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The world’s largest bauxite-bearing province, Fouta Djallon–Mandingo (West Africa). Part IV: a zoning mechanism in laterite bauxite-bearing weathering crustстатья
Информация о цитировании статьи получена из
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 15 февраля 2024 г.
- Авторы: Makarova M.A., Mamedov V.I., Boeva N.M., Shipilova E.S., Vnuchkov D.A., Bortnikov N.S.
- Журнал: Geology of Ore Deposits
- Том: 65
- Номер: 3
- Год издания: 2023
- Издательство: Maik Nauka/Interperiodica Publishing
- Местоположение издательства: Russian Federation
- Первая страница: 224
- Последняя страница: 239
- DOI: 10.1134/S1075701523030030
- Аннотация: The results of detailed exploration and year-round observations of the hydrogeological regime at large deposits, as well as special hydrochemical studies of various types of water and changes in the gas com- position of the underground atmosphere in the lateritic weathering crust, of the very large bauxite-bearing province, Fouta Djallon–Mandingo, thanks to a reliable factual base, made it possible for the first time to draw a number of important conclusions about the conditions and features of zoning formation in the lateritic weathering profile. The weathering profile consists of two metasomatic columns spatially combined in plan, but vertically separated: an upper one, consisting of hydroxides and oxides of iron and aluminum, and a lower one, composed of clayey eluvium and products of hydration and decomposition of aluminosilicates—poly- mineral clays and kaolinite. In both columns, the processes of change begin with the same rainwater, but dif- fer in the hydrodynamic parameters in each of the columns. Changes in the weathering profile occur in accor- dance with the main patterns of low-temperature infiltration metasomatism. The modern hydrogeological and gas regime in bauxite-bearing lateritic covers controls the mineralogical and geochemical zoning. Fea- tures of biological and soil processes and hydrodynamics and hydrochemistry in the weathering profile lead to a threshold nature of the change in physicochemical and biochemical conditions, providing the action of geochemical (oxidation, reduction, gley, adsorption) barriers, which is the main mechanism of zonal distri- bution of matter in lateritic weathering crusts.
- Добавил в систему: Макарова Марина Александровна