Zaisan Fm
Period:
Neogene
Age Interval:
mid-Miocene
Province:
Zaisan (Zaysan) Basin - East
Type Locality and Naming
Synonym: Zaysan Fm, N1zs
Lithology and Thickness
25.2 m of Green and greenish-brown clays, montmorillonitic and hydromica, with very rare interlayers of greenish-gray siltstones, locally gypsiferous, with inclusions of calcareous concretions and small nodules of iron and manganese hydroxides.
Lithology Pattern:
Gypsiferous claystone
Relationships and Distribution
Lower contact
Unconformable onto the Jamangarin Fm
Upper contact
Unconformably overlain by the Sarybulak Fm
Regional extent
GeoJSON
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Fossils
Age
mid-Miocene (Langhian); bound by minor hiatuses of uncertain extent (not included in age span here)
Age Span:
Beginning stage:
Langhian
Fraction up in beginning stage:
0.25
Beginning date (Ma):
15.45
Ending stage:
Langhian
Fraction up in the ending stage:
1.0
Ending date (Ma):
13.82
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Information provided by Nariman Jamikeshev from Kazakh-language sources and from other publications.