Age and sedimentary environments of the Paleocene deposits in the Carpathian Skyba Nappe based on micropaleontological and sedimentological data

The results of micropaleontological and sedimentological studies of the Paleocene sediments such as the Upper Member of the Stryi Formation and the Yamna Formation located in the Skyba Nappe in the Ukrainian Outer (Flysh) Carpathians are represented. Sedimentological features of the flysch successions (including the sedimentary succession along the Prut River in the city of Yaremche) proved that the Upper Member of the Stryi Formation is represented mainly by turbidites; the lower part of the Yamna Formation (variegated Yaremcha Horizon) is composed of red and green clay hemipelagites and turbidites, and the upper part of the Yamna Formation (Yamna sandstone) consists of deposits of high-density turbidite currents and grain flows. The calcareous nannoplankton: NP1, NP2, NP3 and NP4 zones as well as the foraminifera: planktonic Globoconusa daubjergensis Zone (Danian Stage) and benthic Rzehakina epigona Subzone of Rzehakina fissistomata Zone, s. l. (the early Paleocene) are identified in the Upper Member of the Stryi Formation. The calcareous nannoplanktonic NP4, NP5, NP6 zones are distinguished in the Yaremcha Horizon and NP6, NP8, NP9 zones are identified in the Yamna sandstone. The agglutinated foraminifera including Rzehakina fissistomatа, Rz. epigona, Caudammina ovula, Hormosina velascoense, Glomospirella grzybowskii, Saccammina placenta, Paratrochamminoides irregularis are dominated in the Yamna Formation. The age of the Stryi Formation (Upper Member) is established as Danian–partly Zealandian, and the age of the Yamna Formation is Zealandian–Thanetian based on nannoplankton and foraminifera data. Deep-water agglutinated foraminifera (DWAF) belonging to the genera Rhabdammina, Hyperammina, Dendrophrya, Ammodiscus, Glomospira, Hormosina, Reophax, Haplophragmoides, Recurvoides, Trochamminoides, Paratrochamminoides, Spiroplectammina, Karreriella are dominated in the background hemipelagic clay deposits and make up to 100% of the tests in the microfaunal associations, that suggests the lower bathyal-abyssal depths of the sedimentary paleobasin The channel deposits (Yamna sandstone) and interchannel sediments (Upper Member of the Stryi Formation) of the ancient deep-sea fan are identified in the Paleogene flysch.