The time-frequency electromagnetic （TFEM） method combines frequency-domain sounding with time-domain sounding to form a comprehensive system so that it is possible to select different frequencies and induce waves ac...The time-frequency electromagnetic （TFEM） method combines frequency-domain sounding with time-domain sounding to form a comprehensive system so that it is possible to select different frequencies and induce waves according to the objective depth to be explored. During processing not only resistivity but also polarization information can be provided so we can study resistivity as well as predict oil-bearing characteristics simultaneously. Timedomain resistivity information is obtained by pseudo-2D resistivity inversion and frequencydomain IP information is obtained using the Cole-Cole model. Some successful applications in western China show that it provides unique results in an overthrust zone, deep igneous rock investigation, and hydrocarbon prediction.展开更多
There are some differences in reservoir quality of clastic rock between the hanging wall and the foot wall of the Ke-Bai overthrust belt, northwestern margin of the Junggar Basin, western China, which affect the effic...There are some differences in reservoir quality of clastic rock between the hanging wall and the foot wall of the Ke-Bai overthrust belt, northwestern margin of the Junggar Basin, western China, which affect the efficient petroleum exploration in this highly mature exploration area. Based on a large number of thin-sections, cast thin-sections, and physical property analysis of cores, we systematically discuss the Permian-Jurassic reservoir differences between the hanging wall and the foot wall of the Ke- Bai overthrust fault from the aspects of structural evolution, time-space distribution of the depositional system, diagenesis characteristics, and reservoir quality and analyzed the reasons for the differences in reservoir properties. The overthrusting of the Ke-Bai fault directly results in different burial histories, diagenesis evolution, and porosity evolution between the hanging wall and the foot wall. The diflbrences of reservoir characteristics are mainly embodied in buried depth, grain size, sedimentary facies, diagenetic stage, and reservoir quality. The analysis results showed that burial history and depositional characteristics controlled by overthrusting are direct influencing factors of reservoir differences. Because of shallow burial depth of the hanging wall, the reservoir compaction is weak and primary pores are preserved well. The porosity of reservoir on the hanging wall is generally 10%-25%. The strata on the foot wall are deeply buried, and there are mainly mixed pores with the average porosity of 5%-20%. The favorable reservoir on the foot wall is generally developed near faults or in the channel sand bodies, which are usually dissolution development areas.展开更多
On the basis of interpretation of comprehensive geophysical data and foreign data analysis,there existed a lot of overburden detachment shear thrust faults along the southeastern margin of Nansha Trough,which composed...On the basis of interpretation of comprehensive geophysical data and foreign data analysis,there existed a lot of overburden detachment shear thrust faults along the southeastern margin of Nansha Trough,which composed imbricated overthrust nappe structure.Thrust-faulted nappe structure pattern is determined in this area,which consists of frontal fault zone,thrust fault-folded zone and root zone structures,and presents regularly zonation on plane.The detail description of the structural geometrical characteristics is given in shallow thrust fault zone,and the kinematical mechanism of thrust fault nappe structure is furtherly discussed.Overthrnst nappe structure in this area is resulted from island arc-continent collision and orogenic activities.展开更多
The arcuate nappe structure on the north edge of the Wuliang Mountains in westernYunnan Province is a complex nappe structural system with multiple superimposed structures.The autochthonous system is a WNW-trending ar...The arcuate nappe structure on the north edge of the Wuliang Mountains in westernYunnan Province is a complex nappe structural system with multiple superimposed structures.The autochthonous system is a WNW-trending arcuate fold belt consisting of the Jurassic andCretaceous and the allochthonous system is mainly composed of Upper Triassic rocks. Generally,the nappe structure moved from south to north, with the hanging wall thrusting in a WNW direc-tion for a distance of over 10km. The deep nappe structural system was formed at depths ofabout 5-10km in an environment not exceeding the greenschist facies. It occurred in theOligocene (about 40-20 Ma).展开更多
文摘The time-frequency electromagnetic （TFEM） method combines frequency-domain sounding with time-domain sounding to form a comprehensive system so that it is possible to select different frequencies and induce waves according to the objective depth to be explored. During processing not only resistivity but also polarization information can be provided so we can study resistivity as well as predict oil-bearing characteristics simultaneously. Timedomain resistivity information is obtained by pseudo-2D resistivity inversion and frequencydomain IP information is obtained using the Cole-Cole model. Some successful applications in western China show that it provides unique results in an overthrust zone, deep igneous rock investigation, and hydrocarbon prediction.
基金supported by the National Program for Fundamental Research and Development (973 Program 2006CB202306)
文摘There are some differences in reservoir quality of clastic rock between the hanging wall and the foot wall of the Ke-Bai overthrust belt, northwestern margin of the Junggar Basin, western China, which affect the efficient petroleum exploration in this highly mature exploration area. Based on a large number of thin-sections, cast thin-sections, and physical property analysis of cores, we systematically discuss the Permian-Jurassic reservoir differences between the hanging wall and the foot wall of the Ke- Bai overthrust fault from the aspects of structural evolution, time-space distribution of the depositional system, diagenesis characteristics, and reservoir quality and analyzed the reasons for the differences in reservoir properties. The overthrusting of the Ke-Bai fault directly results in different burial histories, diagenesis evolution, and porosity evolution between the hanging wall and the foot wall. The diflbrences of reservoir characteristics are mainly embodied in buried depth, grain size, sedimentary facies, diagenetic stage, and reservoir quality. The analysis results showed that burial history and depositional characteristics controlled by overthrusting are direct influencing factors of reservoir differences. Because of shallow burial depth of the hanging wall, the reservoir compaction is weak and primary pores are preserved well. The porosity of reservoir on the hanging wall is generally 10%-25%. The strata on the foot wall are deeply buried, and there are mainly mixed pores with the average porosity of 5%-20%. The favorable reservoir on the foot wall is generally developed near faults or in the channel sand bodies, which are usually dissolution development areas.
文摘On the basis of interpretation of comprehensive geophysical data and foreign data analysis,there existed a lot of overburden detachment shear thrust faults along the southeastern margin of Nansha Trough,which composed imbricated overthrust nappe structure.Thrust-faulted nappe structure pattern is determined in this area,which consists of frontal fault zone,thrust fault-folded zone and root zone structures,and presents regularly zonation on plane.The detail description of the structural geometrical characteristics is given in shallow thrust fault zone,and the kinematical mechanism of thrust fault nappe structure is furtherly discussed.Overthrnst nappe structure in this area is resulted from island arc-continent collision and orogenic activities.
文摘The arcuate nappe structure on the north edge of the Wuliang Mountains in westernYunnan Province is a complex nappe structural system with multiple superimposed structures.The autochthonous system is a WNW-trending arcuate fold belt consisting of the Jurassic andCretaceous and the allochthonous system is mainly composed of Upper Triassic rocks. Generally,the nappe structure moved from south to north, with the hanging wall thrusting in a WNW direc-tion for a distance of over 10km. The deep nappe structural system was formed at depths ofabout 5-10km in an environment not exceeding the greenschist facies. It occurred in theOligocene (about 40-20 Ma).
