Kyzylnur Fm
Period:
Permian, Triassic
Age Interval:
Wuchiapingian – Induan, CK2
Province:
Chatkal-Kuramin Region
Type Locality and Naming
Kyzylnura village, southwestern spurs of the Chatkal Range. N.P. Vasilykovsky, 1952 (131, p. 229).
Synonym: Kyzylnurinskaya Suite, Кызылнуринская св.
Lithology and Thickness
Tuffs, ignimbrites, less frequently lavas of trachyriolites, rhyolites, rhyodacites, and trachyriodacites, lenses of black obsidian, at the base sometimes conglomerates, sandstones, and siltstone (aleurolites). Thickness 65-750m.
Lithology Pattern:
Volcanic_ash
Relationships and Distribution
Lower contact
Lies unconformably on the Shurabsay Fm and beyond the borders of Uzbekistan on the Ravash Fm
Upper contact
Overlain by the Jurassic coal-bearing formation.
Regional extent
GeoJSON
null
Fossils
Contains plant remains - Schizoneura sp., Pseudovoltzia liebeana (Gein.), Angrenia angustifolia Sixt.
Age
The age of the formation is accepted as Permian-Early Triassic. The age of the formation is controversial due to the discrepancy between radiological and paleobotanical dating. Some researchers, based on isotopic age data of 272 pm 10 million years (70; 465) and 278 pm 8 million years (380) of volcanic and subvolcanic formations of the formation, refer it to the upper part of the Lower Permian. Others, based on flora determinations, consider it Permian-Triassic (450). The basis for this is the findings of the species Pseudovoltzia liebeana, characteristic of the Late Permian, as well as the Mesozoic genus Schizoneura sp. On the State Geolmap-500 of Uzbekistan (460) it is referred to the Lower Permian, in the Strat. sl. (443) - to the Upper Permian.
Age Span:
Beginning stage:
Wuchiapingian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
259.55
Ending stage:
Induan
Fraction up in the ending stage:
1.0
Ending date (Ma):
249.88
Depositional setting
Depositional pattern:
Additional Information
Compiler:
V.V. Mikhailov, T.A. Iskandarkhojaev – In: GeoGPT translation of: “Abduazimova, Z.M. (Ed.), 2001. Stratigraphic Dictionary of Uzbekistan. IMR (Institute of Mineral Resources), Tashkent, 580 pp. (In Russian)”