Chronostratigraphy of the sedimentary record of Limnopolar Lake, Byers Peninsula, Livingston Island, Antarctica

• Published in: Antarctic Science
• Main Authors: Toro, M., Granados, I., Pla-Rabes, S., Giralt, Santiago, Antoniades, Dermot, Galán, Luis, Martínez Cortizas, Antonio, Soo Lim, Hyoun, Appleby, P. G.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press 2013
• Subjects: Radiocarbon dating; Tephrachronology; 137Cs; Deglaciation; Drepanocladus longifolius; 210Pb; Antarctic; Antarctic Peninsula; Byers; Byers peninsula; Limnopolar Lake; Livingston Island; South Shetland Islands; Antarc*; Antarctic Science; Antarctica; International Polar Year; Korea Polar Research Institute
• Online Access: http://hdl.handle.net/10261/74339; https://doi.org/10.1017/S0954102012000788

15 páginas, 7 figuras, 2 tablas. The chronostratigraphy of the sedimentary record of Limnopolar Lake, located on Byers Peninsula (Livingston Island, South Shetland Islands, Maritime Antarctica), is described based on radionuclides and radiocarbon age dating. The oldest moss macrofossil age was 6700 ± 50 yr BP (7510 ± 80 cal yr BP) from which the age/depth model estimates a basal age for the sedimentary record of c. 8300 cal yr BP, suggesting an earlier deglaciation of Byers Peninsula than reported in previous studies. Lithological units and other stratigraphic zones are described throughout the sediment core, showing different mineralogical composition and a fine alternation of clays and silty clays and moss layers of Drepanocladus longifolius. Based on magnetic susceptibility analyses, a number of probable primary and reworked tephra layers were identified, seven of them confirmed by SEM observations, and most of them in agreement with the regional tephrachronology stratigraphy for the north-west Antarctic Peninsula. Sedimentation rates showed no significant changes during the last 5000 years with the exception of an abrupt event that took place around 5400 cal yr BP, which implied the sedimentation of c. 30 cm of clays in a very short time, probably related to a period of glacial re-advance that caused abrupt changes in geomorphological processes in the catchment. Field work was supported by grants REN2000-0435-ANT from the Science and Technology Ministry (Spain) and POL2006-06635/CGL from the Education and Culture Ministry (Spain) in the framework of the International Polar Year 2007–09 activities. Laboratory analyses were supported by grants CTM2009-07869-E/ANT and CSD2007-00067 from the Science and Innovation Ministry (Spain) and grant PP12020 from KOPRI (Korea Polar Research Institute). Publication expenses have been covered by grant CTM2011-12973-E from the Science and Innovation Ministry (Spain). A. Quesada, A. Justel and C. Rochera, from the Limnopolar Project team, helped with coring in 2003 and S. ...