Hydrogen gas accelerates hydrocarbon generation, but little is known about its distribution and origin in petroliferous basins, which has hindered the further exploration.Taken the Jiyang Depression in eastern China a...Hydrogen gas accelerates hydrocarbon generation, but little is known about its distribution and origin in petroliferous basins, which has hindered the further exploration.Taken the Jiyang Depression in eastern China as an example, this study collected natural gas from different tectonic units, and analyzed various geochemical characters including gas contents, and carbon and hydrogen isotopic composition.The result shows that：（1） hydrogen gas is widespread distributed, but its content is very low, which typically ranges from 0.01% to 0.1% in this region;（2） the ratios of H2/3He, indicative of the origins of hydrogen gas, suggest that mantle-derived hydrogen is dominant.Even in tectonically stable areas absent with deep fluid activities, there is also mantle-derived;（3） the isotopic composition of hydrogen falls in the range of –798‰ to –628‰（relative to VSMOW standard）.In areas with deep-derived fluids, the hydrogen gas has a similar isotopic composition with the previously documented deep-sourced gas, with lighter isotopic composition.In contrast, hydrogen gas has a heavier isotopic composition in relatively stable areas.The isotopic signatures suggest that there is a mixture of mantle- and crust-derived hydrogen gas in the relatively stable area, which is consistent with the H2/3He ratios.Therefore, it is clear that the hydrogen gas has a much wider distribution than found in the deep-derived fluid area, resulting in a much broader area with hydrogenating effect for resource rock.This understanding will provide new insights for hydrocarbon generation research and resource assessment in petroliferous basins.展开更多
Particle Impact Drilling(PID)is a novel method to improve the rate of penetration(ROP).In order to further improve the performance of PID,an investigation into the effect of single and double particles:(1)diameter;(2)...Particle Impact Drilling(PID)is a novel method to improve the rate of penetration(ROP).In order to further improve the performance of PID,an investigation into the effect of single and double particles:(1)diameter;(2)initial velocity;(3)distance;and(4)angle of incidence was undertaken to investigate their effects on broken volume and penetration depth into hard brittle rock.For this purpose,the laboratory experiment of single particle impact rock was employed.Meanwhile,based on the LS-DYNA,a new finite element(FE)simulation of the PID,including single and double particles impact rock,has been presented.The 3-dimensional(3D),aix-symmetric,dynamicexplicit,Lagrangian model has been considered in this simulation.And the Elastic and Holmquist Johnson Cook(HJC)material behaviors have been used for particles and rocks,respectively.The FE simulation results of single particle impacting rock are good agreement with experimental data.Furthermore,in this article the optimal impact parameters,including diameter,initial velocity,distance and the angle of incidence,are obtained in PID.展开更多
It has been confirmed that the key source rocks of Qiongdongnan Basin are associated with the Yacheng Formation, which was deposited in a transitional marine-continental environment. Because the distribution and evolu...It has been confirmed that the key source rocks of Qiongdongnan Basin are associated with the Yacheng Formation, which was deposited in a transitional marine-continental environment. Because the distribution and evolution patterns of the source rocks in the major depressions are different, it is important to determine the most abundant hydrocarbon-generation depressions in terms of exploration effectiveness. Based on an analysis of organic matter characteristics of the source rocks, in combination with drilling data and seismic data, this paper establishes a model to evaluate the hydrocarbon-generation depressions in the deepwater area of Qiongdongnan Basin. First of all, by using the method of seismic-facies model analysis, the distribution of sedimentary facies was determined. Then, the sedimentary facies were correlated with the organic facies, and the distribution of organic facies was predicted. Meanwhile, the thickness of source rocks for all the depressions was calculated on the basis of a quantitative analysis of seismic velocity and lithology. The relationship between mudstone porosity and vitrinite reflectance（Ro） was used to predict the maturity of source rocks. Second, using the parameters such as thickness and maturity of source rocks, the quantity and intensity of gas generation for Yacheng and Lingshui Formations were calculated. Finally, in combination with the identified hydrocarbon resources, the quantity and intensity of gas generation were used as a guide to establish an evaluation standard for hydrocarbon-generation depressions, which was optimized for the main depressions in the Central Depression Belt. It is proposed that Lingshui, Ledong, Baodao and Changchang Depressions are the most abundant hydrocarbon depressions, whilst Songnan and Beijiao Depressions are rich hydrocarbon depressions. Such an evaluation procedure is beneficial to the next stage of exploration in the deep-water area of Qiongdongnan Basin.展开更多
In order to reveal the nature of the segmentation of Longmen Mountains Thrust Belt caused by the three nappes (Jiaoziding, Jiudingshan, and Baoxing Nappe), several methods are applied in this paper, including field in...In order to reveal the nature of the segmentation of Longmen Mountains Thrust Belt caused by the three nappes (Jiaoziding, Jiudingshan, and Baoxing Nappe), several methods are applied in this paper, including field investigation, seismic explanation and balanced crossed section, etc. Results of research reveal that nappes in Longmen Mountains vary in geometry, kinematics, and dynamics. Jiaoziding Nappe has generally behaved in a ductile manner, whereas Jiudingshan Nappe has been rigid, and the rheology of Baoxing Nappe has been intermediate between that of the other two nappes. The development of nappes has resulted in tectonic segmentation of Longmen Mountains: the main structural style of the northern segment is thrust faulting, with Jiaoziding Nappe representing a giant syncline. Given its ductility, it absorbed lots of stress, with the least amount of tectonic shortening in the SE part of the nappe. In the middle segment, the deformation is controlled by the rigid Jiudingshan Nappe, whose frontal area records lots of tectonic shortening. Deformation in the southern segment is intermediate in character between that of the other two segments, characterized by horizontal zonation, as demonstrated by fault development, and vertical stratification, which indicates that fault development was controlled by lithology.展开更多
基金funded by the National Natural Science Foundation of China (Grant Nos.:41102075 and 41230312)the Open Fund of Key Laboratory of Tectonics and Petroleum Resources (China University of Geosciences), Ministry of Education (Grant No.: TPR-2012-24)
文摘Hydrogen gas accelerates hydrocarbon generation, but little is known about its distribution and origin in petroliferous basins, which has hindered the further exploration.Taken the Jiyang Depression in eastern China as an example, this study collected natural gas from different tectonic units, and analyzed various geochemical characters including gas contents, and carbon and hydrogen isotopic composition.The result shows that：（1） hydrogen gas is widespread distributed, but its content is very low, which typically ranges from 0.01% to 0.1% in this region;（2） the ratios of H2/3He, indicative of the origins of hydrogen gas, suggest that mantle-derived hydrogen is dominant.Even in tectonically stable areas absent with deep fluid activities, there is also mantle-derived;（3） the isotopic composition of hydrogen falls in the range of –798‰ to –628‰（relative to VSMOW standard）.In areas with deep-derived fluids, the hydrogen gas has a similar isotopic composition with the previously documented deep-sourced gas, with lighter isotopic composition.In contrast, hydrogen gas has a heavier isotopic composition in relatively stable areas.The isotopic signatures suggest that there is a mixture of mantle- and crust-derived hydrogen gas in the relatively stable area, which is consistent with the H2/3He ratios.Therefore, it is clear that the hydrogen gas has a much wider distribution than found in the deep-derived fluid area, resulting in a much broader area with hydrogenating effect for resource rock.This understanding will provide new insights for hydrocarbon generation research and resource assessment in petroliferous basins.
基金The authors are grateful for the financial support from the Natural Science Foundation of China(NSFC)(No.50874095,No.51174173 and No.51374176)the China National Science and Technology Major Project(No.2011ZX05050)Graduate Innovation Foundation of College of Mechatronic Engineering,Southwest Petroleum University(No.CX2014SZ03).Without their support,this work would not have been possible.
文摘Particle Impact Drilling(PID)is a novel method to improve the rate of penetration(ROP).In order to further improve the performance of PID,an investigation into the effect of single and double particles:(1)diameter;(2)initial velocity;(3)distance;and(4)angle of incidence was undertaken to investigate their effects on broken volume and penetration depth into hard brittle rock.For this purpose,the laboratory experiment of single particle impact rock was employed.Meanwhile,based on the LS-DYNA,a new finite element(FE)simulation of the PID,including single and double particles impact rock,has been presented.The 3-dimensional(3D),aix-symmetric,dynamicexplicit,Lagrangian model has been considered in this simulation.And the Elastic and Holmquist Johnson Cook(HJC)material behaviors have been used for particles and rocks,respectively.The FE simulation results of single particle impacting rock are good agreement with experimental data.Furthermore,in this article the optimal impact parameters,including diameter,initial velocity,distance and the angle of incidence,are obtained in PID.
基金The National Science and Technology Major Project of the Ministry of Science and Technology of China under contract No.2011ZX05025
文摘It has been confirmed that the key source rocks of Qiongdongnan Basin are associated with the Yacheng Formation, which was deposited in a transitional marine-continental environment. Because the distribution and evolution patterns of the source rocks in the major depressions are different, it is important to determine the most abundant hydrocarbon-generation depressions in terms of exploration effectiveness. Based on an analysis of organic matter characteristics of the source rocks, in combination with drilling data and seismic data, this paper establishes a model to evaluate the hydrocarbon-generation depressions in the deepwater area of Qiongdongnan Basin. First of all, by using the method of seismic-facies model analysis, the distribution of sedimentary facies was determined. Then, the sedimentary facies were correlated with the organic facies, and the distribution of organic facies was predicted. Meanwhile, the thickness of source rocks for all the depressions was calculated on the basis of a quantitative analysis of seismic velocity and lithology. The relationship between mudstone porosity and vitrinite reflectance（Ro） was used to predict the maturity of source rocks. Second, using the parameters such as thickness and maturity of source rocks, the quantity and intensity of gas generation for Yacheng and Lingshui Formations were calculated. Finally, in combination with the identified hydrocarbon resources, the quantity and intensity of gas generation were used as a guide to establish an evaluation standard for hydrocarbon-generation depressions, which was optimized for the main depressions in the Central Depression Belt. It is proposed that Lingshui, Ledong, Baodao and Changchang Depressions are the most abundant hydrocarbon depressions, whilst Songnan and Beijiao Depressions are rich hydrocarbon depressions. Such an evaluation procedure is beneficial to the next stage of exploration in the deep-water area of Qiongdongnan Basin.
文摘In order to reveal the nature of the segmentation of Longmen Mountains Thrust Belt caused by the three nappes (Jiaoziding, Jiudingshan, and Baoxing Nappe), several methods are applied in this paper, including field investigation, seismic explanation and balanced crossed section, etc. Results of research reveal that nappes in Longmen Mountains vary in geometry, kinematics, and dynamics. Jiaoziding Nappe has generally behaved in a ductile manner, whereas Jiudingshan Nappe has been rigid, and the rheology of Baoxing Nappe has been intermediate between that of the other two nappes. The development of nappes has resulted in tectonic segmentation of Longmen Mountains: the main structural style of the northern segment is thrust faulting, with Jiaoziding Nappe representing a giant syncline. Given its ductility, it absorbed lots of stress, with the least amount of tectonic shortening in the SE part of the nappe. In the middle segment, the deformation is controlled by the rigid Jiudingshan Nappe, whose frontal area records lots of tectonic shortening. Deformation in the southern segment is intermediate in character between that of the other two segments, characterized by horizontal zonation, as demonstrated by fault development, and vertical stratification, which indicates that fault development was controlled by lithology.
