中文摘要：

新疆黄土岩石磁学特征与地层性质的对应关系具有鲜明的区域特征。本文选取沙湾黄土剖面进行较为系统的岩石磁学分析。研究结果表明,沙湾剖面的磁性矿物组成与黄土高原及新疆北部其他黄土剖面相似,以亚铁磁性矿物（如磁铁矿、磁赤铁矿）为主要的载磁矿物,同时含有一定量的不完全反铁磁性矿物（如赤铁矿、针铁矿）和顺磁性矿物。假单畴（PSD）和多畴（MD）为样品的主要磁畴特征,部分土壤样品中磁性矿物磁畴状态表现为单畴（SD）。进一步分析发现,磁化率与地层对应关系较为复杂,剖面3m以上地层中的磁化率及其他相关磁学参数与成壤强度呈现正相关关系,全新世以来发育的古土壤中磁化率值较高,细颗粒磁性矿物含量也较高; 而3m之下地层中磁学参数显著表现为风力强度驱动变化模式。古风场强度的变化可能对剖面整体磁学性质具有一定的影响,成壤作用受到风动力条件的制约,主要决定了较细颗粒磁性矿物的含量变化。XARM/SIRM参数与磁化率相比对地层成壤强度的指示作用更为明显。

英文摘要：

Rock magnetism has played a key role in paleoenvironmental studies for decades and recent 30 years especially saw the rapid progress in environmental magnetic studies of the loess/paleosol sequences all over the world. Previous studies reveal that neither the pedogenic mdoel or the wind vigor model is sufficient to explain variations of magnetic susceptibility of loess from Xinjiang.For example,it has been shown that magnetic characteristics of loess deposits in Xinjiang are controlled by wind vigor model at some intervals but controlled by the pedogenic model in some other intervals.However,most of these results were archived in the Yili valley and few studies have explored magnetic characteristics of the loess deposits in the northern part of the Tianshan Mountain zone.The loess in the northern part of the Tianshan Mountain zone,with a thickness of up to 30~50m,bear important implications for understanding evolution of the Westerlies.In this study,we reported environmental magnetism results of a loess section（Shawan section）in Xia Gobi village,Dongwan town,Shawan county,Xinjiang Uygur Autonomous Region,China.The Shawan section（44°06＇N,85°47＇E; altitude 795m）,with a thickness of about 8m,is located on top of a river terrace and this section can be divided into three layers.The first one is the layer of Holocene soils（0~168cm）.The next part is the loess layer（168~580cm）,which contain a weakly developed paleosol unit（300~350cm）.The third part is paleosols（580~840cm）with a interbedded sandy loess layer（710~780cm）.Samples were collected at 2cm intervals and then pretreated in the laboratory.After that,a systematic study of environmental magnetism was conducted.We found that,like loess from the Chinese Loess Plateau,the ferrimagnetic minerals,magnetite and maghemite,dominate bulk magnetic minerals.A certain amount of incomplete antiferromagnetic minerals（such as hematite and goethite）,with a relatively high concentration in loess layer.were also found.Different from the Loess Pla