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51.
代力 《地质与勘探》2013,49(2):236-249
四川夏塞银铅锌多金属矿床位于西南"三江"义敦岛弧构造带中段,是与绒伊措岩体密切相关的浅成中低温热液型银铅锌矿床。对夏塞矿区1号矿体9个中段采样分析,通过数理统计分析、分带序列研究、地球化学参数计算、建立剥蚀模型等方法,系统详细地研究了矿体原生晕地球化学特征。研究表明:(1)1号矿体原生晕找矿的主要指示元素:Ag、Pb、Zn、Cu、Sb、Hg、Cd、Sn,次要指示元素:Bi、W、B、As、Au、Mn;(2)原生晕轴向分带序列为:Hg-Pb-Bi-Sn-Cd-Zn-Cu-As-Ag-W-Au-Sb-Ba-V-Mo-Mn,出现"反分带"现象;(3)成矿过程存在多次叠加,轴向地球化学参数变化曲折,出现多次转折,反应成矿过程复杂。综合各项特征,推测1号矿体深部可能有盲矿存在。  相似文献   
52.
Wave-induced sediment resuspension in nearshore regions has been observed occurring in an event-like manner and associated with the passage of wave groups. This paper describes field measurements of turbulent velocities obtained simultaneously with suspended sediment concentration and water surface elevation from Floreat Beach, Perth, Western Australia. The data were used to study the relationship between turbulent kinetic energy (TKE) on suspension events caused by wave groups and the intermittent nature of bottom turbulence production and sediment suspension. The field measurements showed the high TKE events occurred under wave crests, and sometimes under wave toughs, when the wave heights were increasing during the passage of a wave group; the TKE decreased after the maximum wave in the wave group had passed over the measurement location. High suspended sediment concentrations (ssc) and the intermittent high TKE events were not related rather the higher ssc events were associated with a secondary peak in the surface elevation, close to the maxima in the offshore velocity, and “burst” events in the Reynolds stress.  相似文献   
53.
The reservoir evaluation as a key technology in oil exploration and production is based on the electrical transport property (ETP) of saturated rock that is described in a mathematical form with Arhcie’s equa-tion. But there have been increasing cases observed in many researches indicating that the ETP is non-Archie especially for the complex reservoir with low porosity and permeability. In this paper,the numerical experiments based on the Lattice Boltzmann method (LBM) have been employed to study the effect of porous structure and fluids on the ETP for revealing the nature of non-Archie phenomenon in micro-scale. The results of numerical experiments have proved that the saturation exponent n is a function of water saturation and porosity instead of being a constant in Archie’s equation. And then,a new formula has been developed for the EPT through combining the result of numerical simulation with that of laboratory measurements. The calculations from the new formula show very good agreement with laboratory measurements to demonstrate the efficiency of the new formula over the conventional methods in non-Archie rock.  相似文献   
54.
文中讨论了库水渗漏在水库诱发地震中的作用,经过分析研究现有的水库诱发地震资料及相关理论,类比蒸汽锅炉与重力热管的热工原理,提出了水库地震成因的超临界水二级相变孕震模型。模型在水库孕震的各阶段表现为:初始阶段,渗漏水在压力注射和重力作用下形成水塞密封盖层,在超临界温区的地层裂隙中引发二级相变循环对流;孕育阶段,地层原生裂隙在高围压条件下形成应力腐蚀、化学蚀变、温差应力破碎作用,从而原生裂隙更加发育,制造了更大的对流循环通道;临震突变阶段,在热管下部热交换区内的临界水热通量剧增,超临界水发生横向流动,向封盖层外部扩散;发震阶段,在超临界水重力热管的通量和热管上部交换区所形成的压力,超过地层或封盖层的破坏极限时,推动上部地层做活塞运动导致地震  相似文献   
55.
A class of El Nino atmospheric physics oscillation model is considered. The El Nino atmospheric physics oscillation is an abnormal phenomenon involved in the tropical Pacific ocean-atmosphere interactions. The conceptual oscillator model should consider the variations of both the eastern and westem Pacific anomaly patterns. An El Nino atmospheric physics model is proposed using a method for the variational iteration theory. Using the variational iteration method, the approximate expansions of the solution of corresponding problem are constructed. That is, firstly, introducing a set of functional and accounting their variationals, the Lagrange multiplicators are counted, and then the variational iteration is defined, finally, the approximate solution is obtained. From approximate expansions of the solution, the zonal sea surface temperature anomaly in the equatorial eastern Pacific and the thermocline depth anomaly of the seaair oscillation for El Nino atmospheric physics model can be analyzed. El Nino is a very complicated natural phenomenon. Hence basic models need to be reduced for the sea-air oscillator and are solved. The variational iteration is a simple and valid approximate method.  相似文献   
56.
超临界萃取/气相色谱—质谱测定油页岩中的生物标志物   总被引:4,自引:1,他引:3  
王海霞  饶竹 《岩矿测试》2000,19(2):86-92
采用超临界萃取 /气相色谱 -质谱技术测定了广东茂名油页岩中环己烷的链取代烃、甾烷、甾烯和藿烷等生物标志物 ,其分析结果与经典索式抽提和文献结果基本相符。该方法与索式抽提法相比简单、快速、无污染和危险 ,可用于油页岩等固体样品中生物标志物的分析  相似文献   
57.
超临界流体热力学函数的理论计算   总被引:10,自引:1,他引:9  
孙睿  段振豪 《地质论评》2000,46(2):167-177
Duan等(1992。1996)基于分子间相互作用势能模型,建立了一个适合于超临界流体的状态方程,此方程能反演出世界上几十个实验室测定的成千上万个纯组分及混合物的PVT(压力、体积、温度)数据(温压范围:P〈2GPa,Tc〈T〈2000K)。最近的研究发现,此方程能准确预测H2O、CO2、CH4、N2及它们的混合物在T=1.3Tc,P=0到T=2000K,P=10GPa这一温压范围内的压力、体积、  相似文献   
58.
59.
The U.S. airline network is one of the most advanced transportation infrastructures in the world. It is a complex geospatial structure that sustains a variety of dynamics including commercial, public, and military operations and services. We study the U.S. domestic intercity passenger air transportation network using a weighted complex network methodology, in which vertices represent cities and edges represent intercity airline connections weighted by average daily passenger traffic, non-stop distance, and average one-way fares. We find that U.S. intercity passenger air transportation network is a small-world network accompanied by dissortative mixing patterns and rich-club phenomenon, implying that large degree cities (or hub cities) tend to form high traffic volume interconnections among each other and large degree cities tend to link to a large number of small degree cities. The interhub air connections tend to form interconnected triplets with high traffic volumes, long non-stop distances, and low average one-way fares. The structure of the U.S. airline network reflects the dynamic integration of pre-existing urban and national transportation infrastructure with the competitive business strategies of commercial airlines. In this paper we apply an emerging methodology to representing, analyzing, and modeling the complex interactions associated with the physical and human elements of the important U.S. national air transport and services infrastructure.  相似文献   
60.
地质雷达特征图像与典型地质现象的对应关系   总被引:8,自引:0,他引:8  
地质雷达是浅层地质勘探的有效方法,其对断层破碎带、裂隙带、富水带、岩溶洞穴等不良地质灾害有明显的异常反映。地质雷达测量方式、测线布置及系统参数的选择,可根据测量环境以及探测目标体的大致走向、规模、物性等情况综合分析,做出合理选择。通过用地质雷达对多个工区进行工程勘查,从地质雷达图像的波形、频率、振幅、相位及电磁波能量吸收情况(或自动增益梯度)等细节特征的变化规律出发,建立了典型地质现象与地质雷达特征图像的对应关系,可以作为地质雷达图像解释的重要判据。  相似文献   
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