Carbon isotopic composition of whewellite (CaC2O4·H2O) from different geological environments and its significance
1993; Elsevier BV; Volume: 106; Issue: 1-2 Linguagem: Inglês
10.1016/0009-2541(93)90169-j
ISSN1872-6836
Autores Tópico(s)Geological and Geochemical Analysis
ResumoCarbon isotopic composition of whewellite (CaC2O4·H2O) varies significantly among individual types of occurrences from the Bohemian Massif, Czech Republic. The δ13C-values of whewellite found inside pelosiderite concretions in the coal-bearing Carboniferous Kladno Basin are unusually high from + 3.2 to + 14.7‰, indicating influence of bacterial activity on the oxalate carbon isotopic composition. In the Tertiary Northern Bohemian Basin, where the depth of burial and coalification grades are much lower, the δ13C-values of two whewellite samples are − 6.9 and − 14.2‰. Whewellites from low-temperature hydrothermal veins of the Příbram uranium deposits, where bacterial processes are highly unlikely, have δ13C-values of − 31.7 to − 28.4‰, identical to carbon isotopic composition of underlying black shales.
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