Spatial distribution of radon and thoron in the soil around active faults as a contribution to the elevated indoor radon

活动断层周围土壤中氡气和钍气的空间分布对室内氡气升高的贡献

• 批准号: 21K12228
• 负责人: Janik Miroslaw
• 金额: $ 2.66万
• 依托单位: National Institutes for Quantum Science and Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2021
• 资助国家: 日本
• 起止时间: 2021-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-21K12228/
• 关键词: radon; thoron; active fault; permeability; carbon dioxide; radon transport; radon in soil

We analysed the data from the first measurements taken near the Fugendake volcano (U1). The radon concentration was lower than expected with low variation of horizonal nor vertical distribution. We therefore chose another active fault site, with a different geological structure near Takayama city (T1). Radon (Rn) and thoron (Tn) concentrations in soil gas with an active device together with radon exhalation rate, soil permeability and CO2 were measured. Measurements of Ra and Th in the collected soil samples were carried out using HPGe detector. Bulk density and porosity of soil samples were determined. Geophysical methods combined with the standard geotechnical cone penetrometer were used to recognize the geological structure and soil characteristics of the area and locate the predicted faults positions and routes. Obtained data were prepared as an input for the radon diffusion-convection transport model.

我们分析了Fugendake火山（U1）附近的第一个测量结果中的数据。 ra的浓度低于预期的，而水平或垂直分布的变化较低。因此，我们选择了另一个主动断层站点，在高山城附近（T1）附近具有不同的地质结构。测量了带有活性装置的土壤气体中的ra（RN）和Thoron（TN）浓度，并测量ra呼气率，土壤渗透性和CO2。使用HPGE检测器对收集的土壤样品中的RA和TH进行测量。确定土壤样品的整体密度和孔隙率。地球物理方法与标准岩土锥渗透仪结合使用，以识别该区域的地质结构和土壤特征，并找到预测的断层位置和路线。准备的数据作为ra扩散 - 转向传输模型的输入准备。

项目成果

Soil as a source of indoor radon: from generation to indoor exposure

土壤作为室内氡源：从产生到室内暴露

• 发表时间: 2021
• 作者: Miroslaw Janik