Paleoenvironments of a proglacial lake in Schirmacher Oasis, East Antarctica: Insights from quartz grain microtextures

• Published in: Polish Polar Research
• Main Authors: Mazumder, Abhijit, Govil, Pawan, Kar, Ratan, Gayathri, Narath Meethal
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Walter de Gruyter GmbH 2017
• Subjects: Antarc*; Antarctica; East Antarctica; Polar Research
• Online Access: http://dx.doi.org/10.1515/popore-2017-0002; http://content.sciendo.com/view/journals/popore/38/1/article-p1.xml; http://www.degruyter.com/view/j/popore.2017.38.issue-1/popore-2017-0002/popore-2017-0002.pdf

Abstract Eighteen sediment samples from a 36 cm long sediment core retrieved from a proglacial lake (namely P 11) situated in the Schirmacher Oasis, East Antarctica, were analysed for the study of quartz grain morphology and microtexture, along with sand percentage, to reconstruct the paleoenvironmental changes in the lake during the Holocene. The age of the core ranges from 3.3 ka BP to 13.9 ka BP. The quartz grain morphology and microtexture reveal significant evidences of glacial transport along with some eolian and aqueous activities. On the basis of predominance of these signatures and the zonation from CONISS Cluster Analysis on the percentages of characteristic grain morphology and microtextures, the entire core has been subdivided into three major zones. From the paleoenvironmental perspective, it can be concluded that there is an onset of interglacial period at the advent of Holocene (12.3 ka BP), which reigned until 5.3 ka BP and thereafter, again a glacial environment prevailed until 3.3 ka BP with some variations in-between. The results indicate probable alternative colder and less colder phases in the study area, which are also well supported by the respective sand percentages in the sediments.