Radon变换是压制多次波、实现地震反射波高精度成像的重要算法之一,其聚焦性的强弱会影响部分地震数据处理的效果。传统基于频率-曲率域L2范数约束的最小二乘Radon变换,受有限孔径影响,易产生剪刀状拖尾效应。而稀疏Radon变换虽通过变...Radon变换是压制多次波、实现地震反射波高精度成像的重要算法之一,其聚焦性的强弱会影响部分地震数据处理的效果。传统基于频率-曲率域L2范数约束的最小二乘Radon变换,受有限孔径影响,易产生剪刀状拖尾效应。而稀疏Radon变换虽通过变换域稀疏性假设获得了更高聚焦性的Radon域数据,但存在能量团收敛不足的问题。为此,联合地震子波与曲率方向平滑函数协同构建反褶积算子,对已有的Radon数据开展三维反褶积,基于交替方向乘子法(alternating direction method of multipliers,ADMM)的迭代求解,提出了基于三维反褶积理论的Radon域稀疏增强算法。该算法依据稀疏反演理论,通过去模糊机制在曲率维度实现能量压缩,显著提升了能量团的聚集度与分辨率。数值模拟与实测数据应用表明,相较于常规最小二乘Radon变换和时间域稀疏Radon变换,经反褶积稀疏增强处理后的Radon域能量团可辨识度得到有效提升,从而提高了多次波的识别和压制精度。展开更多
This study examines radon emissions as potential proxies for environmental change in tropical Andean ecosystems undergoing rapid glacier retreat due to climate forcing.The research was conducted in the proglacial zone...This study examines radon emissions as potential proxies for environmental change in tropical Andean ecosystems undergoing rapid glacier retreat due to climate forcing.The research was conducted in the proglacial zone of the Yana Ucsha glacier in the Peruvian Andes,where field campaigns between July and November 2023 yielded radon measurements at approximately 28-day intervals across ten monitoring sites(M1-M10).Radon flux was measured using LR115 detectors and complemented by analyses of soil texture and the topographic wetness index(TWI)to assess the influence of environmental variables.Results demonstrate that radon emissions are strongly modulated by soil moisture,which in turn is regulated by regional air temperature and glacier runoff.A significant inverse relationship was identified between radon exhalation and regional air temperature,indicating that warmer periods suppress radon release due to increased soil moisture from enhanced glacier melt.Conversely,the coldest monitoring interval(second period)exhibited markedly higher radon exhalation,reaching up to 0.45 and 0.32 Bq m^(-2)hm^(-1)at sites M1 and M4,respectively-approximately four to five times greater than the baseline range(0-0.10 Bq m^(-2)hm^(-1))observed during other periods.This pronounced temporal anomaly coincided with lower regional air temperatures,reduced glacier runoff,and drier soil conditions,highlighting strong climatic control on radon emissions.These findings suggest that ongoing glacier retreat and climate change may constrain or reduce radon emission rates in Andean proglacial environments,with important implications for environmental monitoring and ecosystem dynamics.Overall,this study provides novel insights into the interactions among cryospheric,atmospheric,and radon dynamics in the tropical Andes.展开更多
The Yuncheng Basin,located in the southern part of the Fenwei Rift,North China,exhibits obvious crust thinning(Moho uplift of 6-8 km)and shallow Curie point depth(less than 18 km)and hence holds great potential for ge...The Yuncheng Basin,located in the southern part of the Fenwei Rift,North China,exhibits obvious crust thinning(Moho uplift of 6-8 km)and shallow Curie point depth(less than 18 km)and hence holds great potential for geothermal resources.However,geothermal exploration within the Yuncheng Basin typically faces significant challenges due to civil and industrial noise from dense populations and industrial activities.To address these challenges,both Controlled-Source Audio-frequency Magnetotellurics(CSAMT)and radon measurements were employed in Baozigou village to investigate the geothermal structures and identify potential geothermal targets.The CSAMT method effectively delineated the structure of the subsurface hydrothermal system,identifying the reservoir as Paleogene sandstones and Ordovician and Cambrian limestones at elevations ranging from−800 m to−2500 m.In particular,two concealed normal faults(F_(a)and F_(b))were newly revealed by the combination of CSAMT and radon profiling;these previously undetected faults,which exhibit different scales and opposing dips,are likely to be responsible for controlling the convection of thermal water within the Basin’s subsurface hydrothermal system.Moreover,this study developed a preliminary conceptual geothermal model for the Fen River Depression within the Yuncheng Basin,which encompasses geothermal heat sources,cap rocks,reservoirs,and fluid pathways,providing valuable insights for future geothermal exploration.In conjunction with the 3D geological model constructed from CSAMT resistivity structures beneath Baozigou village,test drilling is recommended in the northwestern region of the Baozigou area to intersect the potentially deep fractured carbonates that may contain temperature-elevated geothermal water.This study establishes a good set of guidelines for future geothermal exploration in this region,indicating that high-permeability faults in the central segments of the Fen River Depression are promising targets.展开更多
Radon变换反演分辨率是其在地震资料处理中应用的关键因素.常规高分辨率Radon变换反演模型采用L_(1)范数实现稀疏正则化,其以Radon系数振幅总体大小衡量稀疏性,未能充分考虑到Radon系数振幅相对强弱,以此构建的反演方法旨在通过衰减弱...Radon变换反演分辨率是其在地震资料处理中应用的关键因素.常规高分辨率Radon变换反演模型采用L_(1)范数实现稀疏正则化,其以Radon系数振幅总体大小衡量稀疏性,未能充分考虑到Radon系数振幅相对强弱,以此构建的反演方法旨在通过衰减弱振幅来提高稀疏性,对Radon系数分辨率提高效果有限.本文提出一种以信号振幅相对大小衡量Radon系数稀疏性的尺度不变稀疏度量(Scale-Invariant Sparsity Measure,SSM)函数,并以L_(1)/L_(2)范数作为其光滑近似.针对L_(1)/L_(2)正则化的非线性,改进交替方向乘子法(Alternating Direction Method of Multipliers,ADMM)对其求解.合成数据与实际地震资料处理结果表明,该方法能够增强一次波与多次波在Radon域的分辨率,降低Radon变换的能量扩散,提高多次波压制效果;同时该方法能够较好地压制随机噪声,方法具有一定的稳健性.展开更多
The radon control mechanism of Na_(2)O·nSiO_(2)−CaCl_(2)modified soil was studied through the laboratory simulation experiment of tailing covering radon control.The radon exhalation rate(J)is negatively correlate...The radon control mechanism of Na_(2)O·nSiO_(2)−CaCl_(2)modified soil was studied through the laboratory simulation experiment of tailing covering radon control.The radon exhalation rate(J)is negatively correlated with the coverage thickness(H),and it has a non-linear relationship with the temperature.The moisture content variation rate of the covering soil significantly decreases,which helps to reduce soil damage and enhance the resistance of the covering soil to ambient temperature interference.The formation of silicic gel and C−S−H gel effectively optimizes the pore structure and permeability,reduces the diffusion and migration of radon gas in the covering soil,and the average radon exhalation rate is decreased by 1.01×10^(−2)Bq/(m^(3)·s).The research results show that the Na_(2)O·nSiO_(2)−CaCl_(2)modified covering soil can effectively improve the radon control performance of the covering soil and reduce the cost of cover treatment.展开更多
文摘Radon变换是压制多次波、实现地震反射波高精度成像的重要算法之一,其聚焦性的强弱会影响部分地震数据处理的效果。传统基于频率-曲率域L2范数约束的最小二乘Radon变换,受有限孔径影响,易产生剪刀状拖尾效应。而稀疏Radon变换虽通过变换域稀疏性假设获得了更高聚焦性的Radon域数据,但存在能量团收敛不足的问题。为此,联合地震子波与曲率方向平滑函数协同构建反褶积算子,对已有的Radon数据开展三维反褶积,基于交替方向乘子法(alternating direction method of multipliers,ADMM)的迭代求解,提出了基于三维反褶积理论的Radon域稀疏增强算法。该算法依据稀疏反演理论,通过去模糊机制在曲率维度实现能量压缩,显著提升了能量团的聚集度与分辨率。数值模拟与实测数据应用表明,相较于常规最小二乘Radon变换和时间域稀疏Radon变换,经反褶积稀疏增强处理后的Radon域能量团可辨识度得到有效提升,从而提高了多次波的识别和压制精度。
基金partially funded by the Ministerio de Relaciones Exteriores del Perú,the Vicerectorado de Investigación of PUCPthe Fondo de Apoyo para la Investigación(FAI)2024 of PUCP.
文摘This study examines radon emissions as potential proxies for environmental change in tropical Andean ecosystems undergoing rapid glacier retreat due to climate forcing.The research was conducted in the proglacial zone of the Yana Ucsha glacier in the Peruvian Andes,where field campaigns between July and November 2023 yielded radon measurements at approximately 28-day intervals across ten monitoring sites(M1-M10).Radon flux was measured using LR115 detectors and complemented by analyses of soil texture and the topographic wetness index(TWI)to assess the influence of environmental variables.Results demonstrate that radon emissions are strongly modulated by soil moisture,which in turn is regulated by regional air temperature and glacier runoff.A significant inverse relationship was identified between radon exhalation and regional air temperature,indicating that warmer periods suppress radon release due to increased soil moisture from enhanced glacier melt.Conversely,the coldest monitoring interval(second period)exhibited markedly higher radon exhalation,reaching up to 0.45 and 0.32 Bq m^(-2)hm^(-1)at sites M1 and M4,respectively-approximately four to five times greater than the baseline range(0-0.10 Bq m^(-2)hm^(-1))observed during other periods.This pronounced temporal anomaly coincided with lower regional air temperatures,reduced glacier runoff,and drier soil conditions,highlighting strong climatic control on radon emissions.These findings suggest that ongoing glacier retreat and climate change may constrain or reduce radon emission rates in Andean proglacial environments,with important implications for environmental monitoring and ecosystem dynamics.Overall,this study provides novel insights into the interactions among cryospheric,atmospheric,and radon dynamics in the tropical Andes.
基金supported by the Shanxi Province Basic Research Program(No.20210302123374)Yuncheng University Doctoral Research Initiation Fund(No.YQ-2021008)+3 种基金Excellent doctors come to Shanxi to reward scientific research projects(No.QZX-2023020)Open Fund of State Key Laboratory of Precision Geodesy(No.SKLPG2025-1-1)Joint Open Fund of the Research Platforms of School of Computer Science,China University of Geosciences,Wuhan(No.PTLH2024-B-03)Hubei Provincial Natural Science Foundation Project(No.2025AFC095).
文摘The Yuncheng Basin,located in the southern part of the Fenwei Rift,North China,exhibits obvious crust thinning(Moho uplift of 6-8 km)and shallow Curie point depth(less than 18 km)and hence holds great potential for geothermal resources.However,geothermal exploration within the Yuncheng Basin typically faces significant challenges due to civil and industrial noise from dense populations and industrial activities.To address these challenges,both Controlled-Source Audio-frequency Magnetotellurics(CSAMT)and radon measurements were employed in Baozigou village to investigate the geothermal structures and identify potential geothermal targets.The CSAMT method effectively delineated the structure of the subsurface hydrothermal system,identifying the reservoir as Paleogene sandstones and Ordovician and Cambrian limestones at elevations ranging from−800 m to−2500 m.In particular,two concealed normal faults(F_(a)and F_(b))were newly revealed by the combination of CSAMT and radon profiling;these previously undetected faults,which exhibit different scales and opposing dips,are likely to be responsible for controlling the convection of thermal water within the Basin’s subsurface hydrothermal system.Moreover,this study developed a preliminary conceptual geothermal model for the Fen River Depression within the Yuncheng Basin,which encompasses geothermal heat sources,cap rocks,reservoirs,and fluid pathways,providing valuable insights for future geothermal exploration.In conjunction with the 3D geological model constructed from CSAMT resistivity structures beneath Baozigou village,test drilling is recommended in the northwestern region of the Baozigou area to intersect the potentially deep fractured carbonates that may contain temperature-elevated geothermal water.This study establishes a good set of guidelines for future geothermal exploration in this region,indicating that high-permeability faults in the central segments of the Fen River Depression are promising targets.
文摘Radon变换反演分辨率是其在地震资料处理中应用的关键因素.常规高分辨率Radon变换反演模型采用L_(1)范数实现稀疏正则化,其以Radon系数振幅总体大小衡量稀疏性,未能充分考虑到Radon系数振幅相对强弱,以此构建的反演方法旨在通过衰减弱振幅来提高稀疏性,对Radon系数分辨率提高效果有限.本文提出一种以信号振幅相对大小衡量Radon系数稀疏性的尺度不变稀疏度量(Scale-Invariant Sparsity Measure,SSM)函数,并以L_(1)/L_(2)范数作为其光滑近似.针对L_(1)/L_(2)正则化的非线性,改进交替方向乘子法(Alternating Direction Method of Multipliers,ADMM)对其求解.合成数据与实际地震资料处理结果表明,该方法能够增强一次波与多次波在Radon域的分辨率,降低Radon变换的能量扩散,提高多次波压制效果;同时该方法能够较好地压制随机噪声,方法具有一定的稳健性.
基金supported by the National Natural Science Foundation of China(No.51174116)the National Key Research and Development Program of China(No.2023YFC3010903)the Scientific Research Project of Education Department of Hunan Province,China(No.24A0319).
文摘The radon control mechanism of Na_(2)O·nSiO_(2)−CaCl_(2)modified soil was studied through the laboratory simulation experiment of tailing covering radon control.The radon exhalation rate(J)is negatively correlated with the coverage thickness(H),and it has a non-linear relationship with the temperature.The moisture content variation rate of the covering soil significantly decreases,which helps to reduce soil damage and enhance the resistance of the covering soil to ambient temperature interference.The formation of silicic gel and C−S−H gel effectively optimizes the pore structure and permeability,reduces the diffusion and migration of radon gas in the covering soil,and the average radon exhalation rate is decreased by 1.01×10^(−2)Bq/(m^(3)·s).The research results show that the Na_(2)O·nSiO_(2)−CaCl_(2)modified covering soil can effectively improve the radon control performance of the covering soil and reduce the cost of cover treatment.