Lehigh University, United States.
Lehigh University, United States.
Sci Total Environ. 2015 Feb 1;505:1340-9. doi: 10.1016/j.scitotenv.2014.02.013. Epub 2014 Feb 22.
Elevated arsenic (As) concentrations in groundwater and rocks have been found in crystalline and sedimentary aquifers from New England to Pennsylvania, USA. The arsenic geochemistry and water-rock interactions of the Northern Appalachian Mountains and the Newark Basin have been researched at length, however, little is known about arsenic in the Gettysburg Basin. Both the Newark and Gettysburg Basins were formed during the breakup of Pangea, sediment deposition occurred during the Triassic and lithologies are of similar depositional environment. We compile and review the work done in the Newark Basin and collect new samples in the Gettysburg Basin for comparison. The Gettysburg Basin has 18%-39% of rock samples with arsenic concentrations greater than the crustal average of 2 mg/kg, while the Newark Basin has 73% to 95% of rock samples above the crustal average. The strongest controls on arsenic in rocks of the Gettysburg Basin are the relationship between arsenic and iron and silicon concentrations while the strongest controls in the Newark Basin are the relationship between arsenic and iron and organic carbon concentrations. The groundwater arsenic concentrations follow similarly with 8-39% of water samples from the Gettysburg Basin above 10 μg/L and 24-54% of water samples from the Newark Basin above 10 μg/L. The strongest controls on arsenic in water of the Gettysburg Basin are pH, alkalinity and silicon, while the strongest controls in the Newark Basin are pH and alkalinity.
在美国的新英格兰到宾夕法尼亚州的结晶岩和沉积含水层中，已经发现了地下水和岩石中砷浓度升高的情况。北阿巴拉契亚山脉和纽瓦克盆地的砷地球化学和水岩相互作用已经进行了深入研究，但对于盖茨堡盆地的砷知之甚少。纽瓦克和盖茨堡盆地都是在泛大陆分裂期间形成的，在三叠纪时期发生了沉积物沉积，岩性也具有相似的沉积环境。我们编译并回顾了纽瓦克盆地的工作，并在盖茨堡盆地收集了新的样本进行比较。盖茨堡盆地有 18%-39%的岩石样本中砷浓度高于地壳平均值 2 毫克/千克，而纽瓦克盆地有 73%-95%的岩石样本高于地壳平均值。盖茨堡盆地岩石中砷的最强控制因素是砷与铁和硅浓度之间的关系，而纽瓦克盆地的最强控制因素是砷与铁和有机碳浓度之间的关系。地下水砷浓度也类似，盖茨堡盆地有 8%-39%的水样中砷浓度高于 10μg/L，而纽瓦克盆地有 24%-54%的水样中砷浓度高于 10μg/L。盖茨堡盆地水中砷的最强控制因素是 pH 值、碱度和硅，而纽瓦克盆地水中砷的最强控制因素是 pH 值和碱度。
