Shakhaman Fm

By the village of Shakhaman, South Pre-Aral. I.M. Abdazimov in 1996. Stratotype - section of well 24-G, 28km east-northeast of the village of Shakhaman.

Synonym: Shakhamanskaya Suite, Шахаманская св.

Coastal-marine gray-colored terrigenous formations with layers of red-colored. Divided into lower and upper sub-suites. Upper - sands, sandstones with layers of clays. Thickness 28-165m. Lower - clays, siltstone (aleurolites), sands, gray-colored sandstones. Thickness 50-260m.

In the stratotype, the section of the suite is represented: lower sub-suite (int.674-651m) - fine- and medium-grained sands, glauconite-quartz-feldspar, well-sorted, greenish-gray with carbonized plant detritus, clayey pebbles. Contains layers of greenish-gray and gray clays, siltstone (aleurolites), and quartz-glauconite sandstones. Int. 651-640m - alternation of fine- and medium-grained sands, sandstones, dense silty (aleuritic) clays, and sandy siltstone (aleurolites); color greenish-gray, gray. Int. 640-611m - fine- and medium-grained sands, quartz-feldspar, glauconitic, greenish-gray with layers of clays and sandstones. Int. 611-599m - sandstones, fine-grained sands, glauconitic, quartz-feldspar, greenish-gray with layers of clays and siltstone (aleurolites) Int. 599-579m - aleuritic clays, gray, greenish-gray, in places horizontally layered, with carbonized plant detritus, in places sandy, lumpy. Upper sub-suite (int. 579-550m) - fine- and medium-grained sands, quartz-glauconitic, greenish-gray with layers of gray and greenish-gray sandstones and clays. Int. 550-515m - sandstones, fine- and medium-grained sands, glauconitic, quartz-feldspar, greenish-gray, well-sorted with layers of greenish-gray and gray clays. Thickness of lower sub-suite 50-260 m, upper 28-165 m. For the suite, increased silt content (aleuriticity) is characteristic, in sands and sandstones, a large number of clay-siltstone interlayers often takes on the character of interbedding of sands, clays, and siltstones (Polyakov, 1963). In the upper part of the sub-suite, red-colored rocks are noted.

In the lower sub-suite, foraminifers - Reophax kysylcumensis Suleim., Haplophragmoides turonicus Zhuk., Spironatus gissarensis N. Byk., Gaudryinopsis akrabatensis (Zhuk.), G. asiaticus (N. Byk.), Paragaudryina inornata Suleim., Valvulineria lenticula Reuss, Arenobulimina minima Vass., Gavelinella vesca (N. Byk.), Hedbergella ex gr. cretacea (Orb.), Praebulimina reusii (Morr.); marine bivalve mollusks - Inoceramus labiatus (Shloth.), Corbula muschketovi (Böhm.); spores and pollen (%) - Selaginella ferganica Fok. (0-2), Foraminisporis wonthaggiensis (Cook. et Dett.) Dett. (1-1.4), Taurocusporites reduncus (Bolch.) Stov. (0.5-4.5), Stenozonotriletes radiatus Chl. (2-3), Regubivesiculites aralicus (Bolch.) Chl. (3.5-6), Classopolis classoides Pf. (3-12), Steevesipollenites turtcullensis Obon. (1-3.5), Tricolpites sp. (4-8)

In the upper sub-suite, foraminifers - Paragaudryina inornata media Suleim., Gaudryinella pseudoasiatica antiqua Suleim., Gavelinella vesca (N. Byk.), marine bivalve mollusks - Liostrea ljangarensis Vinok., L. jaxartensis Sim.; spores and pollen - Heliosporites kemensis (Chl.) Sriv. (0-1), Rauseisporites reticulatus Pocock. (7-44), Gnetaceaepollenites evidens (4-20), Tricolpites sp. (7-22), Tricolporites striatellus N. Mtsch. (1-5).