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

Select Region(s) to search
Hold Ctrl (Windows/Linux) or Command (Mac) to select multiple

Zaamin Formation

Zaamin Fm

Period:

Devonian, Silurian

Age Interval:

Ludlow-Lockovian (S2-D1 zm), S2

Province:
North Tajik

Type Locality and Naming

It was identified in 1959 by M. M. Posokhova on the northern slopes of the Turkestan Range on the neighboring territory of Uzbekistan.

Synonym: Zaaminskaya Suite, зааминская свита

Lithology and Thickness

Dolomitic limestone. The Zaamin Fm is composed of interbedded, gray and composed of limey limestone, dolomitic limestones, clay shales, claystones, sandstones, gravelites, and conglomerates, containing interlayers of acidic effusives (quartz porphyries, felsite porphyries) and andesitic porphyrites. The incomplete thickness of the suite is 250 - 600 m.

The Zaamin Fm, заамииской свите probably includes the outcropping in the upper reaches of the river Rasraut, the nameless thickness of gray, green, and purple clay shales, claystones, sandstones, gravelites, and conglomerates with interlayers of acidic effusives and their tuffs, having an incomplete thickness of 250-400 m. Its base is unknown, it is overlain by sediments similar to the rocks of the Kyzokinskaya suite. These are here characterized by the fauna of the Kunjak and Manak horizons (Lochkov - Prague stages).

Lithology Pattern:

Dolomitic limestone

Relationships and Distribution

Lower contact

The base of the suite within the described territory is everywhere disrupted by faults, however, it is known to overlay Cambrian sediments further west in the upper reaches of the river Zaaminsu.

Upper contact

It is overlain by the Kyzykin Fm

Regional extent

Within the described area, it is spread in the Turkestanokom district on the interfluve of Altykol-Dakatsu.

GeoJSON

{"type":"Feature","geometry":{"type":"MultiPolygon","coordinates":[[[[68.81,39.88],[69.03,39.9],[69.45,39.98],[71.41,41.03],[71.78,41.31],[73.02,40.87],[71.84,39.88],[70.94,39.83],[70.1,39.66],[68.92,39.51],[68.44,39.58],[68.41,39.72],[68.54,39.89],[68.81,39.88]]]]}}

Fossils

In the Zaaminskaya suite (зааминской свите), there are remains of upper Silurian and lower Devonian (Ludlow-Lochkovian stages) corals and brachiopods Favosites weberi Orlov, F. ferganensis (Orlov), F. cf. clarus Yanet, Squameofavosites zaaminicus Chekh., Sq. nikiforovae Chekh., Sq. thetidis Chekh., Cladopora rectilineata Simpson, Pachyfavosites markovskii Sow., Neomphyma originata Soshk., Pseudamplexus bohemicus (Pocta), Spirifer favositicus Nikif., Eoreticularia tschernyschewi Nal., Schellwienella ex gr. pecten L., Retziella weberi Nikif., Lissatrypa camelina (Buch.), Gypidula pelagica (Barr.), Stropheodonta costatula (Barr.), Protathyris didyma Dalm., Proreticularia cf. carens Barr. and others.

Age

It is noted from remains of upper Silurian and lower Devonian (Ludlow-Lochkovian stages)

Age Span:

Beginning stage:

Gorstian

Fraction up in beginning stage:

0.5

Beginning date (Ma):

425.87

Ending stage:

Lochkovian

Fraction up in the ending stage:

0.5

Ending date (Ma):

415.70

Depositional setting

Depositional pattern:

Additional Information

Compiler:

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