Dzheltumsuk Formation

Dzheltumsuk Fm

Period:

Carboniferous

Age Interval:

upper Moscovian, K4

Province:
Kyzylkum Region

Type Locality and Naming

Over the Dzheltumsuk ridge, Taktatau Mountains, Central Kyzylkum. 3.S.Rumyantseva, 1974 (386, pp. 31-34).

Synonym: Dzheltumsukskaya Formation, Джелтумсукская св.

Lithology and Thickness

Central Kyzylkum, central part of the Taktatau Mountains.

Divided into two parts:

Upper – Silty (aleuritic)-limestone - rhythmic interbedding of sandstones, siltstone (Aleurites), oolitic, detrital and algal-foraminiferal limestones. Thickness 620m.

Lower - sandy-silty (aleuritic) – siltstones (Aleurites), interbedded with sandstones, sandy limestones, rare layers of conglomerates, gravelites. Thickness 360m.

Lithology Pattern:

Siltstone

Relationships and Distribution

Lower contact

It lies conformably on the Oguz Fm

Upper contact

It is overlain conformably by the Bassay Fm. Corresponds to the middle sub-suite of the Tachtatau Fm (165; 386; 439).

Regional extent

GeoJSON

null

Fossils

Upper – Contains foraminifera - Fusulina kamensis Saf., F. schellwieni Staff., F. pseudoelegans Chern., Pseudostaffella umbilicata Putrja et Leont., P. rostovzevi Raus., Hemifusulina pseudobocki (Putrja et Leont.), H. cf. subrhomboides Raus. and others; brachiopods - Choristites mosquensis Fisch., Derbyia regularis Waag. and others, pelecypods - Modiolopsis teplovi Vern., Schizodus whelleri Swal. and others; gastropods - Bellerophon crasus Meek. et Worth., Retispira globularis (Netsch.) and others; plant remains - Lepidodendron kirghizicum Zal., L. sp. (386).

Lower – Contains foraminifera - Eostaffella acutissima Kir., Schubertella lata Lee et Chen, Pseudostaffella syzranica Raus. et Saf., Hemifusulina paraelliptica Raus., Fusulina shellwieni Staff., F. pseudoelegans Chern., F. kamensis Saf.; brachiopods - Choristites priscus Eischw., Derbyia regularis Waag. and others; plant remains Lepidodendron kirghizicum Zal.

Age

The listed fauna complex is characteristic of the Aterek Horizon deposits. Plant remains have a wide vertical distribution, occurring in the middle and in the Carboniferous, gastropods are known from the Moscovian horizon.

Age Span:

Beginning stage:

Moscovian

Fraction up in beginning stage:

0.65

Beginning date (Ma):

309.87

Ending stage:

Moscovian

Fraction up in the ending stage:

1.0

Ending date (Ma):

307.02

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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