Akansai Fm
Period:
Carboniferous
Age Interval:
early and middle Late Carboniferous
Province:
Zaisan (Zaysan) Basin - East, Zaisan (Zaysan) Basin - Central
Type Locality and Naming
Synonym: Akansaiskaya; C3ak
Lithology and Thickness
Ca. 130 m of Coaly claystone, sandstone, tuffaceous sandstone, gritstone and basalt.
Lithology Pattern:
Sandy claystone
Relationships and Distribution
Lower contact
Unconformable onto the Kaigenbulak Fm
Upper contact
Overlain by the Kenderlyk Fm (Kenerlyk Fm)
Regional extent
Originally throughout the entire basin; but later tectonics and erosion during uplifts implies that the main surface exposures of the Late Carboniferous-Permian succession is a 2-km-thick succession in the Kenderlyk Trough in the southern part of the Zaisan (Zaysan) basin (Nurbekova et al., 2023).
GeoJSON
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Fossils
Age
early and middle Late Carboniferous (Bashkirian-Kasimovian?)
Age Span:
Beginning stage:
Bashkirian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
323.40
Ending stage:
Kasimovian
Fraction up in the ending stage:
1.0
Ending date (Ma):
303.68
Depositional setting
Depositional pattern:
Additional Information
Rock porosity does not exceed 7-10%. No rocks are noted in the suite with any oil shows or gas indications.
Compiler:
Information provided by Nariman Jamikeshev from Kazakh-language sources and from other publications (e.g., Nurbekova et al., 2023. High-quality source rocks in an unexplored basin: The upper Carboniferous-Permian succession in the Zaysan Basin (Kazakhstan). Internat. Jour. Coal Geology, 272, article 104264.