岩石颗粒解离试验研究     

汪兴模 《矿物岩石》1990,10(1):103-106

试验确定，在用HCI和NaOH试剂解离硅质胶结的沉积岩时，浓度5％的试剂即可达到解离度95％以上，且颗粒表面特征、重矿物数量和重矿物标型特征较浓度10％的试剂处理的样品保存得更好。  相似文献   

非理想热力学混合作用对固溶体矿物热容的影响——以斜方顽火辉石-正铁辉石固溶体为例     

沙连堃 《矿物学报》1991,(1)

斜方顽火辉石-正铁辉石(MgSiO_3-FeSiO_3)中Fe~(2+)及Mg~(2+)在M_1和M_2两种非等效位置上进行非理想混合。研究表明,辉石的等压热容(C_p)强烈依赖于组成,呈非线性关系,可表示为: 低温时热容的非理想混合效应显著,随着温度的升高,等温热容曲线(空间热容曲面)从一个极大值点(峰脊)分解为两个极大值点(峰脊),且逐渐趋向于理想混合热容直线(或平面)。  相似文献   

法国Echassieres地区石英网脉中黑钨矿及其共生矿物的固溶体研究   总被引：1，自引：0，他引：1  

王汝成 《岩石矿物学杂志》1991,10(4):369-378

Echassiares石英网脉中的黑钨矿主要系钨锰矿一钨铁矿系列中的铁端员矿物一钨铁 矿，富泥但贫担，当其与妮铁矿共生时，钨铁矿可含8.91% Nb205。在该矿物中常见的元素置换 有:(1)Fe2+→Mn2+;(2)Wg6+Fe2+→Nb5+ +Fe+3 (3) 3W6+ +Fe2+ →4Nb5+。 妮铁矿呈它形，富含Ta. W,Ti。钨铁捉矿以枝状形态位于钨铁矿和妮铁矿之间，形成完整的矿物组合。Beauvoir花岗岩的侵位带入的热液交代钨铁矿是形成这种矿物组合的主要原因。同时,铅钨铁矿中的裂隙带或其边部还局部发生钨锰矿化。  相似文献   

华北强震断层面解和震源深度特征   总被引：17，自引：1，他引：17       下载免费PDF全文

汪素云 Ni  J 《地球物理学报》1991,34(1):42-54

本文利用远震P波及SH波和区域地震P_(nl)波波形反演方法,测定了华北9次强震的断层面解、震源深度及地震矩.结合其他作者测定的7次地震的结果,分析了华北16次强震断层面解及华北地震震源深度特征.结果表明,华北多数强震为走滑型地震,也有个别正断层型及逆断层型地震;16次地震多数发生在地壳中部10-25km深度范围内.  相似文献   

鱼眼全景立体像对解析处理的微分公式     

李广文  李伟倩 《测绘学报》1991,20(4):295-302

  相似文献   

一类超线性椭圆方程组解的存在性     

于锦海 《测绘学院学报》1991,(2)

本文研究半线性椭圆方程组在Ω中以及Dirichlet边界条件u|Ω=V|Ω=0的解的存在性.其中Ω是R~n中光滑有界开集。关于非线性项f(x,u)作超线性假设。在此假设下,若f满足增长限制|f(x,u)|≤a|u|°=b,其中a、b、σ是常数.1<σ<(n+2)/(n-2),则利用临界点方法.证明了(*)+b,其中a、b、σ是常数,1<σ<(n+2)/(n-2),则利用临界点方法.证明了(*)有古典解存存。这样不用对(*)的解作先验估计,解决了Figueiredo和Mitidieri在[2]提出的问题。  相似文献   

Pressure Solution of Sulphides in Some Massive Sulphide Zinc—lead Deposits of Western Canada：Its Significance in Mobilization of Ore—forming Materials   总被引：2，自引：0，他引：2  

顾连兴  ANDK.R.MCCLAY 《中国地球化学学报》1994,13(2):132-141

Pressure solution is a common phenomenon in massive sulphide zinc-lead deposits of western Canada and may have been an important factor leading to the mobilization of ore-forming materials during diagenesis, deformation and metamorphism of sedimentary ores.The control of ductile shear zones over gold mineralization could be explained in view of pressure solution of gold-bearing miner-als under shearing stress and the tesultant mobilization of this metal.  相似文献   

软岩巷道弹塑性变形的理论分析   总被引：16，自引：0，他引：16  

刘夕才  林韵梅 《岩土力学》1994,15(2):27-36

本文采用莫尔－库仑屈服准则和非关联塑性流动法则分析了轴对称软岩巷道的变形规律。从轴对称平面应变问题的基本方程出发，导出了软岩巷道弹塑性变形的位移理论解答，并给出了现有应力与位移理论解的适用条件。通过实例计算结果表明，本文得出的位移理论解与有限元数值解相当吻合。  相似文献   

Nonequilibrium thermodynamics of pressure solution     

F. K. Lehner  J. Bataille 《Pure and Applied Geophysics》1984,122(1):53-85

This paper is concerned with the thermodynamic theory of solution and precipitation processes in wet crustal rocks and with the mechanism of steady pressure-solution slip in contact zones, such as grain-to-grain contacts, fracture surfaces, and permeable gouge layers, that are infiltrated by a mobile aqueous solution phase. A local dissipation jump condition at the phase boundary is fundamental to identifying the thermodynamic force driving the solution and precipitation process and is used here in setting up linear phenomenological relations to model near-equilibrium phase transformation kinetics. The local thermodynamic equilibrium of a stressed pure solid in contact with its melt or solution phase is governed by Gibbs's relation, which is rederived here, in a manner emphasizing its independence of constitutive assumptions for the solid while neglecting surface tension and diffusion in the solid. Fluid-infiltrated contact zones, such as those formed by rough surfaces, cannot generally be in thermodynamic equilibrium, especially during an ongoing process of pressure-solution slip, and the existing equilibrium formulations are incorrect in overlooking dissipative processes tending to eliminate fluctuations in superficial free energies due to stress concentrations near asperities, defects, or impurities. Steady pressure-solution slip is likely to exhibit a nonlinear dependence of slip rate on shear stress and effective normal stress, due to a dependence of the contact-zone state on the latter. Given that this dependence is negligible within some range, linear relations for pressure-solution slip can be derived for the limiting cases of diffusion-controlled and interface-reaction-controlled rates. A criterion for rate control by one of these mechanisms is set by the magnitude of the dimensionless quantityk/2C _pD, wherek is the interfacial transfer coefficient, is the mean diffusion path length,C _p is the solubility at pressurep, andD is the mass diffusivity.  相似文献   

Diffusion models of slope development     

A. M. Trofimov  V. M. Moskovkin 《地球表面变化过程与地形》1984,9(5):435-453

This paper represents a systematic investigation of slope evolution diffusion models and has the following sections: (1) The model of slope development with linear coefficient k = k₀x; (2) The model of slope development with quadratic coefficient in x; (3) Slope development model with vertical lowering of base level (downcutting); (4) Slope development model with the base level a horizontal variable (undercutting); (5) Steady-state regime of undercut slopes; (6) Model of a pediment and scree slope formation. The comparison is made between mathematical and classical methods of slope evolution analysis.  相似文献