干旱区生态环境知识资源中心(Arid): A 43-ka mineral magnetic record of environmental variations from lacustrine sediments of Schirmacher Oasis, East Antarctica

Arid

DOI	10.1016/j.catena.2021.105300
	A 43-ka mineral magnetic record of environmental variations from lacustrine sediments of Schirmacher Oasis, East Antarctica
	Warrier, Anish Kumar; Mahesh, Badanal Siddaiah; Mohan, Rahul; Shankar, Rajasekhariah
通讯作者	Warrier, AK (corresponding author), Manipal Acad Higher Educ, Ctr Climate Studies, Dept Civil Engn, Manipal Inst Technol, Manipal 576104, Karnataka, India.
来源期刊	CATENA
ISSN	0341-8162
EISSN	1872-6887
出版年	2021
卷号	202
英文摘要	Glacial-interglacial climatic and environmental variations recorded in lake-bed sediments of Schirmacher Oasis (SO), East Antarctica, are rare; limited data exist on the past behavior of the East Antarctic Ice Sheet (EAIS). In this work, we present the mineral magnetic properties of a radiocarbon-dated sediment core, spanning the past 43,000 years, from a land-locked lake L-49 in SO. We also performed Scanning Electron Microscopic-Energy Dispersive X-ray Spectroscopic (SEM-EDS) studies on magnetic extracts to confirm the magnetic mineralogy. The values of magnetic susceptibility (chi(lf)) and saturation isothermal remanent magnetization (SIRM) are relatively low during the Holocene but high during the last glacial period. Sediments of the last glacial period are composed mainly of coarse-grained (multi-domain - MD) magnetite/titanomagnetite (high values of S-20 - an MD proxy, low susceptibility of anhysteretic remanent magnetism (chi(ARM))/SIRM ratio values and high S-ratio values) indicating a stronger intensity of physical weathering in the Lake L-49 catchment. The mineralogy is confirmed by SEM-EDS data for magnetic extracts. Principal Component Analysis (PCA) of the data suggests three processes affecting magnetic properties of the lake sediments, i.e., ferrimagnetic input, biogenic processes and aeolian input. During deglaciation, a shift in the magnetic properties is documented: a decrease in chi(lf) values from 18.6 cal ka BP onwards suggests melting of the snow and ice in the catchment thus leading to a significant production of fine-grained iron oxide minerals. At similar to 12.77 cal ka BP, high values of chi(lf) and S-20 ratio indicates cooling which is related to the Antarctic Cold Reversal (ACR). The Early Holocene Climate Optimum is distinctly imprinted in our record as a sudden decrease in chi(lf) values and an increase in magnetic grain size ratio values (indicating finer iron oxide grains), suggesting a rapid thawing of the ice-sheet in response to a warm climate. The Mid-Holocene Hypsithermal (from 5.8 to 3.5 cal ka BP) and Neoglaciation (3.6 cal ka BP onwards) that are evident in this study correspond with reconstructions from lake and marine sediment, and ice-core records from Antarctica.
英文关键词	Magnetic susceptibility Magnetic grain size Weathering Aeolian Lake sediments East Antarctica
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000643594100058
WOS关键词	CLIMATE VARIABILITY ; LARSEMANN HILLS ; LAKE-SEDIMENTS ; GRAIN-SIZE ; ICE-CORE ; EVOLUTION ; HISTORY ; TEMPERATURE ; CALIBRATION ; DEPOSITION
WOS类目	Geosciences, Multidisciplinary ; Soil Science ; Water Resources
WOS研究方向	Geology ; Agriculture ; Water Resources
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/349803
作者单位	[Warrier, Anish Kumar] Manipal Acad Higher Educ, Ctr Climate Studies, Dept Civil Engn, Manipal Inst Technol, Manipal 576104, Karnataka, India; [Mahesh, Badanal Siddaiah; Mohan, Rahul] Minist Earth Sci, Natl Ctr Polar & Ocean Res NCPOR, Vasco Da Gama 403804, Goa, India; [Shankar, Rajasekhariah] Mangalore Univ, Dept Marine Geol, Mangalagangothri 574199, Karnataka, India; [Shankar, Rajasekhariah] Vishwa Prakrithi Apartments 29,4th Main, Bengaluru 560018, Karnataka, India
推荐引用方式 GB/T 7714	Warrier, Anish Kumar,Mahesh, Badanal Siddaiah,Mohan, Rahul,et al. A 43-ka mineral magnetic record of environmental variations from lacustrine sediments of Schirmacher Oasis, East Antarctica[J],2021,202.
APA	Warrier, Anish Kumar,Mahesh, Badanal Siddaiah,Mohan, Rahul,&Shankar, Rajasekhariah.(2021).A 43-ka mineral magnetic record of environmental variations from lacustrine sediments of Schirmacher Oasis, East Antarctica.CATENA,202.
MLA	Warrier, Anish Kumar,et al."A 43-ka mineral magnetic record of environmental variations from lacustrine sediments of Schirmacher Oasis, East Antarctica".CATENA 202(2021).