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101.
上海地区扁铲侧胀试验计算地基承载力的探讨 总被引:1,自引:1,他引:1
通过对扁铲侧胀试验和试验机理的研究和对试验指数的对比分析 ,提出了用扁铲侧胀试验计算地基承载力的方法 ;利用上海地区部分重大工程中的扁铲侧胀试验数据 ,在与室内土工试验、静力触探试验及十字板剪切试验的相关分析的基础上 ,经数理统计后给出了上海地区用扁铲侧胀试验计算地基承载力的经验公式。最后 ,通过与室内土工试验、静力触探试验和十字板剪切试验计算的地基承载力对比 ,分析了本经验公式计算地基承载力的精度。研究分析表明 ,可以用扁铲侧胀试验计算地基承载力 相似文献
102.
本文通过联剖、电测深、磁法和测温法等综合工作成果,分析、推断出汤上屯热水构造的产状、性质和热水出露条件,圈定出了热水分布范围. 相似文献
103.
Geometric form of Haiyuan fault zone in the crustal interior and dynamics implications 总被引:1,自引:0,他引:1
The deep seismic reflection data on profile HY2 are reprocessed by the method of simultaneous inversion of velocity distribution
and interface position. By the travel-time inversion with the data of the diving wave Pg and fault plane reflection wave,
we determine the geometric form and velocity of Haiyuan fault zone interior and surrounding rock down to 10 km depth. The
measured data show that the amplitudes have strong attenuation in the range of stake number 37–39 km, suggesting the fault
zone has considerable width in the crustal interior. The results of this paper indicate that to the north of the fault zone
the crystalline basement interface upheaves gradually from southwest to northeast and becomes shallow gradually towards northeast,
and that to the south of the fault zone, within the basin between Xihua and Nanhua mountains, the folded basement becomes
shallow gradually towards southwest. The obliquity of the fault zone is about 70° above the 3 km depth, about 60° in the range
of the 3–10 km depths. From the results of this paper and other various citations, we believe that Haiyuan fault zone is in
steep state from the Earth’s surface to the depth of 10 km.
Foundation item: Joint Seismological Science Foundation of China (201001) and State Key Basic Research Development and Programming Project
(95-13-02-02).
Contribution No. RCEG200308, Exploration Geophysical Center, China Earthquake Administration. 相似文献
104.
105.
106.
Methane-rich fluid inclusions in skarn near the giant REE–Nb–Fe deposit at Bayan Obo, Northern China
We report fluid inclusion data for skarn, formed at the contact between Hercynian granitoids and dolomite of the Proterozoic Bayan Obo Group, in the vicinity of Bayan Obo REE–Nb–Fe deposit, Inner Mongolia, China. Three types of fluid inclusions are identified: two-phase CH4-rich, three-phase liquid–vapour–solid and two-phase aqueous inclusions. Using microthermometry and laser Raman microprobe analysis to calculate isochores for CH4-bearing inclusions, we estimate fluid trapping conditions at T=280 to 344 °C and P<1 to 2.3 kbar. Such conditions are compatible with formation of CH4 inclusions as a result of reaction between graphite in the country rocks (black slate sequence) and fluids derived from magma. The lack of carbonaceous material in the inclusions supports the hypothesis that CH4 was generated during fluid migration rather than by in situ reaction. In contrast to the skarn, and despite the fact that similar graphite-bearing slates are found in the host rocks, no CH4-bearing inclusions have been so far reported from Bayan Obo REE ores. We therefore conclude that the skarn-forming fluids in the contact aureole of the Hercynian granitoids were not involved at any stage in the formation of the Bayan Obo deposit. 相似文献
107.
108.
在信息传播媒体的竞争日益严酷的时代,面对天气预报节目只依靠简单的画面加解说,拉洋片式传统方法这样一种一成不变的局面,策划创意制作出《天气资讯》节目,打破天气预报节目以往的节目形式和播出形式,以极少的投入获得最大的社会效益和经济效益。 相似文献
109.
On the basis of an experimental study and thermodynamic calculation, the mechanisms of paragenesis and separation of silver, lead and zinc in the hydrothermal system have been studied. At acidic to nearly neutral pH, their chloride complexes are stable, and among them the chloride complexes of zinc are most stable. And the sulfide complexes are the dominant species at nearly neutral to alkaline pH,while the sulfide complexes of silver are most stable. With decreasing temperature, [ Cl^-] ,fO2, and increasing pH, the solubilities of silver, lead and zinc will decrease, leading to their deposition and separation. For sulfide complexes, the concentrations of reduced sulfur and pH are two important factors affecting their stabilities. Complexes of different forms and stabilities respond to the variation of conditions to different extents, which gave rise to the paragenesis and separation of silver, lead and zinc in the whole ore-forming process of dissolution, transport and deposition. 相似文献
110.
简要回顾了岩石圈均衡理论的发展及岩石圈区域均衡和挠曲理论在岩石圈动力学研究中起的作用,阐述岩石圈有效弹性厚度(Te)的概念和特征。强调Te的研究是地质学和地球物理学的紧密结合,即通过岩石圈挠曲理论和区域均衡原理,对地形和重力资料进行谱分析计算,来获取岩石圈的物理性质信息。计算的Te(和相应的挠曲刚度)是岩石圈等效的强度,与爆破地震、地震层析成像和大地电磁测深等方法观测到的岩石圈和地壳厚度不同,它们之间只有通过岩石圈的屈服刚度包络面(YSE)才能比较。大洋和大陆岩石圈YSE的理论计算,表明Te值显著小于地震学的地壳和岩石圈厚度。尤其对于大陆岩石圈,地壳厚度、热年龄和应变率均可显著影响岩石圈的强度。本文还以滇西为实例介绍了对相干值曲线计算的新认识和当前岩石圈Te研究的最新趋势。 相似文献