Bulw., Mukophyllum crateroides Ether., Kodonophyllum truncatum (Linn.), Fasciphyllum kokshalicum Pavl.; brachiopods - Gypidula ex gr. pelagica Barr., G. incipiens Barr., Lanceomionia tarda Barr., Atrypopsis megaerella (Plod.), Atrypoidea linguata columbella Barr., Protathyris praecursor Kozk., Retziella weberi Nikif., Tadschikia wilsoniaformis Nikif., Nikiforovaena lynxoides (Nal.), N. isfarensis Nikif., N. favositicus Nikif., Spinatrypa pseudosquamosa Nikif., Alaskospira dunbari K. et Ams.; conodonts - Ozarcodina crispa (Wall.).

Age

Assigned to the Ludlov-Pridoli of the upper Silurian. (165; 460).

Age Span:

Beginning stage:

Ludfordian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

425.01

Ending stage:

Pridoli

Fraction up in the ending stage:

1.0

Ending date (Ma):

419.00

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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