Kurgantau Formation

Kurgantau Fm

Period:

Cambrian

Age Interval:

Vendian-Lower Cambrian (?), K5

Province:
Kyzylkum Region

Type Locality and Naming

Along Mt. Kurgantau, S. Tamdytau, C. Kyzylkum.

Identified in May 1991, Along the recommendation of the Stratigraphy and Geological Map Commission of the Kyzylkum Geodynamic Polygon from the composition of the Besapan Fm (Abduazimova et al., 1993). It corresponds to the lower sub-suite of the Besapan Fm (9, pp.3-14). The new name is given in connection with the establishment of two genetically different types of sections in the deposits attributed to the Besapan Fm. Stratotype in the area of Mt. Kurgantau.

Synonym: Kurgantau Suite, Кургантауская св.

Lithology and Thickness

Gray, dark-gray, carbonaceous-biotite-chlorite-quartz, carbonaceous-carbonate-mica-quartz, carbonaceous-mica slates, for which the development of secondary textures is characteristic. Thickness (visible) 980-1000 m}, taking into account the flaky-folded tectonics no more than 450-500 m.

Lithology Pattern:

Claystone

Relationships and Distribution

Lower contact

Reliable stratigraphic contacts are unknown.

Upper contact

Everywhere the rocks of the suite are in contact with the surrounding deposits along discontinuous faults.

Regional extent

Central Kyzylkum, Southern Tamdytau, area of the city of Kurgantau, southern and western flanks of the Djurgantau, south of Mt. Besapanta, revealed by the deep Muruntau borehole SG-10 in the interval 1300-2360m and in Auminza-Beltau.

GeoJSON

null

Fossils

Age

The Vendian-Early Cambrian age is established conditionally by the position in the section above the Riphean deposits and by comparison with analogs in Bukantau - Khodzhaahmet suite, in S. Nuratau - with the Kansai suite. A.K. Bukharin et al. (122) attributed these formations to the lower sub-suite of the Tashtagan Fm of the middle-late Ordovician; A.V. Tolokonnikov et al. (1984) - to the lower sub-suite of the Besapan Fm of the middle-late Ordovician, M. (visible) 300-2000m; P.A. Mukhin et al. (317) - to the lower sub-suite of the Besapan Fm conditionally middle Cambrian-middle Ordovician; Ya.B. Aysanov et al. (1986) on the geological map of C. Kyzylkum date these formations to the Vendian; the authors of the geological map of the Kyzylkum Geodynamic Polygon (Savchuk et al., 1993) distinguish these meta-terrigenous formations in the Kurgantau Fm and conditionally attribute it to the Vendian-Lower Cambrian, in the monograph (165) it is conditionally attributed to the Vendian; on the State GeolMap-500 of Uzbekistan (460) - conditionally to the Vendian-Lower Cambrian.

Age Span:

Beginning stage:

Ediacaran

Fraction up in beginning stage:

0.0

Beginning date (Ma):

635.00

Ending stage:

Fortunian

Fraction up in the ending stage:

1.0

Ending date (Ma):

529.00

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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