Cenozoic

Cretaceous

Jurassic

Triassic

Permian

Carboniferous

Devonian

Silurian

Ordovician

Cambrian

Neoproterozoic

Main source = Baratov, R.B., et al. (1976). Subdivisions of stratified and intrusive rocks of Tajikistan. Publishing House "Donish", Dushanbe, 269 pp. plus tables. Provided by Dr. Jovid Aminov, Nazarbayev University, Astana, Kazakhstan Translated to English by the GeoGPT group, Zhejiang Lab, Hangzhou, China--see About

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Dzhizhikrut Formation

Dzhizhikrut Fm

Period:

Jurassic

Age Interval:

Bathonian, S4

Province:
North Tajik

Type Locality and Naming

Synonym: Dzhizhikrutskaya suite, Джижикрутская свита

Reference section:

Lithology and Thickness

It has a cyclic structure and consists of alternating quartz sandstones from coarse to fine-grained varieties, siltstones, clays, and carbonaceous rocks with numerous coal seams. The sorting of the terrigenous material in the rocks is satisfactory. The bedding in the sandstones ranges from large-scale diagonal and unidirectional cross-bedding to small-scale bidirectional. The thickness of the suite is 400-700 m.

Lithology Pattern:

Sandy_claystone

Relationships and Distribution

Lower contact

The considered deposits lie either sharply unconformably on the rocks of the Paleozoic, or with a slight erosion on the formations of the Ravat Fm, previously attributed to the Upper Triassic deposits, and according to our and R.Z. Gengkina's data, included in the Lower Triassic section.

Upper contact

The Jurassic stratum is overlain by Cretaceous red beds with an unclear contact.

Regional extent

In the valleys of the rivers Fandarya, Pasrud, Yagnob, the section of the coal-bearing Lower-Middle Jurassic deposits - J₁₊₂is subdivided into a number of suites identified by T.A. Sixtel (Decisions..., 1959): Fand, Kukhiraat, Gabirut, Dzhizhikrut, Kukhimalek.

GeoJSON

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Fossils

In the considered layer, a representative complex of plant remains has been identified, in which there is an abundance and diversity of the genus Coniopteris ferns, less frequently Cladophlebis, Eboracia, Nilssonia (N. compta, N. serrata, N. polymorpha, N. dentata, N. acuminata) are widely represented, Ptilophyllum, large horsetails Equisetum beanii, Ginkgo species of the genus Sphenobaiera.

Age

The complex indicates the Bathonian age of the enclosing flora rocks.

Age Span:

Beginning stage:

Bathonian

Fraction up in beginning stage:

0.4

Beginning date (Ma):

167.02

Ending stage:

Bathonian

Fraction up in the ending stage:

0.8

Ending date (Ma):

165.87

Depositional setting

Depositional pattern:

Additional Information

Compiler:

Extracted from Baratov, R. B. (1976). Subdivisions of stratified and intrusive rocks of Tajikistan. Donish, Dushanbe, 276.