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261.
Fluidization: An Important Process in the Formation of the Qiyugou Au-bearing Breccia Pipes in Central China 总被引:2,自引:0,他引:2
ZHANG Yuanhou ZHANG Shihong Franco PIRAJNO 《《地质学报》英文版》2007,81(2):226-238
Fluidization processes based on experiments are reviewed to gain some useful insights and comparisons with those that occur in hydrothermal systems. Field and petrographic work, and microscope observation were carried out on samples from the Qiyugou Au-bearing breccia pipes from the East Qinling region, Henan Province. Evidence from macro- and micro-textures suggests that the style of breccias in the Qiyugou area can be grouped into three types: (1) jigsaw fit-stockwork texture, in which the interval between clasts is marked by fractures or filled with calcite or quartz veins; (2) larger breccias that are supported by smaller breccias, rock flour and alteration materials; in this type clasts moved over short distances, creating open spaces; (3) fluidized texture, where the clasts of different lithologies have rounded shapes. These observations are compared with those resulting from experiments on fluidization processes. The results of this comparison suggest that fluidization is an important geological process in the formation of the Qiyugou Au-bearing breccia pipes and gold mineralization. In addition, fluidization processes such as expansion, bubbling, slugging, channeling and spouting must have contributed to the formation of the pipes and were conducive to the development of gold mineralization. In the Qiyugou breccia pipes, gold mineralization occurs as disseminations, in stockwork veins, and open space infills. The ore zones form subparallel sheets that are nearly perpendicular to the walls of the pipes. 相似文献
262.
Discovery and Significance of High CH4 Primary Fluid Inclusions in Reservoir Volcanic Rocks of the Songliao Basin, NE China 总被引:2,自引:0,他引:2
WANG Pujun HOU Qijun WANG Keyong CHEN Shumin CHENG Rihui LIU Wanzhu LI Quanlin 《《地质学报》英文版》2007,81(1):113-120
Comparing compositions of the fluid inclusions in volcanic rocks to the contents and isotopes of the gases in corresponding volcanic reservoirs using microthermometry, Raman microspectroscopy and mass spectrum analysis, we found that: (1) up to 82 mole% methane exists in the primary inclusions hosted in the reservoir volcanic rocks; (2) high CH4 inclusions recognized in the volcanic rocks correspond to CH4-bcaring CO2 reservoirs that are rich in helium and with a high ^3He/^4He ratio and which show reversed order of 813C in alkane; (3) in gas reservoirs of such abiotic methane (〉80%) and a mix of CH4 and CO2, the enclosed content of CH4 in the volcanic inclusions is usually below 42 mole%, and the reversed order of δ^13C in alkane is sometimes irregular in the corresponding gas pools; (4) a glassy inclusion with a homogeneous temperature over 900℃ also contains a small portion of CH4 although predominantly CO2. This affinity between gas pool and content of inclusion in the same volcanic reservoirs demonstrates that magma-originated gases, both CH4 and CO2, have contributed significantly to the corresponding gas pools and that the assumed hydrocarbon budget of the bulk earth might be much larger than conventionally supposed. 相似文献
263.
Alkali Mohammed 《东北亚地学研究》2008,(4)
This research studies the reliability of an activated carbon permeable reactive barrier in removing cadmium from a contaminated shallow aquifer.Laboratory tests have been performed to characterize the equilibrium and kinetic adsorption properties of the activated carbon in cadmium-containing aqueous solutions.A 2D numerical model has been used to describe pollutant transport within a groundwater and the pollutant adsorption on the permeable reactive barrier(PRB).In particular,it has been considered the case... 相似文献
264.
Yuejun CHEN Chunlin SUN Yuewu SUN Research Center of Palaeontology & Stratigraphy Jilin University Changchun China 《东北亚地学研究》2008,11(3):145-149
Jianshanzi volcanic rocks at Qinghe valley in the northern Liaoning were considered belonging to Early Proterozoie Gaojiayu Formation of Liaohe Group, or to Early Cambrian Beidagou Formation of Qinghezhen Group, or Middle-Late Proterozoic Shenjiapu Formation-Complex of Kaiyuan Group-complex. Dating the zircons from the dacite with schistosity is 2 506 Ma in method of U-Pb (SHRIMP). This evidence indicates the rocks may be referred to Late Permian in age. Discovery of the rocks is significant to re-recognize stratigraphic property of "Liaohe Group", regional geoteetonie location and revolution of orogenic zone in Qinghe valley of the northern Liaoning. 相似文献
265.
Jihua HU Yanjun ZHANG Danyan DU Gang WU Ziwang YU Chen WANG Fuquan NI. College of Construction Engineering Jilin University Changchun China. College of Environment Resources China. College of Information Engineering Sichuan Agricultural University Ya 'an Sichuan China 《东北亚地学研究》2008,11(3):182-187
Energy utilization in the aquifers is a new technology closely related to development of heat pump technique. It is significant for the flow distribution to be predicted in the aquifer surrounding the Groundwater Source Heat Pump System (GSHPS). The authors presented a new concept of "flow transfixion" by analyzing general features of aquifers, and then discussed interaction of the flow transfixion with the beat transfixion, which has practical significance to projects. A numerical model of groundwater flow was established based on the basic tenets of water-heat transferring in the aquifer. On this basis the flow field and the temperature field of GSHPS for a site in Shenyang City were numerically simulated. The basis of the flow transfixion was obtained; it was discussed for the influence of the flow transfixion on the heat transfixion. To a certain extent, the study offers some reference for the projects' design of GSHP in the studied area. 相似文献
266.
Chengdong QI Guohua QIAO Hongchen DONG Dayei LUI Xing ZHANG Deli YU .Regional Survey of Geology & Mineral Resources Jilin Province Changchun China.College of Material Science Engineering Jilin University Changchun China 《东北亚地学研究》2008,11(4):214-217
LA-ICP MS zircon U-Pb dating results of granites from Sawuer Mountains in North Xinjiang, NW China, are reported based on 1:50 000 regional geologic surveys. Zircon U-Pb dating shows that the granitoids have magmatic crystallization age of 320 ± 2 Ma. In addition, zircons with ages of 341 -358 Ma could be subdivided into two groups, i. e. , Group 1 with a weighted mean age of 342 ± 3 Ma and Group 2 with a weighted mean age of 354 ± 2 Ma. The petrology and geochemistry of granitoids from Sawuer Mountains suggest their mixed origin. The granite from Sawuer Mountains occurred in an extensional setting, most probably related to post-orogenic processes during the closure of the Peo-Asian Ocean ; namely, represent the tectonic setting shifted from compress to post-collisional setting. 相似文献
267.
Dajun ZHAO Guosheng JIANG Youhong SUN Junhua ZHENG Zhuwen WANG .Faculty of Engineering China University of Geosciences Wuhan China.College of Construction Engineering Jilin University Changchun China.College of Geoexploration Science Technology China 《东北亚地学研究》2008,11(4):228-231
A high efficiency method is very important in geological survey for a new city in China. Geophysical parameters are Measured While Drilling (MWD), and these parameters are processed and explained on the ground, so the method can replace conventional engineering geological exploration for drilling rock sample. According petroleum engineering MWD, using the different characters of different rock absorbs γ radial, with the method of storing data in hole and explaining data on the ground, engineering geological exploration formation density MWD is researched. The MWD works stabilized, and the performance is good with precise data. 相似文献
268.
Qinghua WANG Youhong SUN Qiang LI College of Construction Engineering Jilin University Changchun China 《东北亚地学研究》2008,11(4):237-241
A mobile in-situ testing equipment used to detect geotechnical thermophysical properties was developed. The equipment is composed of a heat pump, frequency pumps, an electric tee joint regulator valve, some sensors, an electric control system, data acquisition and control system, which can do tests under the condition of extracting and storing subsurface heat. Applying the line source and the cylinder source heat transfer model, and combining the parameters estimation, the average thermophysieal property parameters of rock and soil will be calculated, which provides the basis for designing the ground source heat pump systems. 相似文献
269.
Xujun LI Zhenyan LUO Xue CHEN College of Earth Sciences Jilin University Changchun China 《东北亚地学研究》2008,(3)
The gold deposits in the Jiudian gold field in the southwestern part of the Jiaodong terrane are much similar, but less attention-paid ones than those in the northwest part of the same terrane. The ore-controlling faults in the Jiudian gold field could be classified into three types: fluid transporting; fluid dispatching and fluid precipitating. The fluid precipitating faults are usually small and low-order ones, and could be fatherly classified into three types based on their orientation: NE-, NNE-and NW o... 相似文献
270.
Stability is always the most important problem after high slope was excavated. The study analyzed the stress and strain inside the slope by Finite Element Method (FEM) and carried through stress distribution and failure zone, then analyzed the stability of the slope using three different methods and came to the conclusion that it is in unstable condition, so the designed retaining wall was put forward which makes the slope stable. 相似文献