Chakpaktas Fm
Period:
Paleocene
Age Interval:
middle Eocene (early Lutetian)
Province:
Zaisan (Zaysan) Basin - East
Type Locality and Naming
Synonym: E2chk
Lithology and Thickness
Upper unit is 21.5 m of Variegated clays (yellowish-brown, red, gray, greenish), with rare interlayers of variously grained sands. At the top, brownish-red siltstones with interlayers of fine- and medium-grained sands. In the upper part of the clayey thickness - bone fragments. Lower unit is 7.5 m of Quartz pebbles with a mixture of variously grained sand, interbedded with white quartz sands.
Lithology Pattern:
Coarse-grained sandstone
Relationships and Distribution
Lower contact
Major unconformity. Overlies Paleozoic formations (maybe Permian-age Akkolan Fm ?)
Upper contact
Unconformably overlain by the Obailyn Fm
Regional extent
GeoJSON
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Fossils
Age
middle Eocene (early Lutetian); top is a minor hiatus of uncertain extent (not included in age span here); major unconformity below (onto Paleozoic)
Age Span:
Beginning stage:
Lutetian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
48.07
Ending stage:
Lutetian
Fraction up in the ending stage:
0.5
Ending date (Ma):
44.55
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Information provided by Nariman Jamikeshev from Kazakh-language sources and from other publications.