Chemical analysis from two sediment cores of lake Dauriat and lake Oksana from Schefferville, subarctic Québec ...

• Main Authors: Aebischer, Stéphane, Cloquet, Christophe, Carignan, Jean, Maurice, Pierre, Pienitz, Reinhard
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2017
• Subjects: Subarctic
• Online Access: https://dx.doi.org/10.1594/pangaea.874837; https://doi.pangaea.de/10.1594/PANGAEA.874837

Iron mining in Schefferville (1939-1977) in subarctic Quebec has left behind large numbers and quantities of tailing deposits. The impact of past mining activity on aquatic ecosystems in the Schefferville area has been studied using geochemical and isotopic (Pb, Zn and Fe) analyses of lake sediments, ore deposits, tailings and epiphytic lichens. Analysis of two sediment cores from Lakes Dauriat and Oksana reveals that the surface geochemical cycle of the Schefferville area has been profoundly disturbed by anthropogenic activity such as mining. Disturbances were particularly abrupt at the transitions from pre-mining to mining and mining to post-mining periods.Elemental and isotopic analyses of the lake sediments reveal four different end-member contributions to the lake sedimentation, with changes in terms of sources and source contribution observed throughout the sedimentation history. End-members were identified using Pb, Zn and Fe isotopes and are consistent for each element. Lead isotope ratios vary from ... : Supplement to: Aebischer, Stéphane; Cloquet, Christophe; Carignan, Jean; Maurice, Pierre; Pienitz, Reinhard (2015): Disruption of the geochemical metal cycle during mining: Multiple isotope studies of lake sediments from Schefferville, subarctic Québec. Chemical Geology, 412, 167-178 ...