Browse by author
Lookup NU author(s): Dr Tatiana Goldberg
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
Pyrite bearing barite concretions are abundant in black shales of the Early Cambrian Niutitang Formation in China. Barite in these concretions exhibits greatly elevated d34S and d18O values, averaging 685‰ and 201‰, respectively. Such high values indicate precipitation of barite during diagenesis at an advanced stage of bacterial sulphate reduction forming at the “barite front”. Pyrite sulphur has a relatively constant isotopic composition of ~10‰ in both concretions and host rock and likely formed prior to barite. Fluctuating methane flux into the zone of anaerobic methane oxidation led to the consumption of sulphate and release of barium into higher sediment layers. During radial concretion growth Ba2+ interacted with SO42- bearing fluids of various concentrations and isotopic compositions over a prolonged period, resulting in a lack of any systematic correlation between sulphate d34S and d18O values throughout the concretion.
Author(s): Goldberg T, Mazumdar A, Strauss H, Shields GA
Publication type: Article
Publication status: Published
Journal: Organic Geochemistry
ISSN (print): 0146-6380
ISSN (electronic): 1873-5290
Altmetrics provided by Altmetric