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11.
苏州富铌钽花岗岩的物质组成及钽的赋存状态研究 总被引:1,自引:0,他引:1
苏州富含铌钽花岗岩 (A型 )由富黑云母花岗岩和富钠长石花岗岩组成。主要副矿物为铌钽铁矿、锆石、细晶石、磷钇矿、黄玉和黄铁矿。钽元素主要形成铌钽铁矿系列单矿物 ,少量分散于长石、石英、黑云母、黄铁矿及萤石中 相似文献
12.
2015年4月25日发生在尼泊尔博克拉MS8.1大地震的深层动力过程与“地中海-喜马拉雅-南亚地震带”的中段喜马拉雅地震活动带密切相关.这次大地震是该地震强烈活动带上长期以来深部物质与能量强烈交换、运动,并导致构造活动和应力积累的产物.综合分析与研究提出:(1)博克拉MS8.1大地震的孕育、发生和发展具有长期活动和近年来相邻地带地震活动频繁的背景;这一地带自1505年-2015年,即500多年来相继发生多次MS≥8.0的大地震.(2)这一地带具有特异的地球物理边界场响应和深层动力过程,显示深部物质的重新分异、调整与能量交换.(3)大地震发生与周边地带应力场分布特异,壳、幔结构与介质属性变异及破裂响应与断层面解的属性相关.(4)喜马拉雅地带的三条北倾断裂带以不同角度向深部延伸、震源位置及浅表层的变形特征尚应深化理解.(5)MS8.1大地震的发生对相邻地带的波场影响强烈,故应强化高精度地球物理场的观测和探测,以“捕捉”未来可能大地震的孕育与发生. 相似文献
13.
Concepts for the Evaluation of Contaminant Mobility in Soil and Waste Materials Elution tests (S4, pHstat, and SDS test) are presented, enabling the evaluation of the mobility of hydrophilic/hydrophobic and inorganic/organic contaminants in soil and waste materials. While elution tests for estimation of the mobilization potential of hydrophilic substances are performed following the pHstat method, for hydrophobic species surfactant-containing eluents are used. The individual parameters of the elution process are selected assuming a "worst-case" scenario. In principle, because of economic reasons, detailed analytical investigations should be preceded by relevant screening tests. 相似文献
14.
在油田开发过程中,隔夹层控制油气水运动规律,对于寻找剩余油具有重要控制作用。本文以N油田TF组2段A油组为研究对象,通过薄片、岩心测试、测井、碳氧同位素等资料综合分析,研究其钙质隔夹层的分布特征、岩石学特征、物性特征、测井识别特征,并从沉积环境、物质来源、成岩作用相结合的角度分析钙质隔夹层的成因。研究表明,A油组纵向上发育的三套钙质隔夹层主要发育在前滨滩坝沉积微相,顶钙与底钙的岩性以砂质生屑质灰岩为主,中钙为钙质砂岩;三套钙质隔夹层中生物碎屑主要以腕足、腹足、有孔虫为主,含少量棘皮、瓣鳃、红藻、介形虫、苔藓虫等;成岩作用主要为胶结作用,胶结物类型包含早期方解石胶结物、中期铁方解石胶结物、晚期铁白云石胶结物;碳氧同位素分析表明,隔夹层中碳主要来自于沉积过程中的海水,同时有少量来自于大气淡水和有机酸,Ca~(2+)主要来源于生物碎屑,其次为钙长石溶解、铝硅酸盐矿物的水化作用。 相似文献
15.
The Zheyaoshan deposit is the largest within the Baiyinchang (BYC) volcanic-hosted massive sulfide (VHMS) district, located in the northern Qilian orogenic belt of North China. The deposit is hosted by quartz keratophyre tuffs, with wall-rock alteration mainly comprising chlorite, sericite, quartz, pyrite and epidote. Mineral assemblages within the altered host rocks can be divided into a sericite-quartz-dominant assemblage (sericite-silicified zone), a chlorite-dominant assemblage (chlorite-dominant zone) and a pyrite-dominant assemblage (mineralized zone) based on geochemical analysis and alteration characteristics. We have conducted detailed processing and critical analysis of the geochemical data of both the altered and least-altered host rocks in order to investigate the problem of closure in the geochemical dataset to eliminate the influence that each component has on the other in terms of mass change, and have applied the standardized method of the mass change calculation to analyze this data. The results show that: (1) the sericite-silicified zone formed along fissures due to the ingress of hydrothermal fluids, with MnO2, Na2O and CaO being mobilized into the hydrothermal fluids leached and MgO, Fe2O3, SiO2, K2O, BaO deposited. Additionally, Ag, Cu and chalcophile elements (Ag, As and Bi) were enriched while Pb, Zn and large ion lithophile elements (LILEs) (Cs, Sr, Eu, Be) were mobilized into hydrothermal fluids; (2) the physiochemical conditions and pH levels of the hydrothermal fluids changed during sericitization, with MgO, Fe2O3, BaO being further enriched and MnO, Na2O, CaO further depleted, leading to formation of chlorite and the initial precipitation of metallogenic the (Cu, Zn, Pb) and chalcophile elements (Ag, As, Bi); (3) the negative Eu anomaly was mainly due to its strong activity when Eu is mobilized into the hydrothermal fluids during since plagioclase break-down during the sericite-silicification process; (4) AI and CCPI values gradually increase towards the orebody. The chlorite-dominant assemblage and sericite-quartz-dominant assemblage on the periphery of the chlorite-dominant zone can all be used as vectors towards the volcanic massive sulfide orebody and for regional-scale mineral exploration. Either leached elements or enriched elements can be considered as significant indicator elements and as prospective indicators for geochemical exploration within the BYC district. The Eu anomaly may be especially useful as an indicator for distinguishing the least-altered rocks which has great significance for exploration on the regional scale. 相似文献
16.
This paper deals with numerical modeling of the compressive behavior of granite rock under high strain rate dynamic loading and wide range of confining pressure. For this end, a constitutive model based on damage mechanics and viscoplasticity for rock is formulated and implemented in explicit dynamics FEM. The viscoplastic part is based on a simple power law type yield criterion that incorporates the rate-dependency with a linear viscosity term. Moreover, a Rankine type of tensile cut-off is employed. The damage part of the model is formulated with separate scalar damage variables in tension and compression. The model is calibrated for Kuru granite and validated with the experimental data from dynamic compression tests at the strain rate of 600 1/s up to 225 MPa of confining pressure. The numerical simulations demonstrate that, despite the underlying continuum modeling approach, the model captures the correct experimental failure modes, including the transition from single-to-multiple fragmentation, as well as the dynamic compressive strengths at different confining pressures. 相似文献
17.
山东省天然饰面石材资源储量大,天然饰面石材品种多,地质成因和地质特征各有不同。通过天然饰面石材的岩石学特征对山东省天然饰面石材进行分类总结,从天然饰面石材的岩石学和矿物学角度出发,归纳山东省天然饰面石材的地质特征。通过对山东省典型天然饰面石材进行分类列举,归纳山东省典型天然饰面石材的地质特征。 相似文献
18.
19.
A fully coupled thermal–hydraulic–mechanical–chemical (THMC) model was proposed to describe the migration of volatile organic contaminations (VOCs) in unsaturated landfill liners. The vertical soil stress, capillary pressure, air pressure, temperature increase, and solute concentration were selected as the primary variables. Finite deformations were described using Lagrangian coordinates. Non-isothermal moisture transport was found to be dependent on both the temperature gradient and the concentration of the VOCs. The VOCs were assumed to exist and be transported in three phases in the soil: solid, liquid, and gas. An illustrative example of an unsaturated landfill with a compacted clay liner was presented. For the case considered, the transport of gas phase VOCs was found to dominate the migration progress. Moreover, the temperature gradient can accelerate the breakthrough of VOCs in an unsaturated liner, while the mechanical consolidation slowed down the motion of the VOCs. 相似文献
20.