Color characteristics of Chinese loess and its paleoclimatic significance during the last glacial-interglacial cycle
The soil color is widely used in paleoclimate and paleoenvironment reconstructions in the Chinese Loess Plateau. To better understand the color spatial changes during the glacial -interglacial cycle, the soil color lightness (L-*), characteristic spectra, magnetic susceptibilities and mean grain siz...
Published in: | Journal of Asian Earth Sciences |
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Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2016
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Subjects: | |
Online Access: | http://ir.ieecas.cn/handle/361006/5846 https://doi.org/10.1016/j.jseaes.2015.11.013 |
Summary: | The soil color is widely used in paleoclimate and paleoenvironment reconstructions in the Chinese Loess Plateau. To better understand the color spatial changes during the glacial -interglacial cycle, the soil color lightness (L-*), characteristic spectra, magnetic susceptibilities and mean grain sizes of three loess-paleosol sequences were compared. Results showed that high L-* and low hematite to goethite ratios (Hm/Gt) appeared in loess units, and low e and high Hm/Gt ratios accompanied paleosol layers, indicating glacial -interglacial hydrothermal oscillation. L-* in the Yulin section was higher than in the Chaona and Lihuacun sections, indicating that different precipitations have great effect on L-*. Furthermore, Hm/Gt, magnetic susceptibility (chi(lf)), and mean grain size are correlated closely with L-*. L-* and Hm/Gt not only document climatic variations in the glacial -interglacial cycle vis-a-vis loess-paleosol sequences, but also can identify Heinrich cold events and millennial scale Dansgaard-Oeschger (D-O) warm events. It suggests that soil color responds sensitively to global climate change driven by ice volumes. L-* and Hm/Gt curves exhibit higher frequencies and larger amplitudes than magnetic susceptibility (chi(lf)) curves, indicating that L-* and Hm/Gt can be regarded as sensitive and reliable proxies for characterizing high-resolution climate change during the last glacial -interglacial cycle. (C) 2015 Elsevier Ltd. All rights reserved. |
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