Dzhurgantau Formation

Dzhurgantau Fm

Period:

Proterozoic

Age Interval:

Lower Proterozoic (?), K5

Province:
Kyzylkum Region

Type Locality and Naming

Along the Dzhurgantau structure, Central Kyzylkum. P.N. Podkopaev et al. in 1965 (1966) attributed it to the Ordovician (?).

Synonym: Dzhurgantau Suite, Джургантауская св.

Lithology and Thickness

Gray-green, light and dark green amphibolites, amphibole, garnet-biotite, garnet-cordierite-orthoclase, cordierite-orthoclase, cordierite-sillimanite-biotite, biotite-quartz, epidote-albite, albite-chlorite-actinolite crystalline schists, biotite quartzites. The rocks are characterized by the complete absence of primary stratification and the widespread development of secondary textures. Thickness 300-600 m.

Lithology Pattern:

Gneiss

Relationships and Distribution

Lower contact

Stratigraphic boundaries are not established.

Upper contact

Regional extent

Central Kyzylkum, Southern Tamdytau, Tas-Kazgan area.

GeoJSON

null

Fossils

Organic remains are absent.

Age

According to Z.M. Abdazimova (7; 9; 16; 17), objects from gneisses and crystalline rocks of the suite, attributed to chitinozoa, are abiogenic features and cannot date the age of the rocks of the Dzgyrgabtay Fm.The age is determined based on radiometric data from samples of granitic gneisses that have undergone polymetamorphism: from zircons, 1750 ± 80 million years (Khokhlov et al., 1987f.); 1079 million years – K–Ar method (66; 67); 1080 million years (isochron method, 4 samples of granitic gneisses, Pb–Zn, Khokhlov, Golovin et al., 1991f.). V.A. Kokhlov (493) considered the D. suite to be Lower-Middle Proterozoic; Sh.Sh. Sabdyushov et al. (1983) - Middle Riphean; A.K. Bukharin et al. (122) include it in the composition of the Lower Taskazgan Fm sub-suite and date it to the Cambrian-Early Ordovician based on the finds of chitinozoa. In the monograph (165) and on the State Geological Map-500 of Uzbekistan (460), the suite is conditionally attributed to the Lower Proterozoic.

Age Span:

Beginning stage:

Statherian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

1,800.00

Ending stage:

Statherian

Fraction up in the ending stage:

1.0

Ending date (Ma):

1,600.00

Depositional setting

Depositional pattern:

Additional Information

Compiler:

R.N. Abdullaev, 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)”