Chavatin Formation

Chavatin Fm

Period:

Devonian

Age Interval:

Famennian, CK3, CK4, CK5

Province:
Chatkal-Kuramin Region

Type Locality and Naming

Along the Chavata stream, right tributary of the Koksu River, Chatkal Range. O.I. Sergun'kova in 1957 gave these deposits the status of a suite in the volume of the Lower Tournaisian (382, p. 55). Previously identified as the "bituminous horizon" (Ivanov et al., 1934; Krylov et al., 1940; 198).

Synonym: Chavatin Suite, Чаватинская св.

Lithology and Thickness

Fine-crystalline, banded, ribboned dolomites, sometimes with layers of organogenic limestones. Thickness 320-540m.

Lithology Pattern:

Dolomite

Relationships and Distribution

Lower contact

Along the data, it overlies the Brichmullin Fm, locally on the Kokterek Fm.

Upper contact

It is overlain with stratigraphic unconformity by the Temirbastau Fm, from which it is separated by the regional pre-Tournaisian hiatus. Along I.M. Nigmadzhanov, the Ch. suite is overlain with angular unconformity by the Akbulak-Carb-L Fm of the Lower Carboniferous.

Regional extent

Ugam, Pskem, and Chatkal Ranges.

GeoJSON

null

Fossils

Stromatoporoids - Stylostroma devonica Riab., S. stylophorum (Nich.), Dendrostroma">Dendrostroma schamgunovi Less., Anostyllostroma cf. variabile (Riab.) etc.

Age

Famennian age determined by stromatoporoids. (Shamgunov et al., 1980) and stratigraphic position in the section.

Age Span:

Beginning stage:

Famennian

Fraction up in beginning stage:

0.8

Beginning date (Ma):

361.66

Ending stage:

Famennian

Fraction up in the ending stage:

1.0

Ending date (Ma):

359.30

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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