Joint inversion based on a correlation constraint utilizes a linear correlation function as a structural constraint.The linear correlation function contains a denominator,which may result in a singularity as the objec...Joint inversion based on a correlation constraint utilizes a linear correlation function as a structural constraint.The linear correlation function contains a denominator,which may result in a singularity as the objective function is optimized,leading to an unstable inversion calculation.To improve the robustness of this calculation,this paper proposes a new method in which a sinusoidal correlation function is employed as the structural constraint for joint inversion instead of the conventional linear correlation function.This structural constraint does not contain a denominator,thereby preventing a singularity.Compared with the joint inversion method based on a cross-gradient constraint,the joint inversion method based on a sinusoidal correlation constraint exhibits good performance.An application to actual data demonstrates that this method can process real data.展开更多
In this study,Shengli fault depression,Tangyuan fault basin,and northern Songliao Basin in Yitong‒Yilan fault zone of Heilongjiang province are considered the research areas for geothermal anomaly.Based on the tempera...In this study,Shengli fault depression,Tangyuan fault basin,and northern Songliao Basin in Yitong‒Yilan fault zone of Heilongjiang province are considered the research areas for geothermal anomaly.Based on the temperature of the deep thermal reservoir,the hydrothermal fl uid channel,caprock thickness,and the mode of heat transfer,which are the main factors controlling the geothermal reservoir formation,we examined geothermal resource system of the underground HDR in this area.First,we inversed the aeromagnetic data,calculated the Curie isotherm depth,analyzed the geothermal distribution characteristics,and estimated the temperature of the deep heat source.Second,we applied the controlled source audio frequency magnetotelluric(CSAMT)and magnetotelluric(MT)methods to obtain the deep electrical structure of the study area.We determined the thickness of the caprock and the hydrothermal fluid channel.Finally,we obtained the borehole geothermal steady-state temperature measurement data and water sample chemical analysis data from the logging temperature curves of 24 wells to infer the mode of heat transfer.Based on the results,we built a model of the geothermal system of the sedimentary basin in this area.The results show that the depth of Curie isotherm in the study area is 17–39 km.The resistivity of sedimentary caprock in the north of Songliao basin is low,and there exists a deep heat source,which is mainly thermal convection.In contrast,in Shengli and Tangyuan fault basins,heat conduction is dominant.Based on the geothermal system model,we conclude that the area from Daqing to Lindian in Songliao basin has a thermal-convection-dominated sedimentary basin geothermal system.Heat exchange is realized by the upwelling of mantle-derived thermal materials through fracture channels.The thick sedimentary caprock reduces the heat loss.It can be a target for sustainable development and utilization of HDR.展开更多
基金the Science Foundation of China University of Petroleum,Beijing(2462018YJRC028)the Fundamental Research Funds for the Central Universities,China Postdoctoral Science Foundation(2019M660931)+2 种基金National Natural Science Foundation of China(21908123)State Key Laboratory of Heavy Oil Processing(SKLOP 201902006)Shandong Provincial Natural Science Foundation,China(ZR2019BB048).
基金supported by the National Key Research and Development Project of China(No:2017YFC0602201)
文摘Joint inversion based on a correlation constraint utilizes a linear correlation function as a structural constraint.The linear correlation function contains a denominator,which may result in a singularity as the objective function is optimized,leading to an unstable inversion calculation.To improve the robustness of this calculation,this paper proposes a new method in which a sinusoidal correlation function is employed as the structural constraint for joint inversion instead of the conventional linear correlation function.This structural constraint does not contain a denominator,thereby preventing a singularity.Compared with the joint inversion method based on a cross-gradient constraint,the joint inversion method based on a sinusoidal correlation constraint exhibits good performance.An application to actual data demonstrates that this method can process real data.
基金the State Key Research and Development Plan.Comprehensive Airborne Geophysics Exploration System Integration and Technical Demonstration(No.2017YFC0602201)。
文摘In this study,Shengli fault depression,Tangyuan fault basin,and northern Songliao Basin in Yitong‒Yilan fault zone of Heilongjiang province are considered the research areas for geothermal anomaly.Based on the temperature of the deep thermal reservoir,the hydrothermal fl uid channel,caprock thickness,and the mode of heat transfer,which are the main factors controlling the geothermal reservoir formation,we examined geothermal resource system of the underground HDR in this area.First,we inversed the aeromagnetic data,calculated the Curie isotherm depth,analyzed the geothermal distribution characteristics,and estimated the temperature of the deep heat source.Second,we applied the controlled source audio frequency magnetotelluric(CSAMT)and magnetotelluric(MT)methods to obtain the deep electrical structure of the study area.We determined the thickness of the caprock and the hydrothermal fluid channel.Finally,we obtained the borehole geothermal steady-state temperature measurement data and water sample chemical analysis data from the logging temperature curves of 24 wells to infer the mode of heat transfer.Based on the results,we built a model of the geothermal system of the sedimentary basin in this area.The results show that the depth of Curie isotherm in the study area is 17–39 km.The resistivity of sedimentary caprock in the north of Songliao basin is low,and there exists a deep heat source,which is mainly thermal convection.In contrast,in Shengli and Tangyuan fault basins,heat conduction is dominant.Based on the geothermal system model,we conclude that the area from Daqing to Lindian in Songliao basin has a thermal-convection-dominated sedimentary basin geothermal system.Heat exchange is realized by the upwelling of mantle-derived thermal materials through fracture channels.The thick sedimentary caprock reduces the heat loss.It can be a target for sustainable development and utilization of HDR.
