Aytym-Cret Formation

Aytym-Cret Fm

Period:

Cretaceous

Age Interval:

Santonian, K1-K9

Province:
Kyzylkum Region

Type Locality and Naming

Named after the village of Aytym, Central Kyzylkum I. M. Abdurazimova, 1998 (165, p. 144). The name proposed by A.I. Pak (1959) for the Aitym horizon was used. The stratotype is located 700 m northeast of the Tamdy-truba well, on the southwestern plunge of the Bukantau Mountains.

Synonym: Aytym Suite, Айтымская св.

Lithology and Thickness

Nearshore-marine sandstones, sands, and clays—yellow, gray, greenish-gray, and dark brown—with lenses of sandy coquina. Thickness: 22–56 m.

Lithology Pattern:

Clayey sandstone

Relationships and Distribution

Lower contact

It lies with an erosional unconformity on the Bissektin Fm

Upper contact

It is overlain, also with an erosional unconformity, by the Karakatin Fm and Upper Paleocene deposits.

Regional extent

In the central Kyzylkum, the foothills of Bukantau, and on the adjacent plains, it is penetrated by boreholes.

GeoJSON

null

Fossils

Contains ammonites Stantonoceras sp.; marine bivalve mollusks Ostrea itemiriensis Vinok., Fatina akkaptschigensis Bobk., Exogyra dzharanensis Vinok., Korobkovitrigonia akkaptschigensis Beliak., Linotrigonia syrdariensis (Arkh.); foraminifera Gaudryinella pseudoasiatica N. Byk.; a spore and pollen assemblage (%): Stenozonotriletes radiatus Chl. (1), Gnetaceapollenites evidens (Bolch.) Verb. (11), Kuprianipollis santaloides (Stelm.) Kom. (7), K. elegans (Zak.) Kom. (1), Proteacidites sp. (1.5); numerous bones of armored and predatory dinosaurs, fragments of turtle shells, and crocodile teeth.

Age

It is assigned to the Santonian.

Age Span:

Beginning stage:

Santonian

Fraction up in beginning stage:

0.15

Beginning date (Ma):

85.39

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