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文中对天山北麓大佛寺(DFS)风成黄土剖面进行了光释光年代学、磁化率、粒度等气候代用指标的分析。结果认为该地区黄土沉积始于6.85±0.56ka B.P.左右,属于全新世黄土。通过粒级标准偏差法从黄土中分离出两种主要的环境敏感组分,分别代表了该地区两种主要的粉尘风力搬运与沉积系统。它们在时间轴线上的变化则代表了区域大气环流与气候模式的小幅度调整。研究结果还表明,该地区自黄土沉积以来就处于干旱状态,小幅度降水及气温的变化对黄土的影响极为有限,堆积的粉尘对黄土的理化性质才具有决定性的作用。
In this paper, the paleo-luminescence chronology, magnetic susceptibility, grain size and other climate proxy indicators are analyzed for the aeolian loess section of DFS at DFS. The results show that the loess sediments in this area began around 6.85 ± 0.56ka B.P., belonging to the Holocene loess. Two major environmentally sensitive components were isolated from loess by the grain-size standard deviation method, representing the two main dust wind handling and deposition systems in the area. Their changes in the time axis represent a small adjustment of regional atmospheric circulation and climate models. The results also show that the area has been in aridity since the deposition of loess, and the influence of slight precipitation and temperature changes on loess is extremely limited. The accumulated dust has a decisive effect on the physicochemical properties of loess.