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选取位于科尔沁沙地东北缘的六户屯剖面风沙沉积物为研究对象,进行系统的磁学特征和粒度分析。结果表明:六户屯剖面磁性矿物含量较少,磁学性质主要受亚铁磁性磁铁矿控制,并含有少量赤铁矿和针铁矿,磁性矿物粒度较细,以稳定单畴和超顺磁颗粒为主。沉积物中磁性矿物的粒度分布受风力大小与成壤强度的影响,单畴颗粒相对含量随风力的增强而增加,随土壤发育程度的增强而减少,χARM/χlf和χARM/SIRM可以指示冬夏季风的相对强弱。六户屯剖面磁性矿物粒度主要受冬季风强度及其动力分选作用的控制,磁性矿物粒度与沉积物总体粒度呈反相关;但在某些层位,夏季风影响下的成土过程对其改造作用不容忽视。成壤过程中形成的超顺磁颗粒是磁化率增强的主要因素,单畴颗粒对土壤发育适宜期磁化率的增加贡献相对较弱。
Aeolian sand sediments of the Liuhuatun section located at the northeastern margin of Horqin sandy land were selected as the research object, and the systematic magnetic characteristics and grain size analysis were carried out. The results show that there are less magnetic minerals in the section of Liu Tuen Tu section, the magnetic properties are mainly controlled by ferrimagnetism magnetite, with a small amount of hematite and goethite, and the granularity of magnetic minerals is finer. Magnetic particles based. The particle size distribution of magnetic minerals in sediments is influenced by wind strength and soil-forming intensity. The relative content of single-domain particles increases with the increase of wind force and decreases with the increase of soil development degree. ΧARM / χlf and χARM / SIRM can indicate winter and summer The relative strength of the monsoon. The magnetic mineralogical size of the Liuhuatun section is mainly controlled by the winter monsoon intensity and its dynamic separation. The magnetic mineralogical size is inverselycorrelated with the overall grain size of the sediments. However, at some horizon, The role of transformation can not be ignored. The superparamagnetic particles formed during pedogenesis are the main factors that enhance the magnetic susceptibility. The contribution of monodomain particles to the susceptibility to soil magnetic susceptibility is relatively weaker.