Soil gas ²²²Rn concentration in northern Germany and its relationship with geological subsurface structures

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• 作者：N. Kü ; nze ; ^{nadine.kuenze@uni-hamburg.de} ; M. Koroleva ; C.-D. Reuther
• 关键词：Radon in soil gas ; Salt tectonics ; Schleswig-Holstein
• 刊名：Journal of Environmental Radioactivity
• 出版年：2013
• 出版时间：January, 2013
• 年：2013
• 卷：115
• 期：Complete
• 页码：83-96
• 全文大小：2134 K

文摘

²²²Rn in soil gas activity was measured across the margins of two active salt diapirs in Schleswig-Holstein, northern Germany, in order to reveal the impact of halokinetic processes on the soil gas signal. Soil gas and soil sampling were carried out in springtime and summer 2011. The occurrence of elevated ²²²Rn in soil gas concentrations in Schleswig-Holstein has been ascribed to radionuclide rich moraine boulder material deposits, but the contribution of subsurface structures has not been investigated so far. Reference samples were taken from a region known for its granitic moraine boulder deposits, resulting in ²²²Rn in soil gas activity of 40?kBq/m³. The values resulting from profile sampling across salt dome margins are of the order of twice the moraine boulder material reference values and exceed 100?kBq/m³. The zones of elevated concentrations are consistent throughout time despite variations in magnitude. One soil gas profile recorded in this work expands parallel to a seismic profile and reveals multiple zones of elevated ²²²Rn activities above a rising salt intrusion. The physical and chemical properties of salt have an impact on the processes influencing gas migration and surface near radionuclide accumulations. The rise of salt supports the breakup of rock components thus leading to enhanced emanation. This work provides a first approach regarding the halokinetic contribution to the ²²²Rn in soil gas occurrence and a possible theoretical model which summarizes the relevant processes was developed.