Groundwater arsenic contamination affecting different geologic domains in India - a review: influence of geological setting, fluvial geomorphology and Quaternary stratigraphy
Groundwater arsenic contamination affecting different geologic domains in India - a review: influence of geological setting, fluvial geomorphology and Quaternary stratigraphy
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DOI：
10.1080/10934520701566744
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发表时间：
2007-10-01
影响因子：
2.1
通讯作者：
Shah, Babar A.
中科院分区：
文献类型：
--
作者：
Acharyya, Subhrangsu K.;Shah, Babar A.
地下水中的砷污染普遍存在于富含有机物质的低地孟加拉三角洲和恒河中段狭窄的根深蒂固的河道中。达莫达尔扇三角洲的局部地区和印度中部的东加尔加元古代裂谷带内的孤立地区也受到了污染。在该裂谷带中，砷在长英质岩浆岩和当地风化岩石和土壤中进一步富集砷和铁。晚第四纪地层、地貌和沉积作用影响了全新世海平面上升期间加剧的冲积层地下水砷污染。虽然喜马拉雅是恒河泛滥平原和孟加拉三角洲的主要来源，但无法确定砷的具体来源。冈瓦纳煤层和其他印度半岛岩石可能是达莫达尔扇三角洲砷的来源。含砷黄铁矿或任何砷矿物在含水层沉积物中几乎不存在。砷主要赋存于吸附在沉积物颗粒和矿物表面的水合氧化铁(HFO)上。砷和铁通过生物介导的HFO还原溶解和相应的有机质氧化释放到地下水中。
Arsenic contamination in groundwater is pervasive within lowland organic-rich Bengal Delta and narrow entrenched channels in the Middle Ganga floodplains. Local areas of Damodar fan-delta and isolated areas within the Dongargarh Proterozoic rift-zone in central India are also contaminated. In this rift-zone, arsenic is enriched in felsic magmatic rocks and weathered rocks and soils from local areas are enriched further in arsenic and iron. Late Quaternary stratigraphy, geomorphology and sedimentation have influenced groundwater arsenic contamination in alluvium that aggraded during the Holocene sea-level rise. No specific source of arsenic could be identified, although Himalaya is the main provenance for the Ganga floodplain and the Bengal Delta. Gondwana coal seams and other Peninsular Indian rocks might be sources for arsenic in the Damodar fan-delta. As-bearing pyrite or any As-mineral is nearly absent in the aquifer sediments. Arsenic mainly occurs adsorbed on hydrated-iron-oxide (HFO), which coat sediment grains and minerals. Arsenic and iron are released to groundwater by bio-mediated reductive dissolution of HFO with corresponding oxidation of organic matter.