We conducted a study on the numerical calculation and response analysis of a transient electromagnetic field generated by a ground source in geological media. One solution method, the traditional discrete image method...We conducted a study on the numerical calculation and response analysis of a transient electromagnetic field generated by a ground source in geological media. One solution method, the traditional discrete image method, involves complex operation, and its digital filtering algorithm requires a large number of calculations. To solve these problems, we proposed an improved discrete image method, where the following are realized： the real number of the electromagnetic field solution based on the Gaver-Stehfest algorithm for approximate inversion, the exponential approximation of the objective kernel function using the Prony method, the transient electromagnetic field according to discrete image theory, and closed-form solution of the approximate coefficients. To verify the method, we tentatively calculated the transient electromagnetic field in a homogeneous model and compared it with the results obtained from the Hankel transform digital filtering method. The results show that the method has considerable accuracy and good applicability. We then used this method to calculate the transient electromagnetic field generated by a ground magnetic dipole source in a typical geoelectric model and analyzed the horizontal component response of the induced magnetic field obtained from the ＂ground excitation-stratum measurement method. We reached the conclusion that the horizontal component response of a transient field is related to the geoelectric structure, observation time, spatial location, and others. The horizontal component response of the induced magnetic field reflects the eddy current field distribution and its vertical gradient variation. During the detection of abnormal objects, positions with a zero or comparatively large offset were selected for the drill- hole measurements or a comparatively long observation delay was adopted to reduce the influence of the ambient field on the survey results. The discrete image method and forward calculation results in this paper can be used as references for relevant research.展开更多
统计能量分析(statistical energy analysis,SEA)是一种处理复杂耦合系统高频动力学响应的常用计算方法。该综述从经典统计能量分析(classical statistical energy analysis,CSEA)入手,详细介绍CSEA演化为SEA的进展历程,并从理论发展和...统计能量分析(statistical energy analysis,SEA)是一种处理复杂耦合系统高频动力学响应的常用计算方法。该综述从经典统计能量分析(classical statistical energy analysis,CSEA)入手,详细介绍CSEA演化为SEA的进展历程,并从理论发展和实际工程应用过程两方面对前人所做的大量工作进行概述,对SEA提出至今的理论推导及应用最新进展进行了系统归纳分析和总结。详细介绍总结了统计能量分析在工程实际中的一些典型成功应用案例及未来研究趋势。展开更多
Objective To study the genera and seasonal distribution of airborne pollen in Hubei province of China, and its relationship with pollinosis. Methods From November 2003 to October 2004, an airborne pollen investigation...Objective To study the genera and seasonal distribution of airborne pollen in Hubei province of China, and its relationship with pollinosis. Methods From November 2003 to October 2004, an airborne pollen investigation was performed in 16 chosen areas in 12 cities of Hubei province using gravity sedimentation technique. Meanwhile, univalent skin prick tests of pollens were performed and the invasion season was studied on 2 300 patients with pollinosis. Among them, 352 cases underwent the airway responsiveness measurements, and the correlation between airway responsiveness and results of pollen count was analyzed. Results A total of 61 pollen genera were observed and 257 520 pollens were collected. The peak of airborne pollen distribution occurred in two seasons each year: spring (March and April) and autumn (from August to October). The attack of pollinosis corresponded to the peak of pollen distribution. There was a significantly negative relationship between the provocation dose causing a 20% decrease of forced expiratory volume in one second (FEV1) from baseline and airborne pollen concentration (r = -0.6829, P < 0.05). Conclusion This study provides useful information for airborne pollen epidemiology of Hubei province, and it provides important insights to clinical prevention, diagnosis, and treatment of pollen-related allergic diseases.展开更多
The application of the response surface methodology and the central composite design（CCD） technique for modeling and optimization of the influence of some operating variables on copper,molybdenum and rhenium recover...The application of the response surface methodology and the central composite design（CCD） technique for modeling and optimization of the influence of some operating variables on copper,molybdenum and rhenium recoveries in a bioleaching process was investigated.Three main bioleaching parameters,namely pH,solid concentration and inoculum percent,were changed during the bioleaching tests based on CCD.The ranges of the bioleaching process variables used in the design were as follows：pH1.46-2.14,solid concentration 0.95%-11.05%,and inoculum percent 1.59%-18.41%.A total of 20 bioleaching tests were carried out by the CCD method according to software-based designed matrix.Empirical model equations were developed according to the copper,molybdenum and rhenium recoveries obtained with these three parameters.Model equations of responses at the base of parameters were achieved by using statistical software.The model equations were then individually optimized by using quadratic programming to maximize copper,molybdenum and rhenium recoveries individually within the experimental range.The optimum conditions for copper recovery were pH 1.68,solid concentration 0.95% and the inoculum 18.41%（v/v）,while molybdenum and rhenium recoveries were 2.18% and 24.41%,respectively.The predicted values for copper,molybdenum and rhenium recoveries were found to be in good agreement with the experimental values.Also jarosite formation during bioleaching tests was also investigated.展开更多
Deformation prediction and the analysis of underground goaf are important to the safe and efficient recovery of residual ore when shifting from open-pit mining to underground mining.To address the comprehensive proble...Deformation prediction and the analysis of underground goaf are important to the safe and efficient recovery of residual ore when shifting from open-pit mining to underground mining.To address the comprehensive problem of stability in the double mined-out area of the Tong-Lv-Shan(TLS)mine,which employed the dry stacked gangue technology,this paper applies the function fitting theory and a regression analysis method to screen the sensitive interval of four influencing factors based on single-factor experiments and the numerical simulation software FLAC3D.The influencing factors of the TLS mine consist of the column thickness(d),gob area span(D),boundary pillar thickness(h)and height of tailing gangue(H).The fitting degree between the four factors and the displacement of the gob roof(W)is reasonable because the correlation coefficient(R2)is greater than0.9701.After establishing29groups that satisfy the principles of Box-Behnken design(BBD),the dry gangue tailings process was re-simulated for the selected sensitive interval.Using a combination of an analysis of variance(ANOVA),regression equations and a significance analysis,the prediction results of the response surface methodology(RSM)show that the significant degree for the stability of the mined-out area for the factors satisfies the relationship of h>D>d>H.The importance of the four factors cannot be disregarded in a comparison of the prediction results of the engineering test stope in the TLS mine.By comparing the data of monitoring points and function prediction,the proposed method has shown promising results,and the prediction accuracy of RSM model is acceptable.The relative errors of the two test stopes are1.67%and3.85%,respectively,which yield satisfactory reliability and reference values for the mines.展开更多
The analytic response theory at density functional theory level is applied to investigate onephoton and two-photon absorption properties of a series of recently synthesized pyrene-core derivatives. The theoretical res...The analytic response theory at density functional theory level is applied to investigate onephoton and two-photon absorption properties of a series of recently synthesized pyrene-core derivatives. The theoretical results show that there are a few charge-transfer states for each compound in the lower energy region. The one-photon absorption properties of the five investigated compounds are highly consistent with those given by experimental measurements. The two-photon absorption intensities of the compounds are greatly enhanced with the increments of the molecular sizes, in which the two-photon absorption cross section of the four-branched compound is about 5.6 times of that of the mono-branched molecule. Fhrthermore, it is shown that the two-photon absorption properties are sensitive to the geometrical arrangements.展开更多
An experimental study was undertaken to express the hardening Swift law according to friction stir welding （FSW） aluminum alloy 2017. Tensile tests of welded joints were run in accordance with face centered composit...An experimental study was undertaken to express the hardening Swift law according to friction stir welding （FSW） aluminum alloy 2017. Tensile tests of welded joints were run in accordance with face centered composite design. Two types of identified models based on least square method and response surface method were used to assess the contribution of FSW independent factors on the hardening parameters. These models were introduced into finite-element code ＂Abaqus＂ to simulate tensile tests of welded joints. The relative average deviation criterion, between the experimental data and the numerical simulations of tension-elongation of tensile tests, shows good agreement between the experimental results and the predicted hardening models. These results can be used to perform multi-criteria optimization for carrying out specific welds or conducting numerical simulation of plastic deformation of forming process of FSW parts such as hydroforming, bending and forging.展开更多
Previous investigations have shown that the seismic response of slopes during the Wenchuan earthquake was highly variable. The present study tries to give an answer to the question： Which are the main factors affecti...Previous investigations have shown that the seismic response of slopes during the Wenchuan earthquake was highly variable. The present study tries to give an answer to the question： Which are the main factors affecting the seismic response degree of slopes？ With the support of the China Geological Survey Bureau, we set 3 monitoring sections in Jiulong slope, Mianzhu city, China with the aim to record the site response of the slope during the affershoeks of the Wenehuan earthquake. After the Wenchuan earthquake, which happened on 12 May 2008, 30 aftershocks have been recorded in these monitoring points. We analyzed 11 records, with magnitudes ranging from ML = 4.6 to ML = 3.1. The amplification factors of the horizontal compound PGA and 3D compound PGA have been determined for the 3 points at different elevations on the slope. Results showed that the dynamic response of the slope on the earthquake was controlled by factors such as topography and the thickness of the Quaternary overburden.展开更多
Effects of heat softening on the initiation of slide surface(shear banding) in clayey slopes during fast deformation were discussed.Controlling equations considering heat,pore pressure and mechanical movement were pre...Effects of heat softening on the initiation of slide surface(shear banding) in clayey slopes during fast deformation were discussed.Controlling equations considering heat,pore pressure and mechanical movement were presented.By perturbation method,the instability condition of localized zone(i.e.criterion for initiation of shear banding) for thermal related soils,such as clayey slope,was obtained.It is shown that slide surface initiates once the thermal-softening effects overcome the strain-hardening effects whether it is adiabatic or not.Without strain hardening effects,strain rate hardening obviously plays a role in initiation of shear band.During initiating process,heat is trapped inside the shear band,which leads rapidly to a pore pressure increase and fast loss of strength.The localized shear strain is concentrated in a narrow zone with a width of several centimeters at most and increases fast.This zone forms the sliding surface.Temperature can increase more than 2?C,pore pressure can increase 160% in about 0.1s inside this zone.These changes cause the fast decrease in friction-coefficient by about 36% over the initial value.That is how shear band initiated and developed in clayey slopes.展开更多
Parameter estimation of the attributed scattering center(ASC) model is significant for automatic target recognition(ATR). Sparse representation based parameter estimation methods have developed rapidly. Construction o...Parameter estimation of the attributed scattering center(ASC) model is significant for automatic target recognition(ATR). Sparse representation based parameter estimation methods have developed rapidly. Construction of the separable dictionary is a key issue for sparse representation technology. A compressive time-domain dictionary(TD) for ASC model is presented. Two-dimensional frequency domain responses of the ASC are produced and transformed into the time domain. Then these time domain responses are cutoff and stacked into vectors. These vectored time-domain responses are amalgamated to form the TD. Compared with the traditional frequency-domain dictionary(FD), the TD is a matrix that is quite spare and can markedly reduce the data size of the dictionary. Based on the basic TD construction method, we present four extended TD construction methods, which are available for different applications. In the experiments, the performance of the TD, including the basic model and the extended models, has been firstly analyzed in comparison with the FD. Secondly, an example of parameter estimation from SAR synthetic aperture radar(SAR) measurements of a target collected in an anechoic room is exhibited. Finally, a sparse image reconstruction example is from two apart apertures. Experimental results demonstrate the effectiveness and efficiency of the proposed TD.展开更多
[ Objective ] To optimize the ultrasonic extraction technology of cottonseed oil by response surface methodology. [ Method ] Based on the single factor experiment, the response surface method with three factors at thr...[ Objective ] To optimize the ultrasonic extraction technology of cottonseed oil by response surface methodology. [ Method ] Based on the single factor experiment, the response surface method with three factors at three levels was adopted according to the principle of central composite design, The optimum extraction conditions of extraction duration, liquid-solid ratio and temperature were determined by regression analysis. [ Re- salt] The best ultrasonic extraction conditions of cottonseed oil were 35 min of extraction duration, 38 ℃ of extraction temperature and 56：6 of liquid-solid ratio. Under these conditions, the extraction rate of cottonseed oil could reach up to 45.81%, with a relative error of 0.13% from the theoreti-cal value of 45.94%. [ Conclusion] The method optimized the extraction technology and laid foundation for the further research of cottonseed oil. Key words Cottonseed oil; Ultrasonic extraction; Response surface method; China展开更多
In order to determine the area for oil and gas exploration in China’s north Sichuan basin,we have divided the time during which the Longmenshan foreland basin was formed into five periods,based on the sedimentary res...In order to determine the area for oil and gas exploration in China’s north Sichuan basin,we have divided the time during which the Longmenshan foreland basin was formed into five periods,based on the sedimentary response relationship of the foreland basin to structural evolution: 1) a late Triassic Noric period;2) an early-Middle Jurassic period;3) a late Jurassic to early Cretaceous period;4) a late Cretaceous to Paleogene-Neogene period and 5) the Quaternary period. As well,we analyzed the sedimentary environment and lithologic features of every basin-forming period. The results show that there are several favorable source-reservoir-cap assemblages in our study area,making it a major region for future oil and gas exploration in China’s northern Sichuan basin.展开更多
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China(No.41304082)the Young Scientists Fund of the Natural Science Foundation of Hebei Province(No.D2014403011)the Geological survey project of China Geological Survey(No.12120114090201)
文摘We conducted a study on the numerical calculation and response analysis of a transient electromagnetic field generated by a ground source in geological media. One solution method, the traditional discrete image method, involves complex operation, and its digital filtering algorithm requires a large number of calculations. To solve these problems, we proposed an improved discrete image method, where the following are realized： the real number of the electromagnetic field solution based on the Gaver-Stehfest algorithm for approximate inversion, the exponential approximation of the objective kernel function using the Prony method, the transient electromagnetic field according to discrete image theory, and closed-form solution of the approximate coefficients. To verify the method, we tentatively calculated the transient electromagnetic field in a homogeneous model and compared it with the results obtained from the Hankel transform digital filtering method. The results show that the method has considerable accuracy and good applicability. We then used this method to calculate the transient electromagnetic field generated by a ground magnetic dipole source in a typical geoelectric model and analyzed the horizontal component response of the induced magnetic field obtained from the ＂ground excitation-stratum measurement method. We reached the conclusion that the horizontal component response of a transient field is related to the geoelectric structure, observation time, spatial location, and others. The horizontal component response of the induced magnetic field reflects the eddy current field distribution and its vertical gradient variation. During the detection of abnormal objects, positions with a zero or comparatively large offset were selected for the drill- hole measurements or a comparatively long observation delay was adopted to reduce the influence of the ambient field on the survey results. The discrete image method and forward calculation results in this paper can be used as references for relevant research.
文摘统计能量分析(statistical energy analysis,SEA)是一种处理复杂耦合系统高频动力学响应的常用计算方法。该综述从经典统计能量分析(classical statistical energy analysis,CSEA)入手,详细介绍CSEA演化为SEA的进展历程,并从理论发展和实际工程应用过程两方面对前人所做的大量工作进行概述,对SEA提出至今的理论推导及应用最新进展进行了系统归纳分析和总结。详细介绍总结了统计能量分析在工程实际中的一些典型成功应用案例及未来研究趋势。
基金Supported by Science Research Foundation of Health Department of Hubei Province (LJ200220)
文摘Objective To study the genera and seasonal distribution of airborne pollen in Hubei province of China, and its relationship with pollinosis. Methods From November 2003 to October 2004, an airborne pollen investigation was performed in 16 chosen areas in 12 cities of Hubei province using gravity sedimentation technique. Meanwhile, univalent skin prick tests of pollens were performed and the invasion season was studied on 2 300 patients with pollinosis. Among them, 352 cases underwent the airway responsiveness measurements, and the correlation between airway responsiveness and results of pollen count was analyzed. Results A total of 61 pollen genera were observed and 257 520 pollens were collected. The peak of airborne pollen distribution occurred in two seasons each year: spring (March and April) and autumn (from August to October). The attack of pollinosis corresponded to the peak of pollen distribution. There was a significantly negative relationship between the provocation dose causing a 20% decrease of forced expiratory volume in one second (FEV1) from baseline and airborne pollen concentration (r = -0.6829, P < 0.05). Conclusion This study provides useful information for airborne pollen epidemiology of Hubei province, and it provides important insights to clinical prevention, diagnosis, and treatment of pollen-related allergic diseases.
基金supported by the National Iranian Copper Industry Co. and Geological Survey of Iran
文摘The application of the response surface methodology and the central composite design（CCD） technique for modeling and optimization of the influence of some operating variables on copper,molybdenum and rhenium recoveries in a bioleaching process was investigated.Three main bioleaching parameters,namely pH,solid concentration and inoculum percent,were changed during the bioleaching tests based on CCD.The ranges of the bioleaching process variables used in the design were as follows：pH1.46-2.14,solid concentration 0.95%-11.05%,and inoculum percent 1.59%-18.41%.A total of 20 bioleaching tests were carried out by the CCD method according to software-based designed matrix.Empirical model equations were developed according to the copper,molybdenum and rhenium recoveries obtained with these three parameters.Model equations of responses at the base of parameters were achieved by using statistical software.The model equations were then individually optimized by using quadratic programming to maximize copper,molybdenum and rhenium recoveries individually within the experimental range.The optimum conditions for copper recovery were pH 1.68,solid concentration 0.95% and the inoculum 18.41%（v/v）,while molybdenum and rhenium recoveries were 2.18% and 24.41%,respectively.The predicted values for copper,molybdenum and rhenium recoveries were found to be in good agreement with the experimental values.Also jarosite formation during bioleaching tests was also investigated.
基金Project(2017YFC0602902) supported by the National Science and Technology Pillar Program during the 13th Five-Year Plan Period,ChinaProject(2015CX005) supported by the Innovation Driven Plan of Central South University,ChinaProject(2016zzts445) supported by the Fundamental Research Funds for the Central Universities,China
文摘Deformation prediction and the analysis of underground goaf are important to the safe and efficient recovery of residual ore when shifting from open-pit mining to underground mining.To address the comprehensive problem of stability in the double mined-out area of the Tong-Lv-Shan(TLS)mine,which employed the dry stacked gangue technology,this paper applies the function fitting theory and a regression analysis method to screen the sensitive interval of four influencing factors based on single-factor experiments and the numerical simulation software FLAC3D.The influencing factors of the TLS mine consist of the column thickness(d),gob area span(D),boundary pillar thickness(h)and height of tailing gangue(H).The fitting degree between the four factors and the displacement of the gob roof(W)is reasonable because the correlation coefficient(R2)is greater than0.9701.After establishing29groups that satisfy the principles of Box-Behnken design(BBD),the dry gangue tailings process was re-simulated for the selected sensitive interval.Using a combination of an analysis of variance(ANOVA),regression equations and a significance analysis,the prediction results of the response surface methodology(RSM)show that the significant degree for the stability of the mined-out area for the factors satisfies the relationship of h>D>d>H.The importance of the four factors cannot be disregarded in a comparison of the prediction results of the engineering test stope in the TLS mine.By comparing the data of monitoring points and function prediction,the proposed method has shown promising results,and the prediction accuracy of RSM model is acceptable.The relative errors of the two test stopes are1.67%and3.85%,respectively,which yield satisfactory reliability and reference values for the mines.
文摘The analytic response theory at density functional theory level is applied to investigate onephoton and two-photon absorption properties of a series of recently synthesized pyrene-core derivatives. The theoretical results show that there are a few charge-transfer states for each compound in the lower energy region. The one-photon absorption properties of the five investigated compounds are highly consistent with those given by experimental measurements. The two-photon absorption intensities of the compounds are greatly enhanced with the increments of the molecular sizes, in which the two-photon absorption cross section of the four-branched compound is about 5.6 times of that of the mono-branched molecule. Fhrthermore, it is shown that the two-photon absorption properties are sensitive to the geometrical arrangements.
文摘An experimental study was undertaken to express the hardening Swift law according to friction stir welding （FSW） aluminum alloy 2017. Tensile tests of welded joints were run in accordance with face centered composite design. Two types of identified models based on least square method and response surface method were used to assess the contribution of FSW independent factors on the hardening parameters. These models were introduced into finite-element code ＂Abaqus＂ to simulate tensile tests of welded joints. The relative average deviation criterion, between the experimental data and the numerical simulations of tension-elongation of tensile tests, shows good agreement between the experimental results and the predicted hardening models. These results can be used to perform multi-criteria optimization for carrying out specific welds or conducting numerical simulation of plastic deformation of forming process of FSW parts such as hydroforming, bending and forging.
基金supported by National Natural Science Foundation of China (Grant No.41072231)China Geological Survey Bureau (Grant Nos 1212010914010 and 1212011220154)Program for Changjiang Scholars and Innovative Research Team in University" (Grant No. IRT0812)
文摘Previous investigations have shown that the seismic response of slopes during the Wenchuan earthquake was highly variable. The present study tries to give an answer to the question： Which are the main factors affecting the seismic response degree of slopes？ With the support of the China Geological Survey Bureau, we set 3 monitoring sections in Jiulong slope, Mianzhu city, China with the aim to record the site response of the slope during the affershoeks of the Wenehuan earthquake. After the Wenchuan earthquake, which happened on 12 May 2008, 30 aftershocks have been recorded in these monitoring points. We analyzed 11 records, with magnitudes ranging from ML = 4.6 to ML = 3.1. The amplification factors of the horizontal compound PGA and 3D compound PGA have been determined for the 3 points at different elevations on the slope. Results showed that the dynamic response of the slope on the earthquake was controlled by factors such as topography and the thickness of the Quaternary overburden.
基金funded by the National Natural Science Foundation of China (Grant No. 11272314 No. 51239010)+1 种基金the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20133514110004)the Research Project of Chinese Ministry of Transport (Grant No. 201331849A130)
文摘Effects of heat softening on the initiation of slide surface(shear banding) in clayey slopes during fast deformation were discussed.Controlling equations considering heat,pore pressure and mechanical movement were presented.By perturbation method,the instability condition of localized zone(i.e.criterion for initiation of shear banding) for thermal related soils,such as clayey slope,was obtained.It is shown that slide surface initiates once the thermal-softening effects overcome the strain-hardening effects whether it is adiabatic or not.Without strain hardening effects,strain rate hardening obviously plays a role in initiation of shear band.During initiating process,heat is trapped inside the shear band,which leads rapidly to a pore pressure increase and fast loss of strength.The localized shear strain is concentrated in a narrow zone with a width of several centimeters at most and increases fast.This zone forms the sliding surface.Temperature can increase more than 2?C,pore pressure can increase 160% in about 0.1s inside this zone.These changes cause the fast decrease in friction-coefficient by about 36% over the initial value.That is how shear band initiated and developed in clayey slopes.
基金Project(NCET-11-0866)supported by Education Ministry's new Century Excellent Talents Supporting Plan,China
文摘Parameter estimation of the attributed scattering center(ASC) model is significant for automatic target recognition(ATR). Sparse representation based parameter estimation methods have developed rapidly. Construction of the separable dictionary is a key issue for sparse representation technology. A compressive time-domain dictionary(TD) for ASC model is presented. Two-dimensional frequency domain responses of the ASC are produced and transformed into the time domain. Then these time domain responses are cutoff and stacked into vectors. These vectored time-domain responses are amalgamated to form the TD. Compared with the traditional frequency-domain dictionary(FD), the TD is a matrix that is quite spare and can markedly reduce the data size of the dictionary. Based on the basic TD construction method, we present four extended TD construction methods, which are available for different applications. In the experiments, the performance of the TD, including the basic model and the extended models, has been firstly analyzed in comparison with the FD. Secondly, an example of parameter estimation from SAR synthetic aperture radar(SAR) measurements of a target collected in an anechoic room is exhibited. Finally, a sparse image reconstruction example is from two apart apertures. Experimental results demonstrate the effectiveness and efficiency of the proposed TD.
文摘[ Objective ] To optimize the ultrasonic extraction technology of cottonseed oil by response surface methodology. [ Method ] Based on the single factor experiment, the response surface method with three factors at three levels was adopted according to the principle of central composite design, The optimum extraction conditions of extraction duration, liquid-solid ratio and temperature were determined by regression analysis. [ Re- salt] The best ultrasonic extraction conditions of cottonseed oil were 35 min of extraction duration, 38 ℃ of extraction temperature and 56：6 of liquid-solid ratio. Under these conditions, the extraction rate of cottonseed oil could reach up to 45.81%, with a relative error of 0.13% from the theoreti-cal value of 45.94%. [ Conclusion] The method optimized the extraction technology and laid foundation for the further research of cottonseed oil. Key words Cottonseed oil; Ultrasonic extraction; Response surface method; China
基金Projects 40772198 and 50678182 supported by the National Natural Science Foundation of China09-3-094 by the Research Fund for Teaching Reform in Institutes of Higher Learning,Chongqing, China
文摘In order to determine the area for oil and gas exploration in China’s north Sichuan basin,we have divided the time during which the Longmenshan foreland basin was formed into five periods,based on the sedimentary response relationship of the foreland basin to structural evolution: 1) a late Triassic Noric period;2) an early-Middle Jurassic period;3) a late Jurassic to early Cretaceous period;4) a late Cretaceous to Paleogene-Neogene period and 5) the Quaternary period. As well,we analyzed the sedimentary environment and lithologic features of every basin-forming period. The results show that there are several favorable source-reservoir-cap assemblages in our study area,making it a major region for future oil and gas exploration in China’s northern Sichuan basin.
