气候变化领域集成服务门户(CCPortal): Relative paleointensity (RPI) and age control in Quaternary sediment drifts off the Antarctic Peninsula

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DOI	10.1016/j.quascirev.2019.03.006
	Relative paleointensity (RPI) and age control in Quaternary sediment drifts off the Antarctic Peninsula
	Channell J.E.T.; Xuan C.; Hodell D.A.; Crowhurst S.J.; Larter R.D.
发表日期	2019
ISSN	0277-3791
起始页码	17
结束页码	33
卷号	211
英文摘要	Lack of foraminiferal carbonate in marine sediments deposited at high latitudes results in traditional oxygen isotope stratigraphy not playing a central role in Quaternary age control for a large portion of the globe. This limitation has affected the interpretation of Quaternary sediment drifts off the Antarctic Peninsula in a region critical for documenting past instability of the West Antarctic Ice Sheet (WAIS) and Antarctic Peninsula Ice Sheet (APIS). Here we use piston cores recovered from these sediment drifts in 2015 during cruise JR298 of the RRS James Clark Ross to test the usefulness for age control of relative paleointensity (RPI) data augmented by scant δ 18 O data. Thermomagnetic and magnetic hysteresis data, as well as isothermal remanent magnetization (IRM) acquisition curves, indicate the presence of prevalent magnetite and subordinate oxidized magnetite (“maghemite”) in the cored sediments. The magnetite is likely detrital. Maghemite is an authigenic mineral, associated with surface oxidation of magnetite grains, which occurs preferentially in the oxic zone of the uppermost sediments, and buried oxic zones deposited during prior interglacial climate stages. Low concentrations of labile organic matter apparently led to arrested pore-water sulfate reduction explaining oxic zone burial and downcore survival of the reactive maghemite coatings. At some sites, maghemitization has a debilitating effect on RPI proxies whereas at other sites maghemite is less evident and RPI proxies can be adequately matched to the RPI reference template. Published RPI data at ODP Site 1101, located on Drift 4, can be adequately correlated to contemporary RPI templates, probably as a result of disappearance (dissolution) of maghemite at sediment depths >∼10 m. © 2019 Elsevier Ltd
英文关键词	Late Quaternary; Magnetic properties; Oxygen isotopes; Relative paleointensity; Sediments; West Antarctica
语种	英语
scopus关键词	Glacial geology; Glaciers; Isotopes; Magnetic properties; Magnetite; Sediments; Stratigraphy; Submarine geology; Sulfur compounds; Antarctic Peninsula Ice Sheet; Isothermal remanent magnetization; Late quaternary; Oxygen isotope stratigraphy; Oxygen isotopes; Relative paleointensity; West antarctic ice sheets; West antarctica; Oxic sediments; carbonate sediment; core analysis; hysteresis; interglacial; maghemite; magnetite; marine sediment; oxygen isotope; paleointensity; Quaternary; remanent magnetization; sediment analysis; sequence stratigraphy; Antarctic Ice Sheet; Antarctic Peninsula; Antarctica; West Antarctic Ice Sheet; West Antarctica
来源期刊	Quaternary Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151969
作者单位	Department of Geological Sciences, University of Florida, 241 Williamson Hall, POB 112120, Gainesville, FL 32611, United States; School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, United Kingdom; Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ, United Kingdom; British Antarctic Survey, Madingley Road, Cambridge, CB3 0ET, United Kingdom
推荐引用方式 GB/T 7714	Channell J.E.T.,Xuan C.,Hodell D.A.,et al. Relative paleointensity (RPI) and age control in Quaternary sediment drifts off the Antarctic Peninsula[J],2019,211.
APA	Channell J.E.T.,Xuan C.,Hodell D.A.,Crowhurst S.J.,&Larter R.D..(2019).Relative paleointensity (RPI) and age control in Quaternary sediment drifts off the Antarctic Peninsula.Quaternary Science Reviews,211.
MLA	Channell J.E.T.,et al."Relative paleointensity (RPI) and age control in Quaternary sediment drifts off the Antarctic Peninsula".Quaternary Science Reviews 211(2019).