Uchbulak Fm

Along the spring Uchbulak, northern slope of the Karachatyr Range, Southern Fergana. A.D. Miklouho-Maclay, 1956 (293, p. 1153); F.R. Bensh, 1959 (382, p. 77). Stratotype - 3. Karachatyr, northwest wing of the Dzhilginsay anticline, east of the highway crossing the range between the villages of Pakhta (Khauz) and Karavan, northern wing of the Karachatyr syncline east of the spring Uchbulak, Kyrgyzstan.

Synonym: Uchbulakian, Uchbulak Suite, Учбулакская св.

The suite is considered in the volume of the foraminiferal zones Montiparus montiparus (lower) and Triticites quasiarcticus - T. (= Ferganites Miklukho-Maclay, 1959) ferganensis (upper), which divide the section into two sub-suites. Lower sub-suite (thickness of 425m) of coarse-rhythmic structure, where each rhythm begins with conglomerates, gravelites, or sandstones and ends with siltstone (aleurolites) and claystones with nodules and interbeds of limestones. Upper sub-suite lithologically divides into three parts. Lower part (thickness of 320m) - rhythmic interbedding of sandstones and siltstones, rare interbeds of gravelites and small-pebble conglomerates; at the base (thickness of 34m) - gravelites and conglomerates with interbeds of limestone. Middle part (thickness of 800-850m) coarse-clastic - sandstones, often poorly sorted, passing into gravelites and conglomerates, with subordinate interbeds of siltstone (aleurolites) and lenticular layers of limestones. The upper part (thickness of 230-340m) is predominantly flyschoid - thin alternation of fine-grained sandstones and siltstones, rare lenses and layers of conglomerates and massive sandstones. Thickness in subsurface is 1350-1500m. Total thickness is 1775-1925m.

The suite is considered in the volume of the foraminiferal zones Montiparus montiparus (lower) and Triticites quasiarcticus - T. (= Ferganites Miklukho-Maclay, 1959) ferganensis (upper), which divide the section into two sub-suites. Lower sub-suite – contains foraminifers - Protriticites subschwagerinoides inflatus Bensh, Obsoletes minutus asiaticus Bogush, Montiparus montiparus (Ehr. et Moel.), M umbonoplicatus (Raus. et Bel.), Triticites (= Schwageriniformis Bensh, 1996) expressus Anosova, Quasifusulina sp. Upper sub-suite, lower part contains foraminifers - Montiparus paramontiparus Ros., Ferganites ferganensis M.-Macl., at the top - a horizon with ammonoids - Agathiceras uralicum Karp., Aristoceras chkalovi Ruzh., Subkargalites ferganensis A.Popov, Emilites incertus (Bose) and others. Middle part contains foraminifers Schwageriniformis schwageriniformis (Raus.), S. fasiformis (Bensh), S. gissaricus (Bensh), Ferganites ferganensis (M.-Macl.), Rugosofusulina prisca ovoidea Bensh, etc.