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

Uchkuduk-Sil Formation

Uchkuduk-Sil Fm

Period:

Silurian

Age Interval:

lower Wenlock, K9, K7

Province:
Kyzylkum Region

Type Locality and Naming

Named after the Uchkuduk collective farm, Kuldjuktau Mountains, Central Kyzylkum. Ya.B. Aysanov et al. in 1963 (42, p.23; 44, p.23-25).

Synonym: Uchkuduk Suite, Учкудукская св.

Lithology and Thickness

Essentially clayey limestones with subordinate layers of cherts, sandstones, siltstone (aleurolites), shales, and rhyolite tuffs. Thickness 50-170m.

Lithology Pattern:

Clayey limestone

Relationships and Distribution

Lower contact

Conformably overlies the Darbazin Fm west of the Tozbulak intrusion and on the southern and northern slopes of Beltau; in other places, contacts are tectonic.

Upper contact

Conformably overlain by the Dzhangel'din Fm (Dzhangeldin Fm) (165; 441;460).

Regional extent

Central and western parts of the Kuldzhuktau Mountains in the form of narrow sublatitudinal strips, often bounded by faults, predominantly on the flanks of anticlinal folds.

GeoJSON

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Fossils

Tabulates - Antheralites hemiseptopsis Lel., Favosites cf. gothlandicus Lam., F. favosiformis Sok., Halysites cf. catenularis Lin., Multisolenia frivola Klaam., Catenipora gotlandica Sok., and others; brachiopods - Eospirifer radiatus Sow., Acanthospirifer edelschteini Men., Atrypoidea cf. prunus Dalm., Eridorthis cf. reinwaldti Nikif., and others; crinoids - Megalocrinus brevis Schew., M. latebrosus Schew., Obuticrinus bullosus Yelt., Pentagonocyclicus subhelena Yelt., and others.

Age

Early Wenlock age is established by tabulates

Age Span:

Beginning stage:

Sheinwoodian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

432.93

Ending stage:

Sheinwoodian

Fraction up in the ending stage:

1.0

Ending date (Ma):

430.62

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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