Spatial variations in paleowind direction during the last glacial period in north China reconstructed from variations in the anisotropy of magnetic susceptibility of loess deposits
Spatial variations in paleowind direction during the last glacial period in north China reconstructed from variations in the anisotropy of magnetic susceptibility of loess deposits
复制标题
从黄土沉积物磁化率各向异性变化重建华北末次冰期古风向空间变化
DOI：
10.1016/j.tecto.2014.07.002
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发表时间：
2014-08
期刊：
影响因子：
2.9
通讯作者：
Chenglong Deng
中科院分区：
文献类型：
--
作者：
Junyi Ge;Zhengtang Guo;Deai Zhao;Ying Zhang;Tao Wang;Liang Yi;Chenglong Deng
中国黄土磁化率各向异性（AMS）被认为是确定古风向的有效工具。然而，AMS与古风向的关系仍是一个有争议的问题。本文报道了末次冰期中国黄土在不同坡角和坡向斜坡上的AMS测量结果。这些遗址位于中国黄土高原、西秦岭和祁连山东部边缘。结果表明：在同一区域内，尽管坡面暴露程度和坡角不同，磁线排列方向相似，但不同区域磁线排列方向不同；这些结果表明，风成沉积过程中磁性颗粒的排列是由空气环流决定的，而不是由斜坡表面的水流决定的，因此中国黄土的AMS可以用来确定古风向。此外，我们的研究结果表明，中国黄土的AMS主要由沙尘积累过程中发生的区域地面风流模式决定，而不是由大尺度大气环流的均匀模式决定。此外，由于风向受区域地形的显著影响，中国黄土的AMS可能具有探测过去区域地形显著变化的潜力。
Anisotropy of magnetic susceptibility (AMS) of Chinese loess is considered to be an effective tool for determining paleowind direction. However, the relationship between AMS and the paleowind direction is still a matter of debate. This study reports the results of AMS measurements of Chinese loess deposited during the last glacial period on slopes of varying slope angles and orientations. The sites are located on the Chinese Loess Plateau, in West Qinling, and on the eastern margin of Qilian Mountain. The results show that within the same region, magnetic lineations are clustered along similar orientations despite differences in slope exposure and slope angle, but that different regions exhibit different directions of magnetic lineation. These results suggest that the alignment of the magnetic grains during deposition of the eolian deposits was determined by air circulation rather than by water flow on the surface of the slopes, and therefore that the AMS of Chinese loess can be used to determine paleowind directions. In addition, our results indicate that the AMS of Chinese loess is determined mainly by the patterns of regional surface wind flow that occurred during dust accumulation rather than by the uniform pattern of large-scale atmospheric circulation. In addition, since wind direction is influenced significantly by regional topography, the AMS of Chinese loess may have the potential to detect significant changes in past regional topography.
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影响因子：
2
作者：
M. Colbert
通讯作者：
M. Colbert
上新世中期东亚气候重大变化：是青藏高原隆升引发还是全球变冷引发？
影响因子：
3
作者：
Ge, Junyi;Dai, Ying;Guo, Zhengtang
通讯作者：
Guo, Zhengtang
影响因子：
2.3
作者：
L. Thistlewood;Sun Jianzhong
通讯作者：
L. Thistlewood;Sun Jianzhong
DOI：
10.1130/2008.2444(05
发表时间：
2008-10
期刊：
Geological Society of America
影响因子：
--
作者：
Fang, X.;Langereis, C.;Dai, S.;Dupont-Nivet, G.;Krijgsman, W.;Reitsma, M.;Erens, V.
通讯作者：
Erens, V.
DOI：
--
发表时间：
2005
期刊：
2008 Second International Symposium on Intelligent Information Technology Application
影响因子：
--
作者：
P. Molnar
通讯作者：
P. Molnar