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951.
山西地区的地壳应力场 总被引:4,自引:1,他引:4
根据近20年山西地区的震源机制结果,得出了山西地壳应力场存在着有别于华北应力场的局部小区域应力场,这种小区域应力场在中部断陷盆地都是以北西—北北西向的水平拉张作用为主,而在东、西两侧隆起区则是以水平挤压作用为主的结论.但如果把上述断层面解中的所有P轴、T轴再分别投影到吴尔夫网上,得到是一个一致性很好的断层面解,由此推断山西地区的平均应力场的主要特征与华北应力场的基本特征完全相同,而山西局部小区域应力场的特征随之消失. 相似文献
952.
953.
Characteristics of melt inclusions in skarn minerals from Fe,Cu(Au) and Au(Cu) ore deposits in the region from Daye to Jiujiang 总被引:5,自引:0,他引:5
The skarns and skarn deposits are widely distributed at home and abroad. The skarn deposits include many kinds of ores and higher ore grade. Some of them are broad in scale. Scientists of ore deposits from different countries have paid and are paying grea… 相似文献
954.
Lateral load pattern in pushover analysis 总被引:9,自引:2,他引:7
The seismic capacity curves of three types of buildings including frame, frame-shear wall and shear wall obtained by pushover
analysis under different lateral load patterns are compared with those from nonlinear time history analysis. Based on the
numerical results obtained a two-phase load pattern; an inverted triangle (first mode) load pattern until the base shear force
reachesβ times its maximum value, Vmax, followed by a (x/H)α form, hereβ and α being some coefficients depending on the type of the structures considered, is proposed in the paper, which can provide
excellent approximation of the seismic capacity curve for low-to-mid-rise shear type buildings. Furthermore, it is shown both
the two-phase load pattern proposed and the invariant uniform pattern can be used for low-to-mid-rise shear-bending type and
low-rise bending type of buildings. No suitable load patterns have been found for high-rise buildings. 相似文献
955.
REE mobility during hydrothermal ore-forming processes has been extensively investigated in recent years and the potential of REE to provide information about ore forming processes has commonly been recognized.The Dongping gold deposit,which is located in northwestern Hebei Province,China,occurring in the inner contact zone of the Shuiquangou syenite complex,is spatially,and probably genetically,related to the syenite,the deposit was formed under the moderate to high temperature(220℃ to 320℃),weakly acidic to weakly alkaline,rather high fo2(lgfo2=-30~-34)environment.The REE study of the host rocks,altered wall rocks,ores and gangue minerals from the deposit suggests that the REEs have been mobilized and differentiated during K-feldspathization and silicification.The extremely altered syenite enveloping auriferous quartz vein shows positive Ce anomaly and larger LREE/HREE ratio than that of the unaltered syenite.The REE concentrations and patterns of the ores are determined by the ore types and mineral assemblages,LREE/HREE ratios in the gangue quartz and hydrothermal Kfeldspars are relatively low.The most significant observation is that the gangue quartz shows significant positive Eu anomaly,whereas the hydrothermal K-feldspars show less significant or no positive Eu anomaly at all relative to the primary feldspar in the unaltered syenite. It is evident that the REEs are mobile during K-feldspathization and silicification in the ore forming process.Weak to moderate K-feldspathization caused REE mobility without apparent differentiation with the exception of extreme K-feldspathization and silicification which resulted in significant depletion of HREE and Eu and relative enrichment of Ce.The REE,Y,U,Th and Au contents of the syenite decrease as the degrees of K-feldspathization and silicification of the rocks increase towards the auriferous quartz veins.As the ores were deposited under a rather oxidized environment,Ce^4 predominated over Ce^3 .The precipitation of the former in the form of CeO2 or absorpted onto the secondary mineral assemblage resulted in the inconsistent removal of the REE and the relative Ce enrichment in the strongly altered rocks.in contrast,Eu was present mainly in a low valence state (Eu^2 ).The geochemical differences from the other REE^3 and much less sites in the secondary minerals to accommodate the Eu released form the original minerals resulted in the enrichment of Eu in the fluids.The mobility and differentiation of REE and the coherent mobilities of Y,U,Th and Au also support the argument that the syenite is one of the source rocks for gold mineralization.The REE contents and patterns of the altered rocks enveloping the auriferous quartz vein could be used as a guide for locating ore veins in mineral exploration. 相似文献
956.
Research on scale effect of histogram 总被引:2,自引:0,他引:2
To describe the spatial relationship among the earth objects compactly, in this paper, we raised the concept of histo-variogram
based on the analysis of the characteristics of other spatial analyzing methods such as variogram, information entropy. And
we also raised a new spatial analysis method of histogram decomposition based on the definition of standing pixel and contour
pixel. At the end of this paper, we demonstrated the characteristics of histo-variogram by two experiments, one for spatial
analysis, the other for image fusion. 相似文献
957.
山西义兴寨金矿床金矿物颗粒的产出及其成矿动力学意义 总被引:1,自引:0,他引:1
山西义兴寨金矿床的金主要呈包体金和裂隙金两种产出状态.文章根据成矿地球化学动力学理论,论证了金元素在含矿断裂发生脆性破裂和脆-韧性扩张活动中析出的化学反应类型,以及受反应动力学条件的制约,形成矿石中金不同产出状态的规律.指出热液矿床中普遍存在的包体金为热液成矿早期阶段断裂发生脆性破裂和成矿流体沸腾,导致快速反应结晶的产物;而裂隙金和晶隙金为成矿晚期金等矿质在流体中残余富集,同时成矿断裂再次发生脉动破裂,即成矿热力学演化与有利的构造动力学因素耦合作用的结果.得出金矿物颗粒的产出状态具有成矿动力学意义的结论. 相似文献
958.
Volume Contents
Contents To Volume 88 相似文献959.
纤粒矿物粉尘体外细胞毒性研究 总被引:6,自引:0,他引:6
采用体外细胞培养技术,观察兔肺泡巨噬细胞死亡率,用丙二醛(MDA)的含量变化、乳酸脱氢酶(LDH)及超氧化物歧化酶(SOD)的活性变化来评价来自12个矿6床的6种矿物的12种结晶习性的矿物粉尘的细胞毒性,探讨其使巨噬细胞受损的机制。结果显示:沸石、硅灰石无细胞毒性,而其他的纤维状及片粒状矿物粉尘则表现出不同程度的细胞毒性,说明矿物粉尘的细胞毒性与矿物粉尘的形态有一定关系,但主要由矿物粉尘的特性所决 相似文献
960.
数字测绘技术在城镇地籍测量中的应用 总被引:1,自引:0,他引:1
通过实例简述了数字化测绘技术在城镇地籍测量中作业流程、实施过程与地籍管理信息系统的建立过程。说明用该技术作业效率与成果精度比较高。 相似文献