Yalovach Formation

Yalovach Fm

Period:

Cretaceous

Age Interval:

Turonian – Santonian, F3, F6, F9, F9e

Province:
Fergana

Type Locality and Naming

Along the Yalovach River, Eastern Fergana. O.S. Vyalov, 1937 (426, p. 123, 129). Upper formation in Varzyk Gr

Synonym: Yalovach Suite, Яловачская св.

Lithology and Thickness

In the lower part - pink sands, sandstones, gravelites with clay layers; middle - red clays with gravelite and sandstone layers; upper - light gray, red sandstones, gravelites. Thickness 10-310m.

Lithology Pattern:

Clayey sandstone

Relationships and Distribution

Lower contact

Conformably overlies the Urumbash Fm, with erosion on the oyster bed or transgressively on the Paleozoic

Upper contact

Conformably overlain in S. Fergana – Nichkesay Fm, in S. and W. Fergana – Palvantash Fm, in E. Fergana - with erosion of the Agaaral Fm, in E. Fergana – Kugat Fm

Regional extent

Central, Southern, Western, and Eastern Fergana, Kuramin Range

GeoJSON

null

Fossils

Contains freshwater bivalve mollusks Sainshandia aralica Mart., Neotrigonioides gigantus Mart., Pseudohyria triangularis Mart., dinosaur bone fragments, turtle and crocodile shields in the upper part.

Age

Conditionally assigned to the middle Turonian - Santonian; Along O.S. Vyalov, to the upper Turonian.

Age Span:

Beginning stage:

Turonian

Fraction up in beginning stage:

0.5

Beginning date (Ma):

91.65

Ending stage:

Santonian

Fraction up in the ending stage:

1.0

Ending date (Ma):

83.65

Depositional setting

Depositional pattern:

Additional Information

Compiler:

I.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)"