Ergozin Formation

Ergozin Fm

Period:

Triassic

Age Interval:

Rhaetian, U3

Province:
Ustyurt-Sultanuzdag

Type Locality and Naming

Along the Ergizi hillock, Ustyurt. A. M. Akramkhodzhaev, S. S. Aykhodzhaev, K. A. Alimov, E. I. Safonov, 1970 (46, p. 29). The type section was proposed by V. N. Polyakov et al. in 1972 at the Shakhpakhty plateau.

Synonym: Ergozinskaya Suite, Эргозинская св.

Lithology and Thickness

Boreholes in the Ustyurt, Takhatakir Ridge. In the lower part, light-gray sandstones (up to 40m), above - gray clays, siltstone (aleurolites), argillites with plant detritus. Thickness 65-799m.

Lithology Pattern:

Sandy_claystone

Relationships and Distribution

Lower contact

The basal layers of the suite lie with angular unconformity or transgressively on Permian-Triassic or older formations.

Upper contact

The suite is overlain with erosion by the Tahtakir Fm.

Regional extent

The suite is included in the Sandzhar Horizon (252) and corresponds to the Kuanysh (K1 and K2) or X and XI commercial horizons. Facies analogs are the Changis Fm, Sandzhar Fm, and Kokalinsk Fm.

GeoJSON

null

Fossils

Contains a complex of spores and pollen - Cythidites minor Couper (22), Toroisporis solutionis Kr., Klukisporis variegatus Couper (1), Camptotriletes anogrammiens K.-M., Converrucosisporites mioroverrucosus Couper., Ginkgocycadophitus (5), Disaccites (3), Caytonipollenites sp. (1), Classopollis sp. (62), Quadraeculina sp. (383, Table 4, p.1),

Age

Complex of spores and pollen do not contradict the Early Jurassic. Dated to the Late Triassic (?) - Early Jurassic (165). Some authors date the suite to the Early - Middle (?) Jurassic (383, Table 5; 446).

Age Span:

Beginning stage:

Rhaetian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

205.74

Ending stage:

Pleinsbachian

Fraction up in the ending stage:

1.0

Ending date (Ma):