Witherow Rebecca A, Lyons W Berry
School of Earth Sciences, The Ohio State University, Columbus, Ohio, USA.
Saline Syst. 2011 Oct 12;7:2. doi: 10.1186/1746-1448-7-2.
Alkaline earth elements and alkali metals (Mg, Ca, Na and K) play an important role in the geochemical evolution of saline lakes as the final brine type is defined by the abundance of these elements. The role of major ions in brine evolution has been studied in great detail, but little has been done to investigate the behaviour of minor alkali elements in these systems despite their similar chemical affinities to the major cations. We have examined three major anionic brine types, chloride, sulphate, and bicarbonate-carbonate, in fifteen lakes in North America and Antarctica to determine the geochemical behaviour of lithium, rubidium, strontium, and barium. Lithium and rubidium are largely conservative in all water types, and their concentrations are the result of long-term solute input and concentration through evaporation and/or sublimation. Strontium and barium behaviours vary with anionic brine type. Strontium can be removed in sulphate and carbonate-rich lakes by the precipitation of carbonate minerals. Barium may be removed in chloride and sulphate brines by either the precipitation of barite and perhaps biological uptake.
碱土金属和碱金属（镁、钙、钠和钾）在盐湖的地球化学演化中起着重要作用，因为最终的卤水类型是由这些元素的丰度决定的。主要离子在卤水演化中的作用已经得到了详细研究，但尽管次要碱金属元素与主要阳离子具有相似的化学亲和力，却很少有人研究这些元素在这些系统中的行为。我们研究了北美和南极洲15个湖泊中的三种主要阴离子卤水类型，即氯化物型、硫酸盐型和碳酸氢盐 - 碳酸盐型，以确定锂、铷、锶和钡的地球化学行为。锂和铷在所有水类型中基本呈保守状态，它们的浓度是长期溶质输入以及通过蒸发和/或升华进行浓缩的结果。锶和钡的行为随阴离子卤水类型而变化。在富含硫酸盐和碳酸盐的湖泊中，锶可通过碳酸盐矿物的沉淀而去除。钡可能在氯化物和硫酸盐卤水中通过重晶石沉淀以及可能的生物吸收而被去除。
