Uchkuduk-Cret Formation

Uchkuduk-Cret Fm

Period:

Cretaceous

Age Interval:

upper Cenomanian, K1-K5, K7, K9

Province:
Kyzylkum Region

Type Locality and Naming

Along the Uchkuduk well, Central Kyzylkum. I.M. Abdazimova, 1988 (24, pp.65-66), used the name proposed by E.M. Shmarovich et al. (322; 446) for the Uchkuduk Mountains. On plains, it is exposed by wells. Stratotype in the southwestern foothills of Altyntau.

Synonym: Uchkuduk Suite, Учкудукская св.

Lithology and Thickness

Coastal-marine greenish-gray, brown sandstones, gravels, conglomerates with layers of clays and siltstone (aleurolites). Thickness 5-45m.

Lithology Pattern:

Coarse-grained sandstone

Relationships and Distribution

Lower contact

Overlies the Paleozoic, Donguztau Fm, and Uru Fm with erosion or transgressively

Upper contact

Overlain by the Dzhayrantuy Fm with erosion.

Regional extent

Central Kyzylkum, foothills of Kuldzhuktau, Auminzatau, Bukantau, Tamdytau, Altyntau, Nuratau Mountains. Correlated with the larger part of the Gazdagan Fm of South Gissar.

GeoJSON

null

Fossils

Contains marine bivalve mollusks - Korobkovitrigonia darwaseana Rom.; foraminifers - Paragaudryina inornata Suleim., Gaudryinopsis asiaticus (N. Byk.); complex of spores and pollen - Foveosporites cenomanicus (Chl.) Shv. (1-2), Selaginella ferganica Fok. (1-2), Taurocusporites reduncus (Bolch.) Stov. (8-10), Stenozonotriletes radiatus Chl. (1-2), Tricolpites sp. (5-30).

Age

Belongs to the upper Cenomanian, in the Strat. Sl. (446) - to the lower part of the lower Turonian.

Age Span:

Beginning stage:

Cenomanian

Fraction up in beginning stage:

0.5

Beginning date (Ma):

97.20

Ending stage:

Cenomanian

Fraction up in the ending stage:

0.95

Ending date (Ma):

94.23

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)”