Karst and Caves in Carbonate Rocks, Salt and Gypsum – poster 2013 ICS Proceedings FIELD MEASUREMENTS OF GYPSUM DENUDATION RATE IN KULOGORSKAYA CAVE SYSTEM Nikolay Franz1, Sergey Sorokin2,3, Alexandra Alexeeva4, Irina Inshina4, Olga Novysh3, Anton Kazak3 1Arkhangels Speleological Association “Labirinth”, Arkhangels, Russia,
[email protected] 2Tver State University, Zhelyabova 33, Tver, Russia,
[email protected] 3Arkhangels Speleological Association “Labirinth”, Arkhangels, Russia 4Tver State University, Tver, Russia Results of measurements of karst denudation rate in natural conditions in Kulogorskaya cave system are reported. Taking into consideration relatively high rate of denudation in gypsum caves we have used simplified MEM measurement method. Observation of hydrological situation suggests that most of the dissolution in caves of the area occurs during a few days of spring flood. Here we report results of measurement at 62 points located at 6 sites for the period from 2003 to 2012. Data analysis gives us average retreat rate of 0.0448 mm/day, while point is underwater. Confidence interval for this value is 0.0379 to 0.0516 mm/day. 1. Introduction annual rainfall 560 mm. The coldest month – January (average long-term temperature -13.0 °C). The warmest Kulogorskaya cave system includes 7 caves, three of which month – July (average long-term temperature +15.4 °C). constitute the largest cave system in Russia in a gypsum, with a total length of surveyed passages more than 17.5 km. Karstifiable rocks of massif are represented by gypsum and dolomite of Permian age. Primary karst rock is gypsum, Cave system is studied by speleologists from Arkhangels, St. forming homogeneous strata ranging from 0.2 to 7 m, Petersburg, Moscow, Tver and other cities under the guidance interleaved with dolomites.