Unconventional resources (oil, gas, and geothermal) are often buried deep underground within dense rock strata and complex geological structures, making it increasingly difficult to create volumetric fractures through...Unconventional resources (oil, gas, and geothermal) are often buried deep underground within dense rock strata and complex geological structures, making it increasingly difficult to create volumetric fractures through conventional hydraulic fracturing. This paper introduces a novel method of supercritical energetic fluid thermal shock fracturing. It pioneers a CO_(2) deflagration impact triaxial pneumatic fracturing experimental system, using high-strength similar materials to simulate deep, hard rock masses. The study investigates the rock-breaking process and crack propagation patterns under supercritical CO_(2) thermal shock, revealing and discussing the types of thermal shock-induced fractures, their formation conditions, and discrimination criteria. The research indicates that higher supercritical CO_(2) thermal shock pressures and faster pressure release rates facilitate the formation of radial branching fractures, circumferential cracks, and branch cracks. Typically, CO_(2) thermal shock generates 3–5 radial main cracks, which is significantly more than the single main crack formed by hydraulic fracturing. The formation of branched cracks is often caused by compression-shear failure and occurs under relatively harsh conditions, determined by the confining pressure, rock properties, peak thermal shock pressure, and the pressure sustained post-decompression. The findings are expected to offer a safe, efficient, and controllable shockwave method of supercritical fluid thermal shock fracturing for the exploitation of deep unconventional oil and gas resources.展开更多
Late Mesoproterozoic igneous rocks in the SW Yangtze Block are important for understanding the role of it in reconstruction of the Rodinia supercontinent.In the present study,we report new geochronological,geochemical...Late Mesoproterozoic igneous rocks in the SW Yangtze Block are important for understanding the role of it in reconstruction of the Rodinia supercontinent.In the present study,we report new geochronological,geochemical,and Nd-Hf isotopic data for the Cuoke plagioclase amphibolites and granites in the SW Yangtze Block.Geochronological results show that the plagioclase amphibolites and granites have similar late Mesoproterozoic zircon U-Pb ages of 1168-1162 Ma,constituting a bimodal igneous assemblage.The plagioclase amphibolites have high and variable TiO2 contents(1.15-4.30 wt.%)and Mg#(34-66)values,similar to the tholeiitic series.They are characterized by enrichment in LREEs and LILEs,and have OIB-like affinities with positive Nb and Ta anomalies.The plagioclase amphibolites have positive whole-rockεNd(t)(+3.2 to+4.3)and zirconεHf(t)(+4.3 to+10.7)values,indicating that they were derived from an OIB-like asthenospheric mantle source.The granites belong to the reduced peralkaline A-type series and have negativeεNd(t)value of-6.0 andεHf(t)values of-5.8 to-13.8,indicating a derivation from the partial melting of ancient mafic lower crust.In combination with the~1.05-1.02 Ga bimodal igneous assemblage in the SW Yangtze Block,we propose that the Cuoke 1168-1162 Ma igneous rocks were likely formed in a continental rift basin and argue against the existance of Grenvillian Orogen in the SW Yangtze Block during the late Mesoproterozoic.展开更多
Recent geological survey has identified the Early Paleoproterozoic meta-mafic intrusions in the southwestern Yangtze Block.We present geochronological,whole-rock geochemical and Nd isotopic data for these meta-mafic r...Recent geological survey has identified the Early Paleoproterozoic meta-mafic intrusions in the southwestern Yangtze Block.We present geochronological,whole-rock geochemical and Nd isotopic data for these meta-mafic rocks to better address the tectonic evolution of the Yangtze Block during the Early Paleoproterozoic Period.Geochronological data show that the meta-mafic rocks have zircon ages of 2 395-2 316 Ma.They have high TiO_2 contents of 1.40 wt.%-3.66 wt.% and Nb concentrations of 13.7 ppm-45.5 ppm,thus aregrouped as Nb-enriched mafic rocks.These mafic rocks are characterized by tholeiitic compositions with enrichment of LREEs and LILEs,and can be divided into two groups.Group 1 samples display E-MORB-like geochemical characteristics.Group 2 samples have positive ENd(t) values of 4.0-5.0.Geochemical data indicate that all meta-mafic rocks were likely derived from a depleted asthenospheric mantle.REE modeling indicates lower degree of partial melting for Group 2 samples(3%-10%) relative to Group 1 samples(15%-20%).Taking into account contemporaneous post-collisional granitoids in southwestern Yangtze Block,we propose that these meta-mafic rocks were formed in a post-collisional extension setting.These meta-mafic rocks can be compared with those in Africa,South America and Europe,and might be linked with the Arrowsmith orogenic belt.展开更多
When the traditional drill and blast method is applied to rock crushing projects,it has strong vibration,loud noise and dust pollution,so it cannot be used in densely populated areas such as urban public works.We deve...When the traditional drill and blast method is applied to rock crushing projects,it has strong vibration,loud noise and dust pollution,so it cannot be used in densely populated areas such as urban public works.We developed a supercritical CO_(2)true triaxial pneumatic rock-breaking experimental system,and conducted laboratory and field tests of dry ice powder pneumatic rock-breaking.The characteristics of the blast-induced vibration velocity waveform and the evolution of the vibration velocity and frequency with the focal distance were analyzed and discussed.The fracturing mechanism of dry ice powder pneumatic rock breaking is studied.The research results show that:(1)The vibration velocity induced by dry ice powder pneumatic rock breaking decays as a power function with the increase of the focal distance;(2)The vibration frequency caused by dry ice powder pneumatic rock breaking is mainly distributed in 1–120 Hz.Due to the dispersion effect,the dominant frequency of 10–30 Hz appears abnormally attenuated;(3)The traditional CO_(2)phase change fracturing energy calculation formula is also applicable to dry ice pneumatic rock breaking technology,and the trinitrotoluene(TNT)equivalent of fracturing energy is applicable to the Sadovsky formula;(4)Dry ice powder pneumatic rock breaking is shock wave and highenergy gas acting together to fracture rock,which can be divided into three stages,among which the gas wedge action of high-energy gas plays a dominant role in rock mass damage.展开更多
With the development of mobile technology, especially the development of 3G and mobile IP, the computational capacity of handsets is becoming more and more powerful, which provides a new method to solve the difficulti...With the development of mobile technology, especially the development of 3G and mobile IP, the computational capacity of handsets is becoming more and more powerful, which provides a new method to solve the difficulties encountered in real time GIS accessing caused by the characteristics of mobility and remoteness of fieldwork in oilfield. On the basis of studying in-depth on the technologies of J2ME platform, Mobile SVG and mobile data transfer, etc., and in accordance with the actual situation of oilfield, the design framework of oilfield mobile GIS service is put forward and the schemes of key technologies are given in this paper, which establishes the technical foundation for the construction of “Digital Oilfield”.展开更多
基金supported by“Intergovernmental Cooperation in Science,Technology and Innovation(ISTI)”Key Special Project 2023“Intergovernmental Cooperation Programme between China and the United States”(Grant No.2023YFE0120500)the National Natural Science Foundation of China(Grant No.41702289)the Foundation of Hubei Key Laboratory of Blasting Engineering(Grant No.HKLBEF202004).
文摘Unconventional resources (oil, gas, and geothermal) are often buried deep underground within dense rock strata and complex geological structures, making it increasingly difficult to create volumetric fractures through conventional hydraulic fracturing. This paper introduces a novel method of supercritical energetic fluid thermal shock fracturing. It pioneers a CO_(2) deflagration impact triaxial pneumatic fracturing experimental system, using high-strength similar materials to simulate deep, hard rock masses. The study investigates the rock-breaking process and crack propagation patterns under supercritical CO_(2) thermal shock, revealing and discussing the types of thermal shock-induced fractures, their formation conditions, and discrimination criteria. The research indicates that higher supercritical CO_(2) thermal shock pressures and faster pressure release rates facilitate the formation of radial branching fractures, circumferential cracks, and branch cracks. Typically, CO_(2) thermal shock generates 3–5 radial main cracks, which is significantly more than the single main crack formed by hydraulic fracturing. The formation of branched cracks is often caused by compression-shear failure and occurs under relatively harsh conditions, determined by the confining pressure, rock properties, peak thermal shock pressure, and the pressure sustained post-decompression. The findings are expected to offer a safe, efficient, and controllable shockwave method of supercritical fluid thermal shock fracturing for the exploitation of deep unconventional oil and gas resources.
基金supported by the Guangdong Basic and Applied Basic Research Foundation(Grant Nos.2019B1515120019,2018B030312007)National Natural Science Foundation of China(Grant Nos.U1701641,41830211,41702230)the District Summary and Service Product Develop of Yunnan Region Geologic Survey,China(Grant No.121201102000150012-02)。
文摘Late Mesoproterozoic igneous rocks in the SW Yangtze Block are important for understanding the role of it in reconstruction of the Rodinia supercontinent.In the present study,we report new geochronological,geochemical,and Nd-Hf isotopic data for the Cuoke plagioclase amphibolites and granites in the SW Yangtze Block.Geochronological results show that the plagioclase amphibolites and granites have similar late Mesoproterozoic zircon U-Pb ages of 1168-1162 Ma,constituting a bimodal igneous assemblage.The plagioclase amphibolites have high and variable TiO2 contents(1.15-4.30 wt.%)and Mg#(34-66)values,similar to the tholeiitic series.They are characterized by enrichment in LREEs and LILEs,and have OIB-like affinities with positive Nb and Ta anomalies.The plagioclase amphibolites have positive whole-rockεNd(t)(+3.2 to+4.3)and zirconεHf(t)(+4.3 to+10.7)values,indicating that they were derived from an OIB-like asthenospheric mantle source.The granites belong to the reduced peralkaline A-type series and have negativeεNd(t)value of-6.0 andεHf(t)values of-5.8 to-13.8,indicating a derivation from the partial melting of ancient mafic lower crust.In combination with the~1.05-1.02 Ga bimodal igneous assemblage in the SW Yangtze Block,we propose that the Cuoke 1168-1162 Ma igneous rocks were likely formed in a continental rift basin and argue against the existance of Grenvillian Orogen in the SW Yangtze Block during the late Mesoproterozoic.
基金jointly supported by the National Natural Science Foundation of China(Nos.U1701641,41702230)the District Summary and Service Product Develop of Yunnan Region Geologic Survey(No.121201102000150012-02)+1 种基金Yunnan Province Geological Survey Foundation(No.2013HA001)Natural Science Foundation of Guangdong Province(No.2018B030312007)
文摘Recent geological survey has identified the Early Paleoproterozoic meta-mafic intrusions in the southwestern Yangtze Block.We present geochronological,whole-rock geochemical and Nd isotopic data for these meta-mafic rocks to better address the tectonic evolution of the Yangtze Block during the Early Paleoproterozoic Period.Geochronological data show that the meta-mafic rocks have zircon ages of 2 395-2 316 Ma.They have high TiO_2 contents of 1.40 wt.%-3.66 wt.% and Nb concentrations of 13.7 ppm-45.5 ppm,thus aregrouped as Nb-enriched mafic rocks.These mafic rocks are characterized by tholeiitic compositions with enrichment of LREEs and LILEs,and can be divided into two groups.Group 1 samples display E-MORB-like geochemical characteristics.Group 2 samples have positive ENd(t) values of 4.0-5.0.Geochemical data indicate that all meta-mafic rocks were likely derived from a depleted asthenospheric mantle.REE modeling indicates lower degree of partial melting for Group 2 samples(3%-10%) relative to Group 1 samples(15%-20%).Taking into account contemporaneous post-collisional granitoids in southwestern Yangtze Block,we propose that these meta-mafic rocks were formed in a post-collisional extension setting.These meta-mafic rocks can be compared with those in Africa,South America and Europe,and might be linked with the Arrowsmith orogenic belt.
基金supported by the State Key Laboratory Open Fund(No.HKLBEF202004)the Natural Science Foundation of Jiangsu Province(No.BK20201313)+2 种基金the Key Program of National Natural Science Foundation of China(No.51934007)the Major Scientific and Technological Innovation Program in Shandong Province(No.2019JZZY020505)the National Key Research and Development Program of China(No.2022YFC3004700)。
文摘When the traditional drill and blast method is applied to rock crushing projects,it has strong vibration,loud noise and dust pollution,so it cannot be used in densely populated areas such as urban public works.We developed a supercritical CO_(2)true triaxial pneumatic rock-breaking experimental system,and conducted laboratory and field tests of dry ice powder pneumatic rock-breaking.The characteristics of the blast-induced vibration velocity waveform and the evolution of the vibration velocity and frequency with the focal distance were analyzed and discussed.The fracturing mechanism of dry ice powder pneumatic rock breaking is studied.The research results show that:(1)The vibration velocity induced by dry ice powder pneumatic rock breaking decays as a power function with the increase of the focal distance;(2)The vibration frequency caused by dry ice powder pneumatic rock breaking is mainly distributed in 1–120 Hz.Due to the dispersion effect,the dominant frequency of 10–30 Hz appears abnormally attenuated;(3)The traditional CO_(2)phase change fracturing energy calculation formula is also applicable to dry ice pneumatic rock breaking technology,and the trinitrotoluene(TNT)equivalent of fracturing energy is applicable to the Sadovsky formula;(4)Dry ice powder pneumatic rock breaking is shock wave and highenergy gas acting together to fracture rock,which can be divided into three stages,among which the gas wedge action of high-energy gas plays a dominant role in rock mass damage.
文摘With the development of mobile technology, especially the development of 3G and mobile IP, the computational capacity of handsets is becoming more and more powerful, which provides a new method to solve the difficulties encountered in real time GIS accessing caused by the characteristics of mobility and remoteness of fieldwork in oilfield. On the basis of studying in-depth on the technologies of J2ME platform, Mobile SVG and mobile data transfer, etc., and in accordance with the actual situation of oilfield, the design framework of oilfield mobile GIS service is put forward and the schemes of key technologies are given in this paper, which establishes the technical foundation for the construction of “Digital Oilfield”.
