FOSSILIZED BIOMATS AS THE POSSIBLE SOURCE OF HIGH NATURAL RADIONUCLIDE CONTENT AT THE JURASSIC ÚRKÚT MANGANESE ORE DEPOSIT, HUNGARY
Abstract
DOI: 10.26471/cjees/2018/013/041
The 220Rn and 222Rn concentration in the Úrkút Manganese Formation is anomalously high, and it causes health risk for the attendants of the Úrkút Manganese Mine. In this study we suggest a new model for the high ratio of different natural radionuclides by the new genetic model of the Úrkút Manganese Formation. Fossilized Fe-rich biomats were found in the whole section of the deposit. Based on these, the formation of different types of Mn-ores by one or two step microbial mediation can be assumed. The biomats represent large amounts of organic matter offering large surfaces with negative ligands, as well as poorly ordered mineral phases like ferrihydrite and clay minerals with large and reactive surfaces. These features offer high capability of cation binding, among them ions of radioactive elements, which could be fixed on the active or inactive organic matter, as well as on mineral surfaces. The decay of fixed nuclides could result high 220Rn and 222Rn concentration in the Úrkút Mine.
- biomats
- black
- shale
- geomicrobiology
- radon
- natural
- radionuclide