Ispay Formation

Ispay Fm

Period:

Carboniferous

Age Interval:

Visean, CK3-5, CK6

Province:
Chatkal-Kuramin Region

Type Locality and Naming

Along the Ispay River, Pskem Ridge. I.M. Nigmadzhanov in 1987 (1992). Stratosky in the middle course of the Ispay River, all tributaries of the Pskem River. Lower formation in Ugam Gr.

Synonym: Ispaiskaya Suite, Испайская св.

Lithology and Thickness

Gray, thick-bedded to massive, nodular-oolitic, oolitic-algal, detrital limestones with horizons of shell limestones. Characterized by secondary dolomitization in the form of spots and lenses. Thickness 280-350m.

Lithology Pattern:

Oolitic limestone

Relationships and Distribution

Lower contact

Lies conformably on the Kibray-Carb Fm

Upper contact

It is conformably overlain by the Mashat Fm.

Regional extent

Southwestern spurs of the Tapsinsky Alatau, Ugam, Pskem, Koksui, Chatkal Ridges. Earlier, O.I. Sergun'kova (457) distinguished the deposits of the Ispay Fm in the Chatkal region under the name Itelguin Fm.

GeoJSON

null

Fossils

Contains brachiopods Gigantoproductus sarsimbaii Serg., Striatifera spinifera (Paeck.); foraminifers Endothyranopsis compressus (R. et R.), Omphalotis minima (R. et R.), Mediocris mediocris (Viss.); corals - Gangamophyllum boreale Gors., Lithostrotion volkovae Dobr.

Age

Lower Carboniferous (Upper Visean)

Age Span:

Beginning stage:

Visean

Fraction up in beginning stage:

0.6

Beginning date (Ma):

336.90

Ending stage:

Visean

Fraction up in the ending stage:

0.8

Ending date (Ma):

333.62

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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