Cenozoic

Cretaceous

Jurassic

Triassic

Permian

Carboniferous

Devonian

Silurian

Ordovician

Cambrian

Neoproterozoic

Main source = Baratov, R.B., et al. (1976). Subdivisions of stratified and intrusive rocks of Tajikistan. Publishing House "Donish", Dushanbe, 269 pp. plus tables. Provided by Dr. Jovid Aminov, Nazarbayev University, Astana, Kazakhstan Translated to English by the GeoGPT group, Zhejiang Lab, Hangzhou, China--see About

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Yakkarchin Formation

Yakkarchin Fm

Period:

Carboniferous

Age Interval:

middle - bottom of the upper Visean (C v₂-m₁), C1, C1a, C1b, C1c

Province:
Central W Tajik

Type Locality and Naming

Includes in Hisar-Zarafshan ranges, and Obisafit, Turkparidin, Chakykalya typesections. It is distinguished and detailed by V. D. Saltovskaya (1965; 1966; 1974).

Synonym: Yakkarchin suite, Якарчинская свита

Reference section:

Lithology and Thickness

It is distinguished at the base are sandstones, conglomerates, shales; above - dark carbonaceous clayey limestones.

Lithology Pattern:

Sandy_claystone

Relationships and Distribution

Lower contact

The rocks without visible unconformity (valley of the Zidddy river) lie on the sandy-shale deposits of the Tournaisian-lower Visean? Marguzor Fm (маргуэорской свиты)

Upper contact

It is conformably covered by the upper Visean Sangalt Fm. (сангальтской свитой)

Regional extent

They are widespread in the Turkestan, Zarafshan-Gissar, and Karategin regions.

GeoJSON

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Fossils

with remains of algae Koninckopora inflata (Kon.); foraminifera Plectogyra omphalota (Raus. et Reitl.); brachiopods Productus mirus Fred., Pr. sarsimbai Serg.; rugose Lithostrotion irregulare Fill., characteristic of the middle - bottom of the upper Visean.

Age

From the fossil data, it is represented at middle - bottom of the upper Visean for schematic stratigraphic purpose.

Age Span:

Beginning stage:

Visean

Fraction up in beginning stage:

0.3

Beginning date (Ma):

341.81

Ending stage:

Visean

Fraction up in the ending stage:

0.8

Ending date (Ma):

333.62

Depositional setting

Depositional pattern:

Additional Information

Compiler:

Extracted from Baratov, R. B. (1976). Subdivisions of stratified and intrusive rocks of Tajikistan. Donish, Dushanbe, 276.