地球物理学报
地毬物理學報
지구물이학보
2010年
1期
156-163
,共8页
李鹏%强小科%徐新文%李续彬%孙玉芳
李鵬%彊小科%徐新文%李續彬%孫玉芳
리붕%강소과%서신문%리속빈%손옥방
西安市%道路灰尘%环境磁学
西安市%道路灰塵%環境磁學
서안시%도로회진%배경자학
Xi'an%Street dust%Environmental magnetism
西安市道路表面灰尘样品的环境磁学研究显示磁化率(χ)、非磁滞磁化率(χ_(ARM))以及饱和等温剩磁(SIRM)均比较高,表明样品中磁性矿物含量较高.其巾磁化率(χ)主要受人类活动强度影响,而非磁滞磁化率(χ_(ARM))及饱和等温剩磁(SIRM)则由人为活动强度和磁性矿物种类共同决定.κ-T曲线以及等温剩磁(IRM)获得曲线显示样品中磁铁矿和磁赤铁矿等哑铁磁性矿物占主导,并町能含有少量的单质铁,其相对含量与人类活动种类有关:与单纯的交通排放及冶金活动相比,密集的人群流动可带来更多的单质铁矿物.磁畴图谱显示磁性矿物粒径变化不大,以准单畴及多畴颗粒等粗颗粒为主,明显大于成土作用形成的磁件颗粒.综合磁性矿物含量种类以及粒径可辨别污染及污染来源,提供污染监测的磁学手段,并初步进行污染来源划分.
西安市道路錶麵灰塵樣品的環境磁學研究顯示磁化率(χ)、非磁滯磁化率(χ_(ARM))以及飽和等溫剩磁(SIRM)均比較高,錶明樣品中磁性礦物含量較高.其巾磁化率(χ)主要受人類活動彊度影響,而非磁滯磁化率(χ_(ARM))及飽和等溫剩磁(SIRM)則由人為活動彊度和磁性礦物種類共同決定.κ-T麯線以及等溫剩磁(IRM)穫得麯線顯示樣品中磁鐵礦和磁赤鐵礦等啞鐵磁性礦物佔主導,併町能含有少量的單質鐵,其相對含量與人類活動種類有關:與單純的交通排放及冶金活動相比,密集的人群流動可帶來更多的單質鐵礦物.磁疇圖譜顯示磁性礦物粒徑變化不大,以準單疇及多疇顆粒等粗顆粒為主,明顯大于成土作用形成的磁件顆粒.綜閤磁性礦物含量種類以及粒徑可辨彆汙染及汙染來源,提供汙染鑑測的磁學手段,併初步進行汙染來源劃分.
서안시도로표면회진양품적배경자학연구현시자화솔(χ)、비자체자화솔(χ_(ARM))이급포화등온잉자(SIRM)균비교고,표명양품중자성광물함량교고.기건자화솔(χ)주요수인류활동강도영향,이비자체자화솔(χ_(ARM))급포화등온잉자(SIRM)칙유인위활동강도화자성광물충류공동결정.κ-T곡선이급등온잉자(IRM)획득곡선현시양품중자철광화자적철광등아철자성광물점주도,병정능함유소량적단질철,기상대함량여인류활동충류유관:여단순적교통배방급야금활동상비,밀집적인군류동가대래경다적단질철광물.자주도보현시자성광물립경변화불대,이준단주급다주과립등조과립위주,명현대우성토작용형성적자건과립.종합자성광물함량충류이급립경가변별오염급오염래원,제공오염감측적자학수단,병초보진행오염래원화분.
The systematic analysis on the magnetic characteristics of street dust from Xi'an city indicates high concentration of magnetic minerals corresponding to the high value of the magnetic susceptibility(χ), the anhysteretic susceptibility (χ_(ARM)) and the saturation isothermal remnant magnetization(SIRM). The value of χ is positively correlated to the intensity of human activity and the value of the χ_(ARM) and the SIRM is determined by the intensity and the magnetic mineralogy. The κ-T curve and the IRM acquisition curve indicated that the sample is 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: there are more iron minerals from the human flow pollution than the pure traffic pollution and the industry. From the King-plot and the Dearing-plot we can conclude that 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.