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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Aylok Formation

Aylok Fm

Period:

Silurian

Age Interval:

middle Llandovery-Wenlock (S₁), C1b

Province:
Central W Tajik

Type Locality and Naming

Sections of the Dukdon type extend along the foot of the Dukdon ridge and are represented by the Aylok thickness.

Synonym: Aylok thickness

Reference section:

Lithology and Thickness

210 m thick, is made up of gray, locally brecciated limestones.

Lithology Pattern:

Limestone

Relationships and Distribution

Lower contact

Kutal Fm

Upper contact

This thickness is followed by Ludlow-Pragian stage deposits (Lavrushevich et al., 1973b).

Regional extent

They are widespread in the Zarafshan-Gissar region.

GeoJSON

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Fossils

with remains of Llandovery-Wenlock stromatoporoids, tabulate corals Favosites favosus Goldf., Multisolenia tortuosa Fritz, Palaeofavosites diversospinus Lel.; rugose corals Pseudophaulactis lykophylloides Zapr. et Ivnsk., Zelophyllum cylindricum (Ivnsk.), Schlotheimophyllum patellatum (Schlotheim), Holacanthia flexuosum (Linn.); brachiopod Pentamerus ex gr. oblongus Sow.

Age

The fossil assemblage shows it is Llandovery-Wenlock

Age Span:

Beginning stage:

Aeronian

Fraction up in beginning stage:

0.5

Beginning date (Ma):

439.54

Ending stage:

Homerian

Fraction up in the ending stage:

1.0

Ending date (Ma):

426.74

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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