Survey of a limestone lens in the middle course of the Skalny Stream in the eastern Sakhalin Mountains in 2019
Karst manifestations in the form of sinkholes and several cavities were found during a survey of a heavy limestone lens along the Skalny Stream of the upper Pilenga River (eastern Sakhalin Mountains) in 2019. The most significant of these is Snezhnaya Zebra Cave, which has an amplitude of 21 m, with a traced length of passages of 44 m, several entrances, and a small hall with ice cascades. A further survey is called for following excavation of snow and ice plugs from the cavities. Detection of other vertical cavities is possible in the body of the limestone lens. Thin layers of ancient volcanic ash are described from within the limestone.