Magnetic Properties of Street Dust: A Case in Xi'an City, Shaanxi Province, China

Abstract

AbstractSystematic analysis of magnetic characteristics of the street dust from Xi'an city indicates high concentration of magnetic minerals corresponding to the high values of magnetic susceptibility (χ), anhysteretic susceptibility (χARM) and saturation isothermal remanent magnetization (SIRM). The value of χ is positively correlated to the intensity of human activity and the value of χARM and SIRM is determined by the intensity and the magnetic mineralogy. The к‐T curve and the IRM acquisition curve indicated that the samples were dominated by ferromagnetic minerals, such as magnetite and maghemite, as well as some iron, the relative concentration of the iron might be related to the variety of the human activity: the iron pollution is mainly due to the human flow rather than pure traffic pollution and metallurgical industry. From the King‐plot and the Dearing‐plot we can conclude that the most magnetic domains of the magnetic minerals are pseudo‐single domain and multidomain. Our results suggested that magnetic measurements could be used to identify the varieties and sources of pollutants in street dust, and as the potential tools for monitoring and classifying the pollution.