Geochemical and isotopic characteristics of paleocavities mineral filling in the Upper Devonian-Lower Carboniferous limestones on the eastern slope of the Middle Urals (vicinity of Pershino village)
Автор: Dub S., Mizens G., Kuleshov V., Petrov O.
Журнал: Вестник геонаук @vestnik-geo
Рубрика: Научные статьи
Статья в выпуске: 7 (331), 2022 года.
Бесплатный доступ
Lithology and geochemistry of carbonate filling in ancient karst cavities in the Famennian-Tournaisian limestone sequence of the Rezh subzone at the eastern slope of the Middle Urals are considered. Mineral filling of paleocavities differs from typical modern subaerial speleothems. Caves are mainly filled with white massive coarse-grained calcite (cave spar), red-colored argillaceous-carbonate microgranular deposits (carbonates with an admixture of terra rossa, cave laminites) and collapse breccias, composed of host limestones fragments. The rare earth elements (REE) patterns and the isotopic composition of carbon indicate a very weak effect (or its absence) of soil or meteoric waters on the carbonate system: the speleothem calcite inherited these characteristics from the host limestones. At the same time, the isotopic composition of oxygen indicates the primary meteoric genesis of solutions and/or relatively high temperatures of calcite crystallization. Most likely, the studied speleothems were formed from solutions of surface origin circulating in the sedimentary strata for a long time (hypogene sediments).
Paleokarst, phreatic speleothems, terra rossa, collapse breccias, groundwater, ree, carbon and oxygen isotopes
Короткий адрес: https://sciup.org/149141023
IDR: 149141023 | DOI: 10.19110/geov.2022.7.4