Consistent grain size distribution of pedogenic maghemite of surface soils and Miocene loessic soils on the Chinese Loess Plateau

2009 ◽  
Vol 25 (3) ◽  
pp. 261-266 ◽  
Author(s):  
Junsheng Nie ◽  
Yougui Song ◽  
John W. King ◽  
Ramon Egli
2013 ◽  
Vol 79 (3) ◽  
pp. 465-470 ◽  
Author(s):  
Junsheng Nie ◽  
Yougui Song ◽  
John W. King ◽  
Rui Zhang ◽  
Xiaomin Fang

AbstractMagnetic grain-size variations have been used as sensitive paleoclimate proxies to investigate the evolution of the East Asian summer monsoon, but their relationship with temperature and precipitation is not entirely clear. Here we find that two magnetic grain-size proxy records (χARM/χLF and χARM/SIRM, where χARM, χLF and SIRM are anhysteretic remanent magnetization susceptibility, magnetic susceptibility measured at 470 Hz and saturation isothermal remanent magnetization, respectively) of Chinese loess and red-clay sediments co-vary during the last 6 Ma, except between ~ 4.5 and 2.6 Ma, when these two records had opposite trends. We attribute this disparate behavior to the different responses of χARM/χLF and χARM/SIRM to temperature and precipitation during ~ 4.5–2.6 Ma, when temperature and precipitation on the Chinese Loess Plateau were decoupled. A comparison of the loess and red-clay χARM/χLF and χARM/SIRM records with the global ice-volume proxy records reveals that χARM/χLF is more sensitive to temperature variations than χARM/SIRM. The results suggest that temperature on the Chinese Loess Plateau had a cooling trend from ~ 4.5 to ~ 2.6 Ma, whereas rainfall tended to increase. Our studies demonstrate that joint analysis of loess χARM/χLF and χARM/SIRM records can reveal paleoclimatic information that cannot be revealed by a single parameter.


2007 ◽  
Vol 26 (1-2) ◽  
pp. 230-242 ◽  
Author(s):  
Maarten A. Prins ◽  
Mirjam Vriend ◽  
Govert Nugteren ◽  
Jef Vandenberghe ◽  
Huayu Lu ◽  
...  

2016 ◽  
Vol 85 (2) ◽  
pp. 290-298 ◽  
Author(s):  
Shuzhen Peng ◽  
Qingzhen Hao ◽  
Luo Wang ◽  
Min Ding ◽  
Wei Zhang ◽  
...  

Widespread loess deposits in the Central Shandong Mountains yield valuable paleoclimatic records for this currently semi-humid monsoonal region of northern China. The grain-size distribution and major element composition for bulk samples and two grain-size fractions (< 20 and 20–63 μm) for the loess in the Central Shandong Mountains were compared with loess from the Chinese Loess Plateau and sediment from the Yellow River to help determine its provenance. The presence of a significant percentage of medium- and coarse-silt, and the difference in relatively immobile major element ratios of TiO2/Al2O3 and K2O/Al2O3 for the < 20 and 20–63 μm fractions, suggests that sediment that forms the loess deposits in the Central Shandong Mountains was not blown directly from the northern deserts of China as is the case for the loess deposits of the Chinese Loess Plateau. Rather, this suggests that sediments exposed during glacial times on the North China fluvial plain, including the floodplain of the Yellow River, were the major dust source for the loess in the Central Shangong Mountains. In addition, the wide distribution of perimontane loess in the Central Shandong Mountains region indicates the occurrence of strengthened local aridification during glacial times since the middle Pleistocene.


2001 ◽  
Vol 28 (10) ◽  
pp. 2097-2100 ◽  
Author(s):  
Z. L. Ding ◽  
Z. W. Yu ◽  
S. L. Yang ◽  
J. M. Sun ◽  
S. F. Xiong ◽  
...  

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