摘要
应用环境磁学方法,系统地研究了乌鲁木齐市和木垒县大气自然降尘所含磁性矿物的类型、晶体粒径和含量及其环境意义。结果表明:①乌鲁木齐市和木垒县降尘中铁磁性矿物含量高,其磁学特征主要受磁铁矿控制。②乌鲁木齐市降尘中磁性矿物含量高,尤其冬季降尘,而木垒县降尘中磁性矿物含量相对较低。③乌鲁木齐市降尘样品中磁性矿物的晶体颗粒较粗,磁学特征显示多畴(MD)和假单畴(PSD)颗粒的等效特性,季节差异性小;木垒县降尘样品中磁性矿物的晶体粒径较细,为单畴(SD)颗粒,季节性差异大。研究指示乌鲁木齐市人类活动过程中排放了大量的磁性矿物,并对其降尘的磁学特征产生了明显影响,冬季表现的尤为明显。
Environmental magnetic parameters were used to systematically study magnetic properties of dustfall from a typical urban area （Urumqi） and a rural area （Mori） in Xinjiang, China. The results indicate that： （1） Magnetite is the main controlling magnetic mineral in samples from the two areas, with other kinds of magnetic minerals, such as maghematite and goethite, less dominant. （2） The content of ferrimagnetic mineral in dustfall samples from Urumqi is high, especially for samples collected during winter. Compared with samples from Urumqi, the content of magnetite is lower in samples from Mori. （3） The grain size of magnetic mineral in samples from Urumqi is coarse and dominated by multi-domain and pseudo singledomain grains, while that in samples from Mori is dominated by fine single domain grains. Compared to samples from Mori, the grain size in samples from Urumqi has less seasonal variations. The contrasting magnetic property in samples from the two areas indicates that human activities induce amount of ferrimagnetic minerals and affect the magnetic property in samples from Urumqi, especially in winter.
出处
《中国沙漠》
CSCD
北大核心
2010年第3期699-705,共7页
Journal of Desert Research
基金
中国科学院"百人计划"项目(O827631002)
国家自然科学基金项目(40871090)共同资助
