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991.
Natural Hazards - In the freeze–thaw zone of the eastern Sichuan–Tibet Mountains, the phases of water in cracks show strong seasonal variations, which significantly affect the stability... 相似文献
992.
Wang Xiangqian Li Yingming Zhao Chengxing Wang Yi Huang Shunjie 《Geotechnical and Geological Engineering》2021,39(8):5931-5942
Geotechnical and Geological Engineering - In order to reveal the mechanism of surrounding rock deformation and instability of soft rock roadway in 12# working face of Puhe coal mine, and... 相似文献
993.
Geotechnical and Geological Engineering - The second phase of the Chongqing Rail Transit Line project has poor rock and soil stability, slow construction progress, complex and variable geological... 相似文献
994.
Acta Geochimica - The Sandaowanzi gold deposit is an extremely Au-rich deposit in the Northern Great Hinggan Range in recent years. Zircon U–Pb geochronology, Hf isotope analysis, and the... 相似文献
995.
Landslides - Identifying and tracking the potential avalanche types is the first step toward characterizing an avalanche problem and a fundamental principle of effective avalanche risk management... 相似文献
996.
Zhong Wenhan Liu Hanlong Wang Qi Zhang Wengang Li Yongqin Ding Xuanming Chen Longlong 《Acta Geotechnica》2021,16(6):1849-1865
Acta Geotechnica - Snake can perfectly utilize its scales to move. Inspired by the snake scales, this study investigated the characteristics of the snake skin-inspired pile penetration process. Six... 相似文献
997.
Shangbin Chen Zhuo Gong Xueyuan Li Huijun Wang Yang Wang Yingkun Zhang 《地学前缘(英文版)》2021,12(6):192-208
Fine characterization of pore systems and heterogeneity of shale reservoirs are significant contents of shale gas reservoir physical property research.The research on micro-control factors of low productivity in the Qiongzhusi Formation(Fm.)is still controversial.The lower Cambrian Qiongzhusi Fm.in the Qujing,Yunnan was taken as the object to investigate the influence of mineral compositions on the phys-ical properties of the reservoir and the heterogeneity of shale,using the algorithm to improve the char-acterization ability of Atomic Force Microscopy(AFM).The results showed that:(1)The pores are mainly wedge-shaped pores and V-shaped pores.The pore diameter of the main pore segment ranges from 5 to 10 nm.Mesopores are mainly developed in the Qiongzhusi Fm.shale in Well QD1,with the average pore diameter of 6.08 nm.(2)Microscopic pore structure and shale surface properties show strong hetero-geneity,which complicates the micro-migration of shale gas and increases the difficulty of identifying high-quality reservoirs.(3)The increase of clay mineral content intensifies the compaction and then destroys the pores.Conversely,brittle minerals can protect pores.The support and protection of brittle minerals to pores space depend on their content,mechanical properties and diagenesis.(4)Compression damage to pores,large microscopic roughness and surface fluctuations and strong pore structure heterogeneity are the reasons for the poor gas storage capacity of the Qiongzhusi Fm.,which will lead to poor productivity in the Qiongzhusi Fm. 相似文献
998.
Acta Geotechnica - Complex geological conditions and/or inappropriate shield tunnel boring machine (TBM) operation can significantly degrade both the excavation and safety of tunnel construction.... 相似文献
999.
Acta Geotechnica - Suffusion is a typical form of internal erosion for gravel soils in which fine particles are detached by seepage and transport by water through pores. The prediction of erodible... 相似文献
1000.
通过小波分析和频谱分析,发现Z分量低点时间的小波变换结果曲线(α=6)明显地随节气而变化;对地磁Z分量低点时间季节性变化进行了初步的比较分析. 相似文献