Karachatal Fm
Period:
Silurian
Age Interval:
Ludlovian, N7
Province:
Nuratau
Type Locality and Naming
By the river Karachatal, Karachatau Mountains, South Nuratau Ridge. Yu.I. Loskin et al., 1963 (271, pp. 41-43). Stratotype by the Karachatal River.
Synonym: Karachatalskaya Suite, Карачатальская св.
Lithology and Thickness
Polymictic siltstone (aleurolites), sandstones, gravellites, fine-pebble conglomerates, in the upper part, clay slates predominate. Thickness 180-250 m.
Lithology Pattern:
Siltstone
Relationships and Distribution
Lower contact
Lower boundary with Naukatsay Formation, normally stratigraphic
Upper contact
Upper boundary unknown (165; 371; 443; 460).
Regional extent
South Nuratau Ridge, watershed part of the Karachatau Mountains, from the village of Tusun on the west to the village of Ramazan on the east; small outcrops on the northern slope of the Gobduntau Mountains (Shumakov et al., 1984).
GeoJSON
null
Fossils
Age
Ludlovian age by graptolites - Bohemograptus cf. bohemicus (Barr.), Colonograptus colonus (Barr.), Saetograptus chimaera (Barr.), Lobograptus crinitus (Wood.), Plectograptus aff. macilentus (Törnq.), Neodiversograptus nilssoni(Lapw.).
Age Span:
Beginning stage:
Gorstian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
426.74
Ending stage:
Ludfordian
Fraction up in the ending stage:
1.0
Ending date (Ma):
422.73
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Z.M. Abduazimova – In: GeoGPT translation of: “Abduazimova, Z.M. (Ed.), 2001. Stratigraphic Dictionary of Uzbekistan. IMR (Institute of Mineral Resources), Tashkent, 580 pp. (In Russian)”