Oshagan Fm

Period:

Paleogene

Age Interval:

early-Late Oligocene

Province:
Zaisan (Zaysan) Basin - East

Type Locality and Naming

Synonym: E3osh

Lithology and Thickness

23.1 m of Quartz sands, white, light gray, yellowish-gray, yellow with iron crusts, fine- to very fine-grained, at the base with pebble-boulder material, with interlayers of light gray and brown siltstones with iron crusts and clays with greenish, brown, and black spots.

Lithology Pattern:

Fine-grained sandstone

Relationships and Distribution

Lower contact

Unconformable onto the Buran Fm (upper Tuzkabak Gr)

Upper contact

Conformably overlain by the Nurin Fm

Regional extent

GeoJSON

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Fossils

Age

early-Late Oligocene (early Chattian); bound by minor hiatuses of uncertain extent (not included in age span here)

Age Span:

Beginning stage:

Chattian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

27.29

Ending stage:

Chattian

Fraction up in the ending stage:

0.4

Ending date (Ma):

25.59

Depositional setting

Depositional pattern:

Additional Information

Compiler:

Information provided by Nariman Jamikeshev from Kazakh-language sources and from other publications.