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Correction of interstitial water changes in calibration methods applied to XRF core-scanning major elements in long sediment cores: Case study from the South China Sea ArchiMer
Chen, Quan; Kissel, Catherine; Govin, Aline; Liu, Zhifei; Xie, Xin.
Fast and non-destructive X-ray fluorescence (XRF) core scanning provides high-resolution element data that are widely used in paleoclimate studies. However, various matrix and specimen effects prevent the use of semi-quantitative raw XRF core-scanning intensities for robust paleoenvironmental interpretations. We present here a case study of a 50.8-m-long piston Core MD12-3432 retrieved from the northern South China Sea. The absorption effect of interstitial water is identified as the major source of deviations between XRF core-scanning intensities and measured element concentrations. The existing two calibration methods, i.e. normalized median-scaled calibration (NMS) and multivariate log-ratio calibration (MLC), are tested with this sequence after the...
Tipo: Text Palavras-chave: XRF core-scanning geochemistry; Major element calibration; Long sediment cores; Downcore water content; South China Sea.
Ano: 2016 URL: https://archimer.ifremer.fr/doc/00333/44457/44130.pdf
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Dynamic control on grain-size distribution of terrigenous sediments in the western South China Sea: Implication for East Asian monsoon evolution ArchiMer
Chen, Guocheng; Zheng, Hongbo; Li, Jianru; Xie, Xin; Me, Xi.
High-resolution oxygen isotope stratigraphy of Core MD05-2901, which is located off eastern Vietnam in the western South China Sea (SCS), was established and indicated that the core spans a time period of the past 450 ka. Based on the bulk density, fractional porosity and lithogenic content of the sediments, terrigenous mass accumulation rate (TMAR) was obtained, which is 4.9-6.0 g cm(-2) ka(-1) on average during interglacial stages, higher than that during glacial stages, i.e. 1.9-5.0 g cm(-2) ka(-1), which is different from northern and southern SCS which show higher TMAR in glacial stages. By principle component analysis of grain size distribution of all the samples, two main control factors (F1 and F2) were obtained, which are responsible for about 80%...
Tipo: Text Palavras-chave: South China Sea; Late Quaternary; Terrigenous sediments; Grain size; East Asian monsoon.
Ano: 2008 URL: https://archimer.ifremer.fr/doc/00207/31846/30290.pdf
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Turbidite deposition in the southern South China Sea during the last glacial: Evidence from grain-size and major elements records ArchiMer
Zhao, Yulong; Liu, Zhifei; Colin, Christophe; Xie, Xin; Wu, Qiong.
High-resolution grain size and major element geochemical measurements were performed on the marine sediments of Core MD05-2895 to help understand the formation of turbidite sequences. Grain-size results show that these turbidite sediments contain more coarse sediment grains than normal marls. The coarse sediment grains are mostly derived from relict sediments on the Sunda Shelf. Relict sediments are composed mainly of quartz, feldspar, tephra and a few titaniferous or ferruginous heavy minerals. Corresponding to the concentration of these minerals, increases in Si/Al, K/Al, Ti/Al and Fe/Al ratios are observed in the turbidite layers. As all the observed turbidite sequences were deposited during the last glacial, the occurrence of these turbidity events is...
Tipo: Text Palavras-chave: Southern South China Sea; Last glacial; Turbidite; Grain-size analyses; XRF Core Scanner.
Ano: 2011 URL: https://archimer.ifremer.fr/doc/00213/32464/30929.pdf
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