Biogeochemical controls on arsenic: El Tatio Geyser Field, Chile

摘要：

El Tatio Geyser Field, northern Chile, hosts widespread geothermal activity, with arsenic higher than any known geothermal system (up to 0.637 mMol). Boiling springs (86℃) discharge neutral pH, Na-Cl type waters. As(Ⅲ) As(OH)3, the dominant As species in discharge waters, rapidly oxidizes to As(Ⅴ) at an estimated rate of 0.35 min-1.Fe is enriched in sinter. XAS and sequential extraction methods shows that As,predominately as As(Ⅴ) AsO2(OH)2-, sorbs to Fe complexes. Sinter As concentrations are controlled by rapid microbial As(Ⅲ) oxidation, slow As(Ⅴ) reduction, sorption to Fe-oxyhydroxides, and co-precipitation.

作者: J.T.Landrum P.C.Bennett M.A.Alsina P.A.Pastén

作者单位: University of Texas at Austin, Austin, Texas, USA Pontificia Universidad Católica de Chile, Santiago, Chile

会议类型: 国际会议

会议名称: 第十二届水-岩相互作用国际研讨会(P0roceedings of the 12th International Symposium on Water-Rock Interaction)

会议地点: 昆明

会议语种:英文

页码: 875-879

在线出版日期: 2007-07-31（万方平台首次上网日期，不代表论文的发表时间）