中国汞的地球化学空间分布特征

20世纪80年代以来中国积累了岩石、土壤和水系沉积物中的大量可靠的汞分析数据和图件,为分析汞的地球化学空间分布特征提供了依据.从空间分布上看,从中国北部到南部,从西部到东部,土壤和水系沉积物中汞的含量背景值逐渐增高,汞在以干旱荒漠区、半干旱荒漠区、黄土地区和高寒山区为主的西部和北部呈低背景,在东部的森林沼泽区和半湿润低山丘陵区为中等背景,在南部的湿润低山丘陵区、热带雨林区和高山峡谷区为高背景,尤其在以云南东南部、贵州、广西西部、湖南西部岩溶区为中心的低温成矿域内,无论岩石、土壤还是水系沉积物,汞含量背景值达到最高.一般情况下,岩石、土壤和水系沉积物之间的汞含量具有继承性,在地理空间分布上呈明显的对栽应关系,并且土壤和水系沉积物之间的汞含量具有相近性,土壤和水系沉积物较岩石更为富集汞.

Geochemical spatial distribution of mercury in China

Abundant reliable analyzed data and maps of mercury in rocks and loose sediments have been cumulated from 1980s,which offers evidence to analyze geochemical spatial characteristics of Hg.As viewed from spatial distribution,background value of Hg in soil and sediment rises gradually from northern China to southern China,and from western China to eastern China.Value of Hg shows low background in western and northern China where is mainly arid desert or semi-arid desert,loess,high cold mountainous areas.And the value of Hg is high in eastern and southern China,especially in low-temperature mineralized area in the karst areas of southeastern Yunnan,western Guangxi,Guizhou,western Hunan,and value of Hg gets to peak whether in rocks,soils or sediments.Generally,mercury contents between rocks,soils and sediments have inheritance,which show corresponding relationship in spatial distribution,and mercury contents between soils and stream sediments are close.Meanwhile stream sediments and soils can enrich more Hg than rocks.