Soil radon measurement of high stability and sensitivity is widely applied,and in some applications,such as in uranium prospecting,^(222)Rn should be distinguished from ^(220)Rn.To meet this requirement,a practical me...Soil radon measurement of high stability and sensitivity is widely applied,and in some applications,such as in uranium prospecting,^(222)Rn should be distinguished from ^(220)Rn.To meet this requirement,a practical method based on soil radon diffusion and accumulation theory to measure soil radon by Alpha Particle Spectroscopy(α-PS)is discussed in this paper.Theα-PS measurement method can effectively overcome the effects of ^(220)Rn and its daughters (^(216)Po,^(212)Bi,^(212)Po).The system can eliminate the impact of soil radon field disturbance and non-uniformity through soil radon static diffusion.Radon daughters(^(218)Po,^(214)Po)are accumulated under the action of an electrostatic force, which not only enhances the measurement sensitivity,but also increases robustness of the measurement.Simultaneous measurement of multiple points can increase the comparability of measurement data and the measurement efficiency. Experimental data shows that the soil radon measurement method was robust.So it has wide applications such as in geological prospecting,in fissure groundwater exploration and in ground subsidence inspection.展开更多
In the exploration of the hidden Haihe fault,radon and mercury in soil gas were measured by using FG-3017 radon detector and XG-4 mercury analyzer.In this paper,based on the measurement results of 12 fault gas profile...In the exploration of the hidden Haihe fault,radon and mercury in soil gas were measured by using FG-3017 radon detector and XG-4 mercury analyzer.In this paper,based on the measurement results of 12 fault gas profiles,and integrating with the exploration results of artificial seismic prospecting,the relationship between anomalous site of fault gas and fault location is analyzed.Using the relationship between anomalous strength of fault gas and fault activity,the activity of Haihe fault is studied,thus the location and activity segmentation of the Haihe fault in Tianjin region are presented.This study shows that the method of fault gas detection can not only identify the preliminary location of fault,but also make preliminary segmentation of fault activity.The fault detected by the method of fault gas measurement is shown as a band.Through contrasting with exploration results of artificial seismic prospecting and analyzing,we find that the fault is located inside the band.According to the measurements of soil gas radon,the Haihe fault can be divided into east and west segments and the activity of the east segment of Haihe fault is stronger than that of the west segment.This is only a relative result,and it is difficult to judge whether the fault is active or not with this result.展开更多
Soil gas radon 222Rn concentration was measured at 12 location in the Al-Qassim area, using radon gas analyzer-type Alpha GUARD 2000 PRQ from Genitron Instruments (Germany). In each location four different depths were...Soil gas radon 222Rn concentration was measured at 12 location in the Al-Qassim area, using radon gas analyzer-type Alpha GUARD 2000 PRQ from Genitron Instruments (Germany). In each location four different depths were taken for soil gas measurements, staring from the ground surface. The results suggested that the largest concentration was 340 ± 22 Bq/m3 for 60cm depth at in Al-Tarfia point sample P3, and the smallest concentration was 26 ± 5 Bq/m3 for surface 0 cm depth at El-Bakria, point sample P5. The results obtained from this study indicate that the region has background radioactivity levels within the natural limits.展开更多
Radongas concentrations in soil samples were determined from depths (surface, 15, and 30) cm for nine locations in Al-Dora refinery and surrounding area using “sealed can technique” and CR-39 solid state nuclear tra...Radongas concentrations in soil samples were determined from depths (surface, 15, and 30) cm for nine locations in Al-Dora refinery and surrounding area using “sealed can technique” and CR-39 solid state nuclear track detectors. The radon concentration in surface samples ranged from 810.08 to 1380.08 Bq/m3 with an average 1137.71 Bq/m3. The radon concentration in soil at the depth 15 cm was ranged from 490.5 to 1197.52 Bq/m3 with an average 732.78 Bq/m3 and at the depth 30 cm was ranged from 362.07 to 889.53 Bq/m3 with an average 529.41 Bq/m3. The surface exhalation rate in surface soil samples ranged was 0.44, to 0.99 Bq·m-2·h-1 with average 0.61 Bq·m-2·h-1. The surface exhalation rate in soil samples at the depth 15 cm was ranged from 0.22 to 0.64 Bq·m-2·h-1 with average 0.39 Bq·m-2·h-1. The surface exhalation rate in soil samples at the depth 15 cm was ranged from 0.22 to 0.64 Bq·m-2·h-1 with average 0.39 Bq·m-2·h-1. The surface exhalation rate and the mass exhalation rate in soil samples at the depth 30 cm ranged from 0.19, to 0.48 Bq·m-2·h-1 with average 0.28 Bq·m-2·h-1. The mass exhalation rate in surface soil samples ranged from 0.09 to 0.21 Bq·kg-1·h-1 with average 0.12 Bq·kg-1·h-1. The mass exhalation rate in soil samples from depth 15 cm was ranged from 0.046 to 0.14 Bq·kg-1·h-1 with average 0.08 Bq·kg-1·h-1. The mass exhalation rate in soil samples at the depth 30 cm was ranged from 0.042 to 0.1 Bq·kg-1·h-1 with average 0.06 Bq·kg-1·h-1.展开更多
The meteorologic effects on soil radon is dealt with. The observations during a year at fixed locations show a clear pattern of seasonal variations of soil radon which is grossly lower during spring and summer, lowest...The meteorologic effects on soil radon is dealt with. The observations during a year at fixed locations show a clear pattern of seasonal variations of soil radon which is grossly lower during spring and summer, lowest in summer, and higher during autumn and winter, highest in winter. A fall of rain or snow usually brings about a steep rise of soil radon concentration. At 0℃ or so, especially below 0℃, radon values descend greatly. Besides seasonal variations, soil radon concentration also has diurnal changes, with a pattern of lower values at noon and higher values in the early morning and in the evening. From the vertical profile, an optimum depth for the measurement, which is 65-75 cm, is recognized, where the radon value is maximal and diurnal variations are minimal. At last, measures are put forward to reduce or remove meteorologic effects on soil radon in application.展开更多
Abundant data have been gathered through measurements of radon gas emission in the soil on several major active faults,such as San Andreas and Calaveras,in California,U.S.A..They show radon emissions and their spatial...Abundant data have been gathered through measurements of radon gas emission in the soil on several major active faults,such as San Andreas and Calaveras,in California,U.S.A..They show radon emissions and their spatial variations at the unlocked,locked,and creeping sections of faults with different tectonic movements.The characteristics of these variations and the role of fault gases in the research on earthquake prediction are discussed in this paper.展开更多
文摘Soil radon measurement of high stability and sensitivity is widely applied,and in some applications,such as in uranium prospecting,^(222)Rn should be distinguished from ^(220)Rn.To meet this requirement,a practical method based on soil radon diffusion and accumulation theory to measure soil radon by Alpha Particle Spectroscopy(α-PS)is discussed in this paper.Theα-PS measurement method can effectively overcome the effects of ^(220)Rn and its daughters (^(216)Po,^(212)Bi,^(212)Po).The system can eliminate the impact of soil radon field disturbance and non-uniformity through soil radon static diffusion.Radon daughters(^(218)Po,^(214)Po)are accumulated under the action of an electrostatic force, which not only enhances the measurement sensitivity,but also increases robustness of the measurement.Simultaneous measurement of multiple points can increase the comparability of measurement data and the measurement efficiency. Experimental data shows that the soil radon measurement method was robust.So it has wide applications such as in geological prospecting,in fissure groundwater exploration and in ground subsidence inspection.
基金This research was sponsored by the project of Quantitative Evaluation of Activity of the Hidden Haihe Fault in Tianjin City (Grant No. JINJI290)
文摘In the exploration of the hidden Haihe fault,radon and mercury in soil gas were measured by using FG-3017 radon detector and XG-4 mercury analyzer.In this paper,based on the measurement results of 12 fault gas profiles,and integrating with the exploration results of artificial seismic prospecting,the relationship between anomalous site of fault gas and fault location is analyzed.Using the relationship between anomalous strength of fault gas and fault activity,the activity of Haihe fault is studied,thus the location and activity segmentation of the Haihe fault in Tianjin region are presented.This study shows that the method of fault gas detection can not only identify the preliminary location of fault,but also make preliminary segmentation of fault activity.The fault detected by the method of fault gas measurement is shown as a band.Through contrasting with exploration results of artificial seismic prospecting and analyzing,we find that the fault is located inside the band.According to the measurements of soil gas radon,the Haihe fault can be divided into east and west segments and the activity of the east segment of Haihe fault is stronger than that of the west segment.This is only a relative result,and it is difficult to judge whether the fault is active or not with this result.
文摘Soil gas radon 222Rn concentration was measured at 12 location in the Al-Qassim area, using radon gas analyzer-type Alpha GUARD 2000 PRQ from Genitron Instruments (Germany). In each location four different depths were taken for soil gas measurements, staring from the ground surface. The results suggested that the largest concentration was 340 ± 22 Bq/m3 for 60cm depth at in Al-Tarfia point sample P3, and the smallest concentration was 26 ± 5 Bq/m3 for surface 0 cm depth at El-Bakria, point sample P5. The results obtained from this study indicate that the region has background radioactivity levels within the natural limits.
文摘Radongas concentrations in soil samples were determined from depths (surface, 15, and 30) cm for nine locations in Al-Dora refinery and surrounding area using “sealed can technique” and CR-39 solid state nuclear track detectors. The radon concentration in surface samples ranged from 810.08 to 1380.08 Bq/m3 with an average 1137.71 Bq/m3. The radon concentration in soil at the depth 15 cm was ranged from 490.5 to 1197.52 Bq/m3 with an average 732.78 Bq/m3 and at the depth 30 cm was ranged from 362.07 to 889.53 Bq/m3 with an average 529.41 Bq/m3. The surface exhalation rate in surface soil samples ranged was 0.44, to 0.99 Bq·m-2·h-1 with average 0.61 Bq·m-2·h-1. The surface exhalation rate in soil samples at the depth 15 cm was ranged from 0.22 to 0.64 Bq·m-2·h-1 with average 0.39 Bq·m-2·h-1. The surface exhalation rate in soil samples at the depth 15 cm was ranged from 0.22 to 0.64 Bq·m-2·h-1 with average 0.39 Bq·m-2·h-1. The surface exhalation rate and the mass exhalation rate in soil samples at the depth 30 cm ranged from 0.19, to 0.48 Bq·m-2·h-1 with average 0.28 Bq·m-2·h-1. The mass exhalation rate in surface soil samples ranged from 0.09 to 0.21 Bq·kg-1·h-1 with average 0.12 Bq·kg-1·h-1. The mass exhalation rate in soil samples from depth 15 cm was ranged from 0.046 to 0.14 Bq·kg-1·h-1 with average 0.08 Bq·kg-1·h-1. The mass exhalation rate in soil samples at the depth 30 cm was ranged from 0.042 to 0.1 Bq·kg-1·h-1 with average 0.06 Bq·kg-1·h-1.
文摘The meteorologic effects on soil radon is dealt with. The observations during a year at fixed locations show a clear pattern of seasonal variations of soil radon which is grossly lower during spring and summer, lowest in summer, and higher during autumn and winter, highest in winter. A fall of rain or snow usually brings about a steep rise of soil radon concentration. At 0℃ or so, especially below 0℃, radon values descend greatly. Besides seasonal variations, soil radon concentration also has diurnal changes, with a pattern of lower values at noon and higher values in the early morning and in the evening. From the vertical profile, an optimum depth for the measurement, which is 65-75 cm, is recognized, where the radon value is maximal and diurnal variations are minimal. At last, measures are put forward to reduce or remove meteorologic effects on soil radon in application.
文摘Abundant data have been gathered through measurements of radon gas emission in the soil on several major active faults,such as San Andreas and Calaveras,in California,U.S.A..They show radon emissions and their spatial variations at the unlocked,locked,and creeping sections of faults with different tectonic movements.The characteristics of these variations and the role of fault gases in the research on earthquake prediction are discussed in this paper.
