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 (<0.1 μm). Magnetic parameters and non-magnetic variables analysed by multivariate statistics reveal significant differences between silt facies (e.g. mass-specific susceptibility χ=109.6×10-8 m3 kg-1, remanent coercivity Hcr=49.2 mT and total organic carbon (TOC)=1.11%) and sand facies (e.g. χ=82.1×10-8 m3 kg-1, Hcr=44.7 mT and TOC=0.70%), and four recent depositional sub-environments were identified and characterized in Lake Anónima. This multiparameter analysis contributes to the understanding of present-day lacustrine dynamic and sedimentary processes. Lake Anónima may provide a useful analogue for the interpretation of other lacustrine basins in the Antarctic region. © Antarctic Science Ltd 2017
Documento: | Artículo |
Título: | Sedimentary analysis and magnetic properties of Lake Anónima, Vega Island |
Autor: | Chaparro, M.A.E.; Chaparro, M.A.E.; Córdoba, F.E.; Lecomte, K.L.; Gargiulo, J.D.; Barrios, A.M.; Urán, G.M.; Manograsso Czalbowski, N.T.; Lavat, A.; Böhnel, H.N. |
Filiación: | Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires (CIFICEN, CONICET-UNCPBA), Pinto 399, 7000 Tandil, Argentina Centro Marplatense de Investigaciones Matemáticas (CEMIM), Facultad de Ciencias Exactas y Naturales UNMDP, CONICET, Mar del Plata, Argentina Instituto de Ecorregiones Andinas (INECOA), Universidad Nacional de Jujuy-CONICET. Instituto de Geología y Minería, Av. Bolivia 1661 (4600), San Salvador de Jujuy, Argentina Centro de Investigaciones en Ciencias de la Tierra (CICTERRA), CONICET Av. Vélez Sarsfield 1611, X5016GCA Córdoba, Argentina Universidad Nacional de Córdoba, Facultad de Ciencias Exactas Físicas y Naturales, Av. Vélez Sarsfield 1611, X5016CGA Córdoba, Argentina Universidad de Granada, Av. del Hospicio, s/n, 18010 Granada, Spain Instituto Antártico Argentino (IAA), 25 De Mayo 1143, San Martín, Provincia de Buenos Aires, Argentina Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires (CIFICEN, CONICET-UNCPBA), Olavarría, Argentina Centro de Geociencias (UNAM), Blvd. Juriquilla 3001, 76230 Querétaro, México |
Palabras clave: | Antarctica; environmental magnetism; grain size analysis; hydrochemical studies; lake sediments; multivariate statistics |
Año: | 2017 |
Página de inicio: | 1 |
Página de fin: | 16 |
DOI: | http://dx.doi.org/10.1017/S0954102017000116 |
Título revista: | Antarctic Science |
Título revista abreviado: | Antarct. Sci. |
ISSN: | 09541020 |
CODEN: | ANTSE |
Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_09541020_v_n_p1_Chaparro |