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rock in underground engineering. Key words: catastrophe progression method; underground engineering; surrounding rocks; stability classification 地下工程围岩稳定性分类是评定围岩性质,判断地下工程稳定性的前提,是进行工程设计和制定相应工程措施的重要依据... of surrounding rocks 2.2 地下工程稳定性影响因素分类标准 根据相关行业规范及国外分级经验,采用5级分类,选取RQD,Rw,Kv和Kf和ω作为具体分类指标,各单因素分类指标标准见表1. 表1 围岩稳定性分类标准 Table 1 Stability classification standards for surrounding rock......
:<正>In this paper we present petrology and geochemistry from a range of metasomatically altered rocks within the Eastern Gawler Craton mineralised province of South Australia.The rocks represent four protolith types;granite,basalt,non-carbonate metasediment and calc-silicate metasediment.Alteration paragenesis varies in intensity and between......
, China) Abstract:The characteristics of rare earth elements in the Devonian and Carboniferous volcanic rocks were studied in the north Altay. And the mechanism of formation of volcanic rocks were... and Carboniferous volcanic rocks, and the mechanism of formation of volcanic rocks may be the partial melting. The further study of the relationship of manifold rare earth elements shows......
to characterize the ore samples and their wall rocks in three ore zones in order to reveal the origin of ore-forming materials and fluid. In AuI, REE chondrite normalized patterns of ore are similar to those... and AuIII are similar, and most of the ore samples are similar with the wall rocks. The ore-forming fluids of AuII and AuIII were metamorphic hydrothermal fluids which had extracted ore-forming materials......
to characterize the ore samples and their wall rocks in three ore zones in order to reveal the origin of ore-forming materials and fluid. In AuI, REE chondrite normalized patterns of ore are similar to those... and AuIII are similar, and most of the ore samples are similar with the wall rocks. The ore-forming fluids of AuII and AuIII were metamorphic hydrothermal fluids which had extracted ore-forming materials......
deformation at large deformation section of Baozhen tunnel. Key words: saturated soft rocks; rock volume change; compressive test; second liner rocks[M]. Beijing: Science Press, 2002: 12-26. [7] GB 50218-94, 工程岩体分级[S].GB 50218-94, Grading standard of engineering rock mass[S]. [8] PouyaA, GhoreychiM......
赣中周潭群变质沉积岩的微量元素地球化学研究 刘丛强1,胡恭任2,于瑞莲2 (1.中国科学院,地球化学研究所,贵州,贵阳,550002;2.华侨大学,环境科学与工程系,福建,泉州,362021;3.东华理工大学,核资源与环境教育部重点实验室,江西,南昌,330013) 摘要:对赣中周潭群变质沉积岩及其石榴子石等造岩矿物的稀土元素地球化学进行了详细研究.结果表明:造岩矿物只携载了岩石中少部分稀土元素,而大部分稀土元素赋存在副矿物的晶格中;变质过程中稀土元素在石榴子石变斑晶与岩石间达到了分配平衡,石榴子石/岩石间的稀土元素分配明显受体系化学组成所制约;变质岩脉及其矿物的稀土元素组成显示清楚的四......
渤海湾盆地三叠系沉积厚度恢复及其意义 秦勇1,姜波1,李田忠1,朱炎铭1,范炳恒1 (1.中国矿业大学 资源与地球科学学院,) 摘要:综合运用现代油气地质理论及镜质组反射率测定等现代分析测试方法,分析了渤海湾地区的构造演化及古地温场特征；采用EASY%Ro数值模拟技术对大量钻孔进行了埋藏史反演,首次较为细致合理地恢复了渤海湾地区三叠系原始沉积厚度.结果表明:华北晚古生代巨型沉积盆地的发育历史一直延续至印支中期,古生界在印支期末埋藏可达2500~4000m,埋藏深度及其在空间上的展布特征主要受控于三叠系的原始沉积厚度. 关键词:数值模拟; 镜质组反射率; 三叠系; 古生界; [全文内......
Dynamic Magma Conduit System Related to the Jinchuan Ni-Cu Sulfide Deposit, NW China () 摘要: The Jinchuan Ni-Cu sulfide deposits, NW China, are hosted in small ultramafic intrusions that were emplaced into Paleoproterozoic metamorphic rocks. The ultramafic intrusions were previously thought to be the segments of a single elongate intrusion that was dismembered by late faults into eastern......
of heavy metals(V,Pb,Cd,Cr,and As) from stone coal waste rocks with various particle sizes using dynamic leaching experiments.The results show that the dissolved concentrations of V and As initially... rocks strongly influenced the heavy metal concentration in the leaching solutions.The effects of the particle size of the stone coal waste rocks on the dissolved concentrations of V,Pb,and As decreased......
