Sedimentary analysis and magnetic properties of Lake AnoÌnima, Vega Island

• Published in: Antarctic science 2017-10, Vol.29 (5), p.429
• Main Authors: Chaparro, Marcos A E, Chaparro, Mauro A E, Córdoba, Francisco E, Lecomte, Karina L, Gargiulo, José D, Barrios, Ana M, Urán, Gimena M, Manograsso Czalbowski, Nadia T, Lavat, Araceli, Böhnel, Harald N
• Format: Article
• Language: English
• Subjects: Analytical methods; Antarctic zone; Basins; Bottom sediments; Climate change; Coercivity; Creeks & streams; Data processing; Evaporation; Ferrimagnetism; Fourier transforms; Grain size; Greigite; Hydrology; Identification; Inflow; Infrared analysis; Infrared spectroscopy; Lake bottom; Lake deposits; Lake sediments; Lakes; Magnetic permeability; Magnetic properties; Magnetism; Magnetite; Meltwater; Minerals; Multivariate analysis; Organic carbon; Permafrost; Sediment; Sediment composition; Sedimentary facies; Sediments; Snowmelt; Spatial variations; Statistical analysis; Statistical methods; Streams; Studies; Summer; Total organic carbon; Water inflow; Water levels; X-ray diffraction
• ISSN: 0954-1020; 1365-2079
• DOI: 10.1017/S0954102017000116

During the summer Lake Anónima experiences important changes in salinity and lake level fluctuations. Physicochemical data and field observations indicate that evaporative processes are dominant and that the water inflow is mainly provided by snow meltwater and streams. A multiproxy analysis of data from lake bottom sediments suggests that the main surface stream located south-west of the lake controls the clastic input and the spatial variation of sediment composition. Through an integrated analysis (magnetic, X-ray diffraction and Fourier transform infrared spectroscopy studies) magnetite and greigite minerals were identified in these lake sediments. Such ferrimagnetic minerals have ultra-fine grain sizes (