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Hydrodynamic resistance of pore–throat structures and its effect on shale oil apparent permeability
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作者 Wendong Wang Qian Zhang +3 位作者 Jilong Xu Da Zheng Lifeng Liu Yuliang Su 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期101-110,共10页
Oil transport is greatly affected by heterogeneous pore–throat structures present in shale.It is therefore very important to accurately characterize pore–throat structures.Additionally,it remains unclear how pore–t... Oil transport is greatly affected by heterogeneous pore–throat structures present in shale.It is therefore very important to accurately characterize pore–throat structures.Additionally,it remains unclear how pore–throat structures affect oil transport capacity.In this paper,using finite element(FE)simulation and mathematical modeling,we calculated the hydrodynamic resistance for four pore–throat structure.In addition,the influence of pore throat structure on shale oil permeability is analyzed.According to the results,the hydrodynamic resistance of different pore throat structures can vary by 300%.The contribution of additional resistance caused by streamline bending is also in excess of 40%,even without slip length.Fur-thermore,Pore–throat structures can affect apparent permeability by more than 60%on the REV scale,and this influence increases with heterogeneity of pore size distribution,organic matter content,and organic matter number.Clearly,modeling shale oil flow requires consideration of porous–throat structure and additional resistance,otherwise oil recovery and flow capacity may be overestimated. 展开更多
关键词 Pore–throat structure Hydrodynamic resistance apparent permeability REV-scale Shale oil
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Identification of watered-out zones in carbonate reservoirs using resistivity curve reconstruction based on reservoir classification
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作者 Fei Wang Lun Zhao +2 位作者 Huiyuan Bian Chengqian Tan Jianxin Li 《Energy Geoscience》 2023年第2期128-134,共7页
The KT-II layer in the Zananor Oilfield,Caspian Basin,Kazakhstan,contains carbonate reservoirs of various types.The complex pore structure of the reservoirs have made it difficult to identify watered-out zones with tr... The KT-II layer in the Zananor Oilfield,Caspian Basin,Kazakhstan,contains carbonate reservoirs of various types.The complex pore structure of the reservoirs have made it difficult to identify watered-out zones with traditional logging interpretation methods.This study classifies the reservoirs on the basis of core analysis and establishes an identification model for watered-out layers in the field to effectively improve the interpretation accuracy.Thin section analysis shows that there are three types of pores in the reservoirs,i.e.,the matrix pore,fracture and dissolution vug.A triple porosity model is used to calculate the porosities of the reservoirs and the results are combined with core analysis to classify the reservoirs into the fractured,matrix pore,fracture-pore as well as composite types.A classification standard is also proposed.There are differences in resistivity logging responses from the reservoirs of different types before and after watering-out.The preewatering-out resistivities are reconstructed using generalized neural network for different types of reservoirs.The watered-out layers can be effectively identified according to the difference in resistivity curves before and after watering-out.The results show that the watered-out layers identified with the method are consistent with measured data,thus serving as a reference for the evaluation of watered-out layers in the study area. 展开更多
关键词 Watered-out zone Reconstructed resistivity Neural network Log evaluation Reservoir classification
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The Effects of Negative Values of Apparent Resistivity in TEM Surveys 被引量:1
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作者 Cassiano Antonio Bortolozo Julian David Realpe Campaña +2 位作者 Marco Antonio Couto Junior Jorge Luis Porsani Fernando Acácio Monteiro dos Santos 《International Journal of Geosciences》 2016年第10期1182-1190,共9页
The calculation of apparent resistivity in electrical methods is relatively simple and consolidated in the literature. Furthermore, in the case of DC methods, the apparent resistivity values are for the most part, int... The calculation of apparent resistivity in electrical methods is relatively simple and consolidated in the literature. Furthermore, in the case of DC methods, the apparent resistivity values are for the most part, intuitive and enable an initial interpretation of the results. On the other hand, in TEM method the apparent resistivity values are not very intuitive and interpretation based only on the apparent resistivity values cannot be done reasonably. In this way, this paper presents a discussion about the reasons and effects of the negatives values of apparent resistivity in TEM soundings. The main objective of this paper is to clarify the meanings of these negatives values and the possible effects in TEM inversion. 展开更多
关键词 Transient Electromagnetic (TEM) apparent resistivity Negative Values
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Identification and Evaluation of Low Resistivity Pay Zones by Well Logs and the Petrophysical Research in China 被引量:3
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作者 Mao Zhiqiang Kuang Lichun +3 位作者 Xiao Chengwen Li Guoxin Zhou Cancan Ouyang Jian 《Petroleum Science》 SCIE CAS CSCD 2007年第1期41-48,共8页
This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log ... This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log response of the low resistivity pay zones discovered and evaluated in recent years, as well as the problems in recognizing and evaluating low resistivity pay zones by well logs. The research areas mainly include the Neogene formations in the Bohai Bay Basin, the Triassic formations in the northern Tarim Basin and the Cretaceous formations in the Junggar Basin, The petrophysical research concerning recognition and evaluation of the low resistivity pays, based on their genetic types, is introduced in this paper. 展开更多
关键词 Low-resistivity pay zone in China origin and type petrophysical research identification and evaluation by well logs
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Analysis on Apparent Resistivity Variations of Garzê Station before the 2013 Lushan M_S 7. 0 Earthquake
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作者 Xie Tao Lu Jun +1 位作者 Ren Yuexia Zhao Minyuan 《Earthquake Research in China》 2014年第3期388-402,共15页
A trend increase in apparent resistivity has been observed in the N30°E monitoring direction at Garze Seismic Station since July 2011. This increase trend in geo-electric resistivity has been observed in the N60&... A trend increase in apparent resistivity has been observed in the N30°E monitoring direction at Garze Seismic Station since July 2011. This increase trend in geo-electric resistivity has been observed in the N60°W direction since 2012. During the period of the increase, the national highway No.317 was expanded in the monitoring area, so the potential electrodes in the N30°E direction had to be moved 10m towards the current electrodes. We interpreted the electric sounding data of Garz6 Seismic Station with a horizontally layered model. Analysis based on this model showed that the shift of potential electrodes can cause a 4 l-l.m rise to the measurements in the N30°E direction. Therefore, apparent resistivity of the two directions increased in the same time in 2012 after offsetting the effects from electrodes shift. Sensitivity coefficients of the two observation directions were also obtained using the model. Sensitivity coefficients of both directions were negative for the shallow layers, which can well explain the unexpected annual variations of Garze Seismic Station. In order to quantitatively analyze the effects from the expansion of the national highway on the observation, we constructed a finite element model based on the electrical structure. Analysis results also suggested that the expansion of the national highway could only cause a 0. 15 Ω·m decrease in the N60°W monitoring direction and 0. 1 Ω· m increase in the N30°E direction. Additionally, the valley values of annual variation of 2013 were distinctively higher than that of other years since 2008, meaning that there was an abnormal rise in apparent resistivity in the two observation directions at Garz~ Seismic Station before the Lushan earthquake. However, the rise was contrary to the decline variation before the Wenchuan earthquake. Therefore, it is still unsure whether or not the rise variation is related to the Lushan earthquake. 展开更多
关键词 Lushan earthquake Garze Seismic Station apparent resistivity Trendincrease Annual variation
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Pharmacoepidemiologic study of association between apparent treatment resistant hypertension, cardiovascular disease and interaction effect by sex and age 被引量:1
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作者 Julianne Theresa Nelson Longjian Liu 《World Journal of Cardiology》 2023年第5期262-272,共11页
BACKGROUND A limited number of studies have been conducted to test the magnitudes of the association between apparent treatment resistant hypertension(aTRH)and risk of cardiovascular disease(CVD).AIM To investigate th... BACKGROUND A limited number of studies have been conducted to test the magnitudes of the association between apparent treatment resistant hypertension(aTRH)and risk of cardiovascular disease(CVD).AIM To investigate the association between aTRH and risk of CVD and examine whether sex and age modify this association.METHODS We applied an observational analysis study design using data from the United States Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial(ALLHAT).ALLHAT recruited participants(n=25516)from 625 primary care settings throughout the United States,Canada,Puerto Rico,and United States Virgin Islands,aged 55 and older with hypertension and at least one additional risk factor for heart disease.aTRH was assessed from the year 2 visit.CVD event was defined as one of the following from the year 2 follow-up visit:Fatal or non-fatal myocardial infarction,coronary revascularization,angina,stroke,heart failure,or peripheral artery disease.Cox proportional hazards regression was used to examine the effect of aTRH on CVD risk.Potential modifications of sex and age on this association were examined on the multiplicative scale by interaction term and additive scale by joint effects and relative excess risk for interaction.RESULTS Of the total study participants(n=25516),5030 experienced a CVD event during a mean of 4.7 years follow-up.aTRH was associated with a 30%increase in risk of CVD compared to non-aTRH[hazards ratio(HR)=1.3,95%CI:1.19-1.42].Sex and age modified this relationship on both multiplicative and additive scales independently.Stratified by sex,aTRH was associated with a 64%increase in risk of CVD(HR=1.64,95%CI:1.43–1.88)in women,and a 13%increase in risk of CVD(HR=1.13,95%CI:1.01–1.27)in men.Stratified by age,aTRH had a stronger impact on the risk of CVD in participants aged<65(HR=1.53,95%CI:1.32–1.77)than it did in those aged≥65(HR=1.18,95%CI:1.05–1.32).Significant two-way interactions of sex and aTRH,and age and aTRH on risk of CVD were observed(P<0.05).The observed joint effect of aTRH and ages≥65 years(HR=1.85,95%CI:1.22–2.48)in males was less than what was expected for both additive and multiplicative models(HR=4.10,95%CI:3.63–4.57 and 4.88,95%CI:3.66–6.31),although three-way interaction of sex,age,and aTRH on the risk of CVD and coronary heart disease did not reach a statistical significance(P>0.05).CONCLUSION aTRH was significantly associated with an increased risk of CVD and this association was modified by both sex and age.Further studies are warranted to test these mechanisms. 展开更多
关键词 apparent treatment resistant hypertension Cardiovascular disease outcomes Chronic kidney disease SEX Age
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Genetic progress in stem lodging resistance of the dominant wheat cultivars adapted to Yellow-Huai River Valleys Winter Wheat Zone in China since 1964 被引量:10
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作者 ZHANG Hong-jun LI Teng +9 位作者 LIU Hong-wei MAI Chun-yan YU Guang-jun LI Hui-li YU Li-qiang MENG Ling-zhi JIAN Da-wei YANG Li LI Hong-jie ZHOU Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第2期438-448,共11页
Analysis of genetic progress for lodging-related traits provides important information for further improvement of lodging resistance.Forty winter wheat cultivars widely grown in the Yellow-Huai River Valleys Winter Wh... Analysis of genetic progress for lodging-related traits provides important information for further improvement of lodging resistance.Forty winter wheat cultivars widely grown in the Yellow-Huai River Valleys Winter Wheat Zone(YHWZ)of China during the period of 1964–2015 were evaluated for several lodging-related traits in three cropping seasons.Plant height,height at center of gravity,length of the basal second internode,and lodging index decreased significantly in this period,and the average annual genetic gains for these traits were–0.50 cm or–0.62%,–0.27 cm or–0.60%,–0.06 cm or–0.63%,and–0.01 or–0.94%,respectively.Different from other traits,stem strength showed a significant increasing trend with the breeding period,and the annual genetic gains were 0.03 N or 0.05%.Correlation analysis showed that lodging index was positively correlated with plant height,height at center of gravity,and length of the basal second internode,but negatively correlated with stem strength.Meanwhile,significantly positive correlations were observed between plant height,height at center of gravity,and length of the basal first and second internodes.By comparison with the wild types,dwarfing genes had significant effects on all lodging-related traits studied except for length of the basal first internode and stem strength.Principle component analysis demonstrated that plant height and stem strength were the most important factors influencing lodging resistance.Clustering analysis based on the first two principle components further indicated the targets of wheat lodging-resistant breeding have changed from reducing plant height to strengthening stem strength over the breeding periods.This study indicates that the increase of stem strength is vital to improve lodging resistance in this region under the high-yielding condition when plant height is in an optimal range. 展开更多
关键词 Triticum aestivum lodging resistance stem strength genetic progress Yellow-Huai River Valleys Winter Wheat zone
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Deep Seismogenic Environment in the Southern Section of the Longmenshan Fault Zone on the Eastern Margin of the Tibetan Plateau and Lushan M_s 7.0 Earthquake 被引量:4
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作者 LI Dahu DING Zhifeng +2 位作者 ZHAN Yan WU Pingping YE Qingdong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第2期519-530,共12页
The 2,026 earthquake events registered by the Sichuan regional digital seismic network and mobile seismic array after the April 20th, 2013 Lushan earthquake and 28,188 pieces of data were selected to determine direct ... The 2,026 earthquake events registered by the Sichuan regional digital seismic network and mobile seismic array after the April 20th, 2013 Lushan earthquake and 28,188 pieces of data were selected to determine direct P waves arrival times. We applied the tomographic method to inverse the characteristics of the velocity structure for the three-dimensional (3D) P wave in the mid-upper crust of the seismic source region of the Lushan earthquake. The imaging results were combined with the apparent magnetization inversion and magnetotelluric (MT) sounding retest data to comprehensively study the causes of the deep seismogenic environment in the southern section of the Longmenshan fault zone and explore the formation of the Lushan earthquake. Research has shown that there are obvious differences in velocity structure and magnetic distribution between the southern and northern sections of the Longmenshan fault zone. The epicenter of the Lushan earthquake is located near the boundary of the high and low-velocity anomalies and favorable for a high-velocity section. Moreover, at the epicenter of the Lushan earthquake located on the magnetic dome boundary of Ya'an, the development of high velocity and magnetic solid medium favors the accumulation and release of strain energy. Low- velocity anomalies are distributed underneath the are of seismogenic origin, The inversion results of the MT retest data after the April 20th Lushan earthquake also indicate that there a high-conductor anomaly occurs under the area of seismogenic origin of the Lushan earthquake, Therefore, we speculated that the presence of a high-conductivity anomaly and low-velocity anomaly underneath the seismogenic body of the Lushan earthquake could be related to the existence of fluids. The role of fluids caused the weakening of the seismogenic layer inside the mid-upper crust and resulted in a seismogenic fault that was prone to rupture and pIayed a triggering role in the Lushan earthquake. 展开更多
关键词 the Longmenshan fault zone Lushan earthquake the three-dimensional velocitystructure the apparent magnetization inversion magnetotelluric sounding
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Research of the electrical anisotropic characteristics of water-conducting fractured zones in coal seams 被引量:7
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作者 Su Ben-Yu Yue Jian-Hua 《Applied Geophysics》 SCIE CSCD 2017年第2期216-224,322,共10页
Water flooding disasters are one of the five natural coal-mining disasters that threaten the lives of coal miners. The main causes of this flooding are water-conducting fractured zones within coal seams. However, when... Water flooding disasters are one of the five natural coal-mining disasters that threaten the lives of coal miners. The main causes of this flooding are water-conducting fractured zones within coal seams. However, when resistivity methods are used to detect water-conducting fractured zones in coal seams, incorrect conclusions can be drawn because of electrical anisotropy within the water-conducting fractured zones. We present, in this paper, a new geo-electrical model based on the geology of water-conducting fractured zones in coal seams. Factors that influence electrical anisotropy were analyzed, including formation water resistivity, porosity, fracture density, and fracture surface roughness, pressure, and dip angle. Numerical simulation was used to evaluate the proposed electrical method. The results demonstrate a closed relationship between the shape of apparent resistivity and the strike and dip of a fracture. Hence, the findings of this paper provide a practical resistivity method for coal-mining production. 展开更多
关键词 water-conducting fractured zones in coal seams coalfield goaf electrical anisotropy surface roughness formation water resistivity formation pressure
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Calculation of all-time apparent resistivity of large loop transient electromagnetic method with very fast simulated annealing 被引量:4
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作者 李建慧 朱自强 +2 位作者 冯德山 肖建平 彭凌星 《Journal of Central South University》 SCIE EI CAS 2011年第4期1235-1239,共5页
In large loop transient electromagnetic method(TEM),the late time apparent resistivity formula cannot truly reflect the geoelectric model,thus it needs to define the all-time apparent resistivity with the position inf... In large loop transient electromagnetic method(TEM),the late time apparent resistivity formula cannot truly reflect the geoelectric model,thus it needs to define the all-time apparent resistivity with the position information of measuring point.Utilizing very fast simulated annealing(VFSA) to fit the theoretical electromagnetic force(EMF) and measured EMF could obtain the all-time apparent resistivity of the measuring points in rectangular transmitting loop.The selective cope of initial model of VFSA could be confirmed by taking the late time apparent resistivity of transient electromagnetic method as the prior information.For verifying the correctness,the all-time apparent resistivities of the geoelectric models were calculated by VFSA and dichotomy,respectively.The results indicate that the relative differences of apparent resistivities calculated by these two methods are within 3%.The change of measuring point position has little influence on the tracing pattern of all-time apparent resistivity.The first branch of the curve of all-time apparent resistivity is close to the resistivity of the first layer medium and the last branch is close to the resistivity of the last layer medium,which proves the correctness of the arithmetics proposed. 展开更多
关键词 very fast simulated annealing (VFSA) large loop transient electromagnetic method rectangular loop all-time apparent resistivity
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AN EFFICIENT NUMERICAL MODELING OF THE DC RESISTIVITY LOGGING: THEORY AND APPLICATIONS 被引量:1
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作者 Nie Zaiping Yang Fong Nie Xiaochuen Yuan Ning Cheng Shiyuan(University of Electronic Science and Technology of China, Chengdu 610054) 《Journal of Electronics(China)》 1997年第2期169-179,共11页
The numerical solution of Green’s function for the potential in 2-D arbitrary in-homogeneous media with axial symmetry has been given by use of efficient half-analytical, half-numerical hybrid method. Then the loggin... The numerical solution of Green’s function for the potential in 2-D arbitrary in-homogeneous media with axial symmetry has been given by use of efficient half-analytical, half-numerical hybrid method. Then the logging responses of various kinds of the DC resistivity log with axisymmetric excitation have been obtained by using surface integral equation method to match the boundary conditions on the electrodes of the logging sonde. Comparing the results with that obtained by other methods, one can see good precision and efficiency of the given method. Some applications of the numerical modeling have been also discussed. 展开更多
关键词 DC resistivity LOGGING apparent resistivity response NUMERICAL modeling
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Apparent resistivity of azimuthal anisotropy layered media
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作者 阮爱国 毛桐恩 +1 位作者 李清河 葛双成 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2002年第5期526-532,共7页
The electric field, equations of boundary conditions and calculation formula of apparent resistivity are derived for the azimuthal anisotropy layered media with the DC method based on the anisotropic Ohm's law. Ta... The electric field, equations of boundary conditions and calculation formula of apparent resistivity are derived for the azimuthal anisotropy layered media with the DC method based on the anisotropic Ohm's law. Taking the Schlumberger symmetric system as an example and using the recurrence formula of nuclear function, the paper theoretically simulates a model of four layers with the same anisotropy coefficient for each layer. The deep sounding curves of resistivity and the pattern of contours are obtained for the model. The results show that the theoretical formula is correct, and the deep sounding curves not only exhibit the difference of resistivity among layers but also indicate the anisotropy characteristics of layers. 展开更多
关键词 layered media azimuthal anisotropy apparent resistivity
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Magnetotelluric Constraints on the Occurrence of Lower Crustal Earthquakes in the Intra-plate Setting of Central Indian Tectonic Zone
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作者 K.K.ABDUL AZEEZ 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第3期884-899,共16页
Lower crustal earthquake occurrence in the Central Indian Tectonic Zone (CITZ) of the Indian sub-continent was investigated using magnetotelluric (MT) data. MT models across the CITZ, including the new resistivity... Lower crustal earthquake occurrence in the Central Indian Tectonic Zone (CITZ) of the Indian sub-continent was investigated using magnetotelluric (MT) data. MT models across the CITZ, including the new resistivity model across the 1938 Satpura lower crustal earthquake epicenter, show low resistive (〈80 Ωm) mid-lower crust and infer small volume (〈1 vol%) of aqueous fluids existing in most part of lower crust. This in conjunction with xenoliths and other geophysical data supports a predominant brittle/semi-brittle lower crustal theology. However, the local deep crustal zones with higher fluid content of 2.2%-6.5% which have been mapped imply high pore pressure conditions. The observation above and the significant strain rate in the region provide favorable conditions (strong/ moderate rock strength, moderate temperature, high pore pressure and high strain rate) for brittle failure in the lower crust. It can be inferred that the fluid-rich pockets in the mid-lower crust might have catalyzed earthquake generation by acting as the source of local stress (fluid pressure), which together with the regional stress produced critical seismogenic stress conditions. Alternatively, fluids reduce the shear strength of the rocks to favor tectonic stress concentration that can be transferred to seismogenic faults to trigger earthquakes. 展开更多
关键词 resistivity fluids lower crustal earthquake intra-plate Central Indian Tectonic zone
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Resistivity is used as a tool to evaluate the variability of soil water content
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作者 ZHANG Bin ZHANG Mao-sheng +2 位作者 SUN Ping-ping LIU Hao FENG Li 《Journal of Mountain Science》 SCIE CSCD 2022年第12期3533-3547,共15页
Resistivity is used to evaluate soil water content(SWC),which has the advantages of not causing soil disturbance and in low price.It is an effective way to assess the SWC variability.This paper aims to evaluate the va... Resistivity is used to evaluate soil water content(SWC),which has the advantages of not causing soil disturbance and in low price.It is an effective way to assess the SWC variability.This paper aims to evaluate the variability of loess slope SWC through the change of resistivity.It provides a simple way for long term SWC monitoring to solve the expensive cost of deploying moisture sensors.In this context,geoelectric and environmental factors such as soil temperature and SWC were monitored for three years.The prediction model of apparent resistivity and SWC was calibrated.The post processing of geoelectric data was introduced.In addition,the SWC collected by Time-Domain Reflectometry(TDR)was used to verify the feasibility of electrical resistivity tomography(ERT)data.The SWC variability in the process of rainfall,the evolution of four seasons,and the alternation of drying and wetting were evaluated.The research results show that:i)the SWC monitored by ERT and TDR can reflect the response and hysteretic effect of water content at 0.5-3.0 m depth.ii)The moisture content monitored by ERT reflects that the soil is relatively wet in summer and autumn and dry in winter and spring.iii)From 2017 to 2020,the SWC increased in August,and the soil became dry in January.iv)Two areas with high SWC and three areas with low SWC on loess slope are reflected by resistivity.The outcome can provide the change information of SWC to a great extent without excavating boreholes. 展开更多
关键词 Loess slope RAINFALL Prediction model Moisture variability apparent resistivity Soil water content
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A new approach for calculating the apparent resistivity tensor
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作者 Zhou Cong Tang Jing-Tian +2 位作者 Yuan Yuan Ren Zheng-Yong Li Yong 《Applied Geophysics》 SCIE CSCD 2021年第3期386-395,433,434,共12页
The apparent resistivity tensor pB is an electromagnetic transfer function,which can be used to analyze and explain the underground electrical structure.Conventional method for obtaining the parameter requires control... The apparent resistivity tensor pB is an electromagnetic transfer function,which can be used to analyze and explain the underground electrical structure.Conventional method for obtaining the parameter requires controlled sources and can be easy to be disturbed by cultural noises.We present a new method for calculating the apparent resistivity tensor,the current density is first obtained by measuring the curl operator of the magnetic field on the Earth's surface.This approach is independent of the assumption of a plane wave,and may be used irrespective of source types and field areas.We derived the analytical expressions of the apparent resistivity tensor based on synthetic horizontally layered models with a vertical magnetic dipole source.We then calculate the responses of Pb through numerical modeling examples using both natural sources and controlled sources.Compared to traditional apparent resistivity definitions,our apparent resistivity tensor has the same amplitude value but with more sensitive phases in the far zone,and shows few distortions in the transition zone.And in the near-field zone,it is closer to the resistivity distribution under the ground.The simulation results have demonstrated the effectiveness of the proposed method for calculating the apparent resistivity tensor. 展开更多
关键词 apparent resistivity tensor curl of magnetic field CSAMT numerical modeling nonplanar wave
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Characterisation of Fractures and Fracture Zones in a Carbonate Aquifer Using Electrical Resistivity Tomography and Pricking Probe Methodes
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作者 Sándor Szalai Attila Kovács +4 位作者 Lukács Kuslits Gábor Facskó Katalin Gribovszki János Kalmár László Szarka 《Journal of Geoscience and Environment Protection》 2018年第4期1-21,共21页
Position, width and fragmentation level of fracture zones and position, sig-nificance and characteristic distance of fractures were aimed to determine in a carbonate aquifer. These are fundamental parameters, e.g. in ... Position, width and fragmentation level of fracture zones and position, sig-nificance and characteristic distance of fractures were aimed to determine in a carbonate aquifer. These are fundamental parameters, e.g. in hydrogeological modelling of aquifers, due to their role in subsurface water movements. The description of small scale fracture systems is however a challenging task. In the test area (Kádárta, Bakony Mts, Hungary), two methods proved to be applicable to get reasonable information about the fractures: Electrical Resistivity Tomography (ERT) and Pricking-Probe (PriP). PriP is a simple mechanical tool which has been successfully applied in archaeological investigations. ERT results demonstrated its applicability in this small scale fracture study. PriP proved to be a good verification tool both for fracture zone mapping and detecting fractures, but in certain areas, it produced different results than the ERT. The applicability of this method has therefore to be tested yet, although its problems most probably origin from human activity which reorganises the near-surface debris distribution. In the test site, both methods displayed fracture zones including a very characteristic one and a number of individual fractures and determined their characteristic distance and significance. Both methods prove to be able to produce hydrogeologically important parameters even individually, but their simultaneous application is recommended to decrease the possible discrepancies. 展开更多
关键词 KARST FRACTURE FRACTURE zone Electrical resistivity TOMOGRAPHY Pricking Probe
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On the Origin of Crustal High Conductivity Zone in theWestern Tibet Plateau
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作者 GU Jiangfan DONG Hao +6 位作者 JIN Sheng WEI Wenbo YE Gaofeng ZHANG Letian JIN Jianen XIE Chengliang YIN Yaotian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第S01期34-36,共3页
The subduction of the Indian continental lithosphere under the Asian continent caused the uplift of the Tibet Plateau,resulting in the formation of a thickened continental crust twice of the normal value and the crust... The subduction of the Indian continental lithosphere under the Asian continent caused the uplift of the Tibet Plateau,resulting in the formation of a thickened continental crust twice of the normal value and the crustal shortening of at least 1500 km.Therefore,many models have been proposed to explain the shortening and material transportation mechanism of the Tibetan Plateau. 展开更多
关键词 three-dimensional resistivity model high conductivity zone West Tibet plateau
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Tectonic Control of the Theistareykir Geothermal Field by Rift and Transform Zones in North Iceland:A Multidisciplinary Approach
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作者 Maryam Khodayar Sveinbjorn Bjornsson +3 位作者 Sigurour Garoar Kristinsson Ragna Karlsdóttir Magnús Olafsson Skúli Víkingsson 《Open Journal of Geology》 2018年第6期543-584,共42页
This paper presents a multidisciplinary structural analysis of a 165 km2 area in the Northern Rift Zone and the Tj&#246;rnes Fracture Zone of Iceland, and unravels the tectonic control of the Theistareykir geother... This paper presents a multidisciplinary structural analysis of a 165 km2 area in the Northern Rift Zone and the Tj&#246;rnes Fracture Zone of Iceland, and unravels the tectonic control of the Theistareykir geothermal field and its surroundings. About 10729 fracture segments (faults, open fractures, joints) are identified in the upper Tertiary to Holocene igneous series. The segments were extracted from aerial images and hillshade, and then analyzed in terms of number of sets, geometry, motions, frequency, and relative age. The correlation with surface geothermal manifestations, resistivity, earthquakes, and occasional well data reveals the critical regional and local fractures at the surface, reservoir level and greater depth. The main conclusions of this study are: 1) The structural pattern consists of N-S rift-parallel extensional fractures and the Riedel shears of the transform zone striking NNE, ENE, E-W, WNW and NW, which compartmentalize together the blocks at any scale. 2) The en échelon segmentation shows strike and oblique slips on the Riedel shears, with a dextral component on the WNW and NW planes and a sinistral component on the NNE to ENE faults. 3) Fractures form under the influence of the transform mechanism and the effect of rifting becomes significant only with time. 4) The WNW dextral oblique-slip Stórihver Fault of the transform zone has a horsetail splay that extends eastwards into the geothermal field. There, this structure, along with few NW, ENE, NNE and N-S fractures, controls the alteration, alignment of fumaroles, emanating deep gases. These fractures also rupture during natural or induced earthquakes. 5) The resistivity anomalies present en échelon geometries controlled by the six fracture sets. These anomalies display clockwise and anticlockwise rotations within the upper 8 km crustal depth, but at 8 km depth, only three sets (the N-S rift structures, and the E-W and the NW Riedel shears) are present at the rift and transform plate boundaries. Results of this study are relevant to resource exploration in other complex extensional contexts where rift and transform interact.&#246;&#246;&#246; 展开更多
关键词 Northern Rift zone of Iceland Tjornes Transform zone Tectonic Control of Geothermal Activity Fractured Reservoir EARTHQUAKES resistivity Anomalies
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Resistant Evaluation of Kiwifruit Rootstocks to Root Zone Hypoxia Stress 被引量:7
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作者 Yinfa Mi Xiaowei Ma Shuangchen Chen 《American Journal of Plant Sciences》 2013年第4期945-954,共10页
In this thesis, 10 species of kiwifruit rootstocks were treated with hydroponics hypoxia to study their root zone hypoxia tolerance. The results were as follows: growth of all kiwifruit seedlings was inhibited. The ma... In this thesis, 10 species of kiwifruit rootstocks were treated with hydroponics hypoxia to study their root zone hypoxia tolerance. The results were as follows: growth of all kiwifruit seedlings was inhibited. The max length of new root, plant height, plant biomass, root activity, relative growth rate of leaves, and content of chlorophyll in leaves under root zone hypoxia stress obviously declined comparing with control. MDA content, relative conductance in the leaves and roots all increased in 10 kinds of kiwifruit seedlings. The sensitivities of 10 kinds’ kiwifruit seedlings to hypoxia stress were obviously different. With the method of subordinate function and cluster analysis, the adversity resistance coefficient of 10 kinds’ kiwifruit seedlings, were comprehensively evaluated in order to appraise their hypoxia-tolerance abilities. According to the results, “Hayward”, “Qinmei”, “Jinxiang”, “Kuoye”, “Huayou” kiwifruit seedlings held higher tolerance to root zone hypoxia stress, while “Hongyang” kiwifruit seedlings were sensitive to root zone hypoxia stress. The others, including “Xixuan”, “Maohua”, “Jinhua”, “Shanli” kiwifruit seedlings kept moderate resistant intensity to root zone hypoxia stress. The kiwifruit seedlings’ resistance order from strong to weak was: “Hayward” > “Qinmei” > “Jinxiang” > “Kuoye” > “Huayou” > “Xixuan” > “Maohua” > “Jinhua” > “Shanli” > “Hongyang”. 展开更多
关键词 KIWIFRUIT ROOTSTOCK Root zone HYPOXIA Stress RESISTANT EVALUATION
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Research advances on drought resistance mechanism of plant species in arid zones of China 被引量:5
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作者 YaJuan Zhu Lei Li ZhiQing Jia 《Research in Cold and Arid Regions》 2011年第5期448-454,共7页
Drought and shortage of water resources, which restrict the economy, society development and environmental protection, are key factors in arid zones of China. In the arid zones of Western China, researching plant drou... Drought and shortage of water resources, which restrict the economy, society development and environmental protection, are key factors in arid zones of China. In the arid zones of Western China, researching plant drought resistance mechanism, selecting plant species with higher drought resistance, and developing water-saving techniques, are important for environmental improvement and economic development. This paper reviews research advances on drought resistance mechanism of plant species, based on research of morphological, physiological, and ecological adaptation mechanism of plant species under drought stress, such as anatomical structure of root systems and leaves, photosynthesis, antioxidant enzyme system, malondialdehyde (MDA), osmotic adjustment, endogenous hormone, drought-induced proteins and δ^13C. Finally, this paper points out the key field of future research. 展开更多
关键词 arid zone drought resistance drought resistance mechanism evaluated index
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