地面伽马能谱测量在浅覆盖区地质填图中的应用

地面伽马能谱测量作为地质填图的辅助手段用于浅覆盖区是一种新的尝试。通过野外实测剖面，分析了地面能谱测量在浅覆盖区进行地质填图的可能性，并使用圆滑处理手段束消除局部干扰，同时还分析了地面伽马能谱测量在大兴安岭地区进行岩性划分的能力，为区域地质填图提供了一种高效、轻便、快速的手段。     

水系沉积物测量在阿巴通德拉扎卡地区找矿应用

水系沉积物测量技术在马达加斯加应用较少,笔者通过在马达加斯加阿巴通德拉扎卡地区水系沉积物测量找矿勘查,探讨该方法在此类地球化学景观地区的应用效果.应用该方法,在马达加斯加阿巴通德拉扎卡地区圈定147处综合异常,通过野外1:1万地质填图和地表工程揭露,发现钛铁、镍、金等矿产,这说明水系沉积物测量方法适用于马达加斯加中部高原地区的地球化学景观条件,圈定的异常准确、有效,并可取得较好的找矿效果.水系沉积物测量方法可在马达加斯加的同类地区推广使用.     

利用航空γ能谱资料快速预测环境氡浓度

航空γ能谱测量方法是核辐射区域本地调查,区域环境中核辐射污染调查和评价的有效方法.文中不同于以往的利用航空γ能谱测量数据换算地面(1 m高)空气吸收剂量率的方法,而是运用大地-大气氡交换理论模型及氡的析出率理论,预测区域空气中氡浓度,并可计算出区域氡地质潜势.计算结果表明方法快速、高效,具有较好的实用价值.     

青岛市天然放射性环境地质调查中测量方法探讨

通过对青岛市天然放射性环境地质调查，结合地面γ能谱、土壤氡浓度、环境地表γ剂量率、室内α径迹测量和放射性地化取样分析，介绍和讨论了各种测量方法及其质量保证措施。为环境地质、放射性监测防治工作，提供了大量数据和方法论证。     

地面伽马能谱测量在我国地质填图中的初步应用

近年来,由于核技术的发展和认识的转变,地面γ能谱测量等放射性方法在我国地质填图工作中已得到广泛应用。本文介绍地面伽马能谱测量等放射性方法在我国地质填图中的作用及应用情况。     

地面伽马能谱测量应用于浅覆盖区地质填图数据预处理

地面伽马能谱测量作为地质填图的辅助手段应用于浅覆盖区是一种尝试。利用地面伽马能谱测量数据的预处理来尝试消除浅覆盖对能谱测量的影响，通过野外试验数据和实测剖面数据的分析，进行了地表植被、局部干扰、测量几何条件、Th、K元素垂直分布分析，获得了数据预处理的简单方法，经过实测剖面的对比，证明方法是可取的。     

伽马能谱测量在侵入体岩石谱系单位填图中的应用

在１：５万区域地质填图中,可利用γ能谱测量仪在现场测定各类侵入岩的Ｕ,Ｔｈ,Ｋ含量,Ｕ／Ｔｈ,Ｋ／Ｔｈ,Ｕ／Ｋ比值和γ照射量率等参数。通过对地面γ能谱测量资料与区域地质特征的综合分析,将攀枝花地区侵入体划分为１９个单元,６个超单元及一个超单元及一个超单元组合,还确认了色腰和矮郎河花岗岩为印支期,花滩花岗岩和同德闪长岩均为太古代古陆核的组成部分。     

地面综合物探方法在浅覆盖区地质填图单元的划分研究

由于浅覆盖区的特殊地貌，给区域地质填图带来一定的困难。本文依据不同岩性的磁化率和放射性元素含量差异，讨论了不同填图单元地面磁法测量与地面伽玛能谱测量曲线关系。通过实测剖面的分析，得到大兴安岭火成岩区不同填图单元磁测异常曲线与放射性异常曲线的相关关系，从而用来快速确定浅覆盖区下填图单元边界，以减少槽探工程，减轻地质人员的工作强度。     

伽马能谱测量在侵入体岩石谱系单位填图中的应用

在１∶５万区域地质填图中,可利用γ能谱测量仪在现场测定各类侵入岩的Ｕ、Ｔｈ、Ｋ含量,Ｕ／Ｔｈ、Ｋ／Ｔｈ、Ｕ／Ｋ比值和γ照射量率等参数。通过对地面γ能谱测量资料与区域地质特征的综合分析,将攀枝花地区侵入体划分为１９个单元、６个超单元及一个超单元组合。还确认了色腰和矮郎河花岗岩为印支期,花滩花岗岩和同德闪长岩均为太古代古陆核的组成部分。     

地面氡及其子体测量在新疆汉水泉地区砂岩型铀矿找矿中的应用

介绍了氡气和γ能谱测量的基本原理,通过数据常规分析和相关分析其在新疆三塘湖盆地汉水泉地区的同点测量结果,常规分析未得出砂岩型铀矿成矿有利的氡浓度异常,而相关分析共提取了11个有利于铀成矿的氡浓度异常,说明氡气和γ能谱测量结果相关分析在砂岩型铀矿找矿中预测远景区是值得借鉴的方法.     

Impact of the deeper geological basement on soil gas and indoor radon concentrations in areas of Quaternary fluvial sediments (Bohemian Massif,Czech Republic)

The relationship of soil gas radon Rn²²² and indoor radon was studied within the Quaternary fluvial sediments of the Czech Republic. The processing of data selection from the radon database of the Czech Geological Survey and indoor radon data (database of the National Radiation Protection institute) has proved the concentration dependence of radon in Quaternary fluvial sediments on deeper bedrock. The ArcGIS processing was accompanied by the field verification in five profiles, intersecting the granitoid Central Bohemian Plutonic Complex and its rim rock types. Both theoretical and experimental results show dependence of soil gas radon and indoor radon concentrations in Quaternary fluvial sediments on deeper geological basement, thus leading to the conclusion that the lateral transport of Quaternary sediments does not play such a dominant role in radon concentrations, as was thought previously. This fact will enable to determine precisely the radon index of Quaternary sediments (in the Czech radon mapping classified as an intermediate index) into three categories according to the lithology of their geological basement.     

Predicting New Hampshire indoor radon concentrations from geologic information and other covariates

 Generalized geologic province information and data on house construction were used to predict indoor radon concentrations in New Hampshire (NH). A mixed-effects regression model was used to predict the geometric mean (GM) short-term radon concentrations in 259 NH towns. Bayesian methods were used to avoid over-fitting and to minimize the effects of small sample variation within towns. Data from a random survey of short-term radon measurements, individual residence building characteristics, along with geologic unit information, and average surface radium concentration by town, were variables used in the model. Predicted town GM short-term indoor radon concentrations for detached houses with usable basements range from 34 Bq/m³ (1 pCi/l) to 558 Bq/m³ (15 pCi/l), with uncertainties of about 30%. A geologic province consisting of glacial deposits and marine sediments was associated with significantly elevated radon levels, after adjustment for radium concentration and building type. Validation and interpretation of results are discussed. Received: 20 October 1997 · Accepted: 18 May 1998     

中国高本底城市的土壤氡水平及分布

在广东珠海地区采用便携式半导体测氡仪进行了大比例尺土壤氡浓度调查,测点数469个,面积大于100km2。珠海地区地下0.6 m处的平均土壤氡浓度为55.94±58.54 kBq/m3,其中在珠海斗门的第四纪沉积物地区、沉积物和风化花岗岩混合地区,以及风化花岗岩地区的土壤氡浓度分别是7.14±8.75,37.64±25.92和151.25±196.23 kBq/m3。高氡潜势区主要分布在黑云母花岗岩、风化花岗岩地区和新的工业开发区,且表现出与当地岩性密切相关。城市化和工业化改变了原有的天然辐射背景。珠海市区的平均土壤氡浓度分别为广州、泉州和晋江市平均值的8.3倍和15倍。研究结果表明：珠海是一个氡潜势较高的区域,需要进一步开展辐射防护目的的氡测量。     

Indoor radon correlated with soil and subsoil radon potential—a case study

High indoor radon concentrations in a uranium-radium low-level area in the Eifel region, Germany, near the village of Döttingen are caused by ascending radon migration following the convection of groundwater and soil gas along pathways (fractures and faults) in the bedrock sediments of Lower Devonian age. Positive radon anomalies in the soil gas are found to coincide with the locations of houses showing the highest concentrations. These houses are older buildings without concrete foundation slabs. Normally radon concentrations in soil gas are highly correlated with the values of emanated radon calculated on the basis of radium content in the surrounding soils and rocks (diffusive radon potential). However, close to zones of tectonic fractures and faults around the maar-type volcano of Döttingen abnormally high radon concentrations, which were transported by circulating groundwater and postvolcanic exhalation of CO₂ (convective radon potential) were detected.     

广东中山地区土壤氡浓度填图研究

为了研究区域土壤氡填图的方法,利用RAD7电子测氡仪和RADON-JOK土壤气体渗透率仪在广东省中山市进行了面积为1 800 km2的测量工作,有效测点数为67个。中山市的平均土壤氡浓度为(100.41±154.64)kBq/m3;最大值和最小值分别为0.74 kBq/m3和1 199.24 kBq/m3。土壤气体渗透率测量结果表明,在风化花岗岩地区,高渗透率和中渗透率占优势;而第四纪沉积物地区大部分土壤气体渗透率较低。基于此,结合研究区土壤氡浓度和土壤气体渗透率,对研究区土壤氡风险进行了分级评价。为土壤氡风险分级的方法研究提供了有参考价值的研究实例。     

Geological and geochemical factors affecting radon concentrations in dwellings located on permeable glacial sediments—a case study from Kinsarvik,Norway

In 1996–1997, indoor radon values of more than 40,000 Bq/m³ and large seasonal and geographical variations in indoor air radon were reported from a residential area located on a highly permeable ice-marginal deposit. Geochemical analyses of bedrock, groundwater and sediments and comparisons between indoor radon values and soil radon values indicate that the indoor radon concentrations in this area are strongly affected by subterranean airflows caused by temperature differences between soil air and atmospheric air. The airflows concentrate the radon-laden soil air towards the topographic highest part of the deposit in winter and towards the topographic lowest part in summer. In areas where subterranean airflows are likely to occur, radon measurements performed both in summer and in winter provide the best estimate of annual average indoor radon concentrations, and assessments of indoor radon concentrations based on single soil gas measurements are not recommended.     

Evaluation of geodynamic activity of the Dead Sea transform fault by radon gas concentrations

Twelve radon lines of dosimeters (detectors) were placed across the Jordan Valley active fault, which is a segment of the active Dead Sea transform fault system. Each line of the dosimeters shows one or more peaks of radon anomaly concentrations. Some of these peaks prove the intersection of the fault trace with these lines in areas where the fault plane is inferred. In other lines, the peaks correspond to the arrangement of faults in areas of pull-apart basins (sag ponds) or pressure ridges, formed due to the left or right step of the fault. Sag ponds usually show low radon emanations, because they are the place for the accumulation of very fine sediments, which decreases their porosity and hence the upward migration of the radon gas. The northern part of the Jordan Valley relatively shows high radon emanation, which could be attributed to the presence of a seismic gap in the upper Jordan valley.     

氡气测量在佳木斯城市地下热水普查的应用

在佳木斯城区地下热水调查中,运用了水中氡活度浓度测量和土壤氡活度浓度测量综合方法,有效地克服了城市地热地质调查中的不利因素。通过对水中氡活度浓度及土壤氡活度浓度测量值的正态化变换以及原始氡活度浓度异常分析,明确了氡活度浓度异常对地下热水控制构造的指示作用。通过对氡活度浓度测量值的趋势分析,提取局部异常,综合各种异常信息,确定了城区地下热水的有利远景区。     

Indoor radon concentrations in relation to geology in Slovenia

For this study 330 instantaneous indoor radon concentrations were selected from the database assembled during the Slovenian National Radon Programme. A relationship was found between indoor radon concentrations, rock type, tectonic faults and age of buildings. Indoor radon concentrations were elevated in buildings that were older than 50 years and in those with a fault under foundations. When these data were eliminated, elevated indoor radon levels were found only in buildings built on limestone. Our conclusions were confirmed by using the machine learning methods: clustering and multiple regression.     

云南禄劝县皎西乡土壤氡测量在易门-罗茨隐伏断裂研究中的应用

易门-罗茨断裂带是多期活动的大规模断裂带,以易门-罗茨断裂为主断裂。在禄劝县皎西一带,断裂带控制了南北向的串珠状第四系盆地,盆地内第四纪沉积物厚数米至数十米,主要的控盆隐伏断裂位置、特征难以确定。采用地质调查与土壤氡测量相结合的方法,查明了区内控盆隐伏断裂的位置、产状、宽度等。调查结果与地貌和区域构造特征吻合较好,因此认为,土壤氡测量适用于山间盆地内隐伏活动断裂的调查。