title: [Geochemical characteristics of radon and mercury in soil gas in Lhasa, Tibet, China].
abstract: The geochemical characteristics of radon and mercury in soil gas in Lhasa and vicinity are investigated based on the measurements of Rn and Hg concentrations, and environmental quality for Rn and Hg in soil gas was evaluated by means of the index of geoaccumulation. The data of Rn and Hg of 1 579 sampling site indicate that the values of environmental-geochemical background of Rn and Hg are 7 634.9 Bq/m3, 41.5 ng/m3 with standard deviations of 2.7 Bq/m3, 2.2 ng/m3, respectively. The environmental quality for Rn in soil gas is better in the west and east parts of studied area, but becomes moderate pollution (level III) in the north part of the central area. Rn is derived from radioactive elements in granitic sediments in the intermountain basin and granite base, which are the major sources of pollution. The environmental quality for Hg in soil gas becomes gradually polluted from the suburban to the center of urban, and the highest pollution reaches level IV. The background of Hg in soil gas is mainly controlled by compositions of sediments, but the Hg pollution caused by human waste and religionary use of mercury.
authors.affiliation: Institute of Earthquake Science, China Earthquake Administration, Beijing 100036, China. zhouxiaocheng188@163.com
authors.forename: Xiao-Cheng
authors.initials: XC
authors.lastname: Zhou
authors.forename: Jian-Guo
authors.initials: JG
authors.lastname: Du
authors.forename: Chuan-Yuan
authors.initials: CY
authors.lastname: Wang
authors.forename: Zhong-Quan
authors.initials: ZQ
authors.lastname: Cao
authors.forename: Li
authors.initials: L
authors.lastname: Yi
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
mesh_terms: D004784:Environmental Monitoring; D008628:Mercury / Q000032:analysis*; D011886:Radon / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D012990:Soil Pollutants, Radioactive / Q000032:analysis*; D018609:Tibet
chemical_list: D012989:Soil Pollutants; D012990:Soil Pollutants, Radioactive; D008628:Mercury; D011886:Radon