Keriz Formation

Keriz Fm

Period:

Carboniferous

Age Interval:

Upper Moscovian, K3

Province:
Kyzylkum Region

Type Locality and Naming

Along the village of Keriz, Bukantau Mountains, Central Kyzylkum. 3. S. Rumyantseva et al., 1973, named by A.A. Shapkin et al. (1974).

Synonym:

Lithology and Thickness

Carbonaceous-siliceous, siliceous-carbonate, clayey, calcareous-clayey slates, interbedded with siltstone (aleurolites), sandstones, gravelites, containing rare lenses and interlayers of conglomerates and detrital limestones. Thickness about 380m.

Lithology Pattern:

Siliceous limestone

Relationships and Distribution

Lower contact

Except for the Okzhetpes Mountains, contacts with surrounding deposits are tectonic. In the Okzhetpes Mountains, according to A.A. Shapkin et al. (1974), a gradual transition from the limestones of the Auliekuduk Fm to the calcareous sandstones of the Keriz Fm

Upper contact

Except for the Okzhetpes Mountains, contacts with surrounding deposits are tectonic. In the Okzhetpes Mountains, according to A.A. Shapkin et al. (1974), an unconformable overlap of the latter by the Sardar Fm is established.

Regional extent

Central Kyzylkum, Okzhetpes Mountains, Boztau, Kokpatas. Stratotype 3 km east of the village of Keriz. Yu.S. Savchuk et al. (1987), P.A. Mukhin et al. (1988) refer the Kerzis Fm to the flysch-olistostromal formation of the middle Carboniferous.

GeoJSON

null

Fossils

In the pebbles of limestones, late Bashkirian and early Moscovian foraminifers, Carboniferous brachiopods, and trilobites.

Age

Along its position in the section, a late Moscovian age is accepted. (460).

Age Span:

Beginning stage:

Moscovian

Fraction up in beginning stage:

0.5

Beginning date (Ma):

311.09

Ending stage:

Moscovian

Fraction up in the ending stage:

1.0

Ending date (Ma):

307.02

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)”