Akzhai Fm
Period:
Triassic
Age Interval:
Middle to early Late Triassic
Province:
Zaisan (Zaysan) Basin - Central
Type Locality and Naming
Synonym: Akzhaiskaya, T2-3ak
Lithology and Thickness
Ca. 500 m of Rubbly, coarse-pebbled and fine-pebbled conglomerate with interbeds of gritstone and sandstone. The debris is poorly rounded and sorted. Typical constancy of rock set both in coarse waste and smaller (cementing) fractions along the whole log. Porosity of conglomerate is 20-25%. Within some intervals, bitumen evidence was marked in the orm of solid impregnation of cement, individual pellicle and crack filling.
Lithology Pattern:
Aus conglomerate
Relationships and Distribution
Lower contact
Unconformable (Early Triassic is absent) onto the Akkolka Fm (Akkolan Fm)
Upper contact
Overlain by the Tologoy Fm
Regional extent
GeoJSON
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Fossils
Age
Middle to early-Late Triassic (Anisian-Carnian?)
Age Span:
Beginning stage:
Anisian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
246.70
Ending stage:
Carnian
Fraction up in the ending stage:
1.0
Ending date (Ma):
227.30
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Information provided by Nariman Jamikeshev from Kazakh-language sources and from other publications.