内蒙古东乌珠穆沁旗至辽宁东沟地学断面综合地球物理特征   总被引：2，自引：1，他引：2  

卢造勋  夏怀宽  赵国敏  张国臣  董宝中  孟补在  李平 《东北地震研究》1993,(2)

综合地球物理探测与研究是地学断面的重要内容和基本依据,本断面的综合地球物理研究表明:这里的地壳可分为上、中、下三层,在某些部位中层地壳可进一步分为两层,其上层在断面东南端的辽河断陷东侧及燕山台褶带的义县、朝阳地区呈现为低速层;地壳厚度在断面东南端薄,为31—35km,而在西北端厚,达38—40km;辽河裂谷东侧存在壳内高导层,整个断面上地幔高导层发育,在辽河断陷及朝阳、义县地区反映为上地幔隆起区,在西拉木伦河一带出现落差达50km左右的台阶;确认析木断裂、郯—庐断裂北段、朝阳—北票断裂、赤峰—开原断裂和西拉木伦河等断裂为壳幔深断裂;发现海城地区、朝阳—北票地区及西拉木伦河地区为地壳与上地幔结构异常区,这里也正是地震较活跃的地区。  相似文献   

山西地震带历史地震序列的统计分析   总被引：2，自引：0，他引：2  

彭美煊 《地震》1993,(5):40-46

在工程地震工作中需要知道某地震带或某地区未来100年内的地震活动水平,以便适当选择历史地震的统计时段,从而得到和地震活动水平相适应的不同潜在震源区的各级地震的年平均发生率。 本文利用极值理论、最大熵原理、马尔可夫模型的方法、莫尔纳方法和伯努里模型方法计算了山西地震带未来100年内中强震的年平均发生率、平均重现期大于等于某级地震的个数和发震概率,计算结果表明,山西地震带未来百年内将发生≥6.0级地震3次,发震概率为0.94左右;将发生≥6.5级地震1—2次,发震概率为0.84左右;有可能发生≥7.0级地震,发震概率为0.53左右;发生≥7.5级地震的可能性不大,发震概率为0.32左右;发生≥8.0级地震的可能性很小,发震概率为0.15左右。  相似文献   

三维非均匀地幔中深源电场和磁场的谱理论(Ⅰ)——基本耦合方程组     

马石庄  徐升  陆文松 《地球物理学进展》1993,(2)

地球深部研究(SEDI)已经揭示出地幔中的温度和密度在大尺度下的三维非均匀结构,而地幔的电性结构是敏感地依赖于地幔的热状态的.对由地球发电机产生的非定常深源电场和磁场,在三维非均匀地幔中的扩散问题作3系统的探讨.根据球面矢量场的Helmholtz 分解定理,将支配的Maxwell 方程组分解为位势场Φ、环型场T 和极型场S 的基本耦合偏微分方程组,并利用张量球谐函数展开,得到该方程组的谱表示.以此,作为进一步研究核幔电磁耦合理论的必要基础.  相似文献   

断裂带的韧-脆性转化与成矿   总被引：1，自引：0，他引：1  

彭恩生 《地球物理学进展》1993,(4)

根据河南西部绿岩型脉状金矿的一些地质现象,探讨了韧性剪切带转化为脆性断裂的机制.韧性剪切过程岩石的面理化为矿液参与断裂作用,增加流体压力创造了条件.流体压力的增加一方面可以改变断裂的力学性质;另一方面可以压裂围岩,促进断裂韧-脆性转化,为脉状矿床的形成创造了条件.  相似文献   

CCD相机二维几何检校     

陶闯  林宗坚  卢健 《武汉大学学报(信息科学版)》1993,(4)

CCD 相机检校是 CCD输入影象处理的一个必不可少的过程。本文对 CCD成象系统的几何性能进行了分析,提出了测定 CCD影象象素比例因子和象主点初值的简易实验方法。在此基础上,构造了一种同时顾及光、电误差的二维检校方法,井进行了相机检校实验。最后对检校结果进行了分析和讨论。  相似文献   

点、线符号相关处理的代数方法   总被引：2，自引：0，他引：2  

胡鹏  游涟  陈成永 《武汉大学学报(信息科学版)》1993,(Z1)

本文阐述了采用地图代数的理论自动地处理各类地学信息系统编绘地图中点、线符号相关问题的技术方法——交会运算。  相似文献   

Li3N·LiI·LiCl锂快离子导体研究          下载免费PDF全文

贾永忠  杨金贤 《盐湖研究》1993,1(4):67-70

采用固态反应的方法制备Li_3N·LiI·LiCl快离子导体样品。使用X—射线衍射分析和差热分析的方法进行物相鉴定。电化学性能测试结果表明,样品具有较高的离子电导率,在100℃,其电导率可达10~(-4)_s/cm量级。样品的电导率与温度的关系很好地遵循Arrhenius方程。测得样品的电导活化能E_a为0.45eV。  相似文献   

Geochemistry of dissolved and particulate elements in the major rivers of China (The Huanghe,Changjiang, and Zhunjiang rivers)   总被引：1，自引：0，他引：1  

C. H. Qu  C. Z. Chen  J. R. Yang  L. Z. Wang  Y. L. Lu 《Estuaries and Coasts》1993,16(3):475-487

The relationship between the geochemistry of dissolved and particulate materials and geographic conditions was investigated. Samples of water and suspended particulate matter were collected from five locations in three of the major rivers of China (the Huanghe, Changjiang, and Zhunjiang rivers). Because these rivers generally flow parallel to latitudes and flow through diverse geologic and climate zones, they provide excellent opportunities for comparisons of solute transport. The geochemistry of these rivers is influenced strongly by climate. The low discharge of the Huanghe River influences the character of the major ionic materials (Cl^?+SO₄ ^2? and Na⁺+K⁺) as well as the high degree of mineralization within the system. Dissolved concentrations of both major ions and trace elements are lower in the southern reaches of the rivers. The highly mobile ions, such as, Na⁺ and Ca²⁺, are depleted from the suspended particulate material in the southern regions, while the relatively immobile ions of Al, Fe, Ti, Mn, and trace metals are concentrated within the suspended mateiral. The relative mobility of some elements as measured by the Dissolved Transport Index (DTI) changes with climate. The geology of the area drained by the rivers has a major influence on the geochemistry in areas of similar climate. Lowest leaching rates in the southern climates occur in areas dominated by granite, which is resistant to weathering. The composition of both cations and anions among the three tributaries of the Zhujiang River are dependent on the rocks that dominate each eregion. Some particulate forms of the rare earth elements are present in the highest concentrations in regions dominated by granite. The DTI calculated for the major rivers in China are much smaller than those computed for other major rivers of the world. The low concentration of heavy metals in the particulate material suggests that pollution in the rivers of China is less serious than in rivers of other industrialized countries.  相似文献   

Negative Haloes and Geochemical Field Systems of Hydrothermal Deposits1     

Ji Kejian  Wang Liben  Lu Fengxiang  Wang Wuyi  Zhang Jianhua 《《地质学报》英文版》1993,6(2):195-209

Abstract Primary haloes of hydrothermal deposits were previously considered as positive haloes. Although it has been recently suggested that primary haloes incude positive and negative ones, almost all the research work on primary haloes has still focused on positive haloes for various reasons. In order to understand the source of ore substances a number of large hydrothermal deposits related to magmatism including porphyry, skarn and vein type deposits have been studied. It has been found that negative haloes exist on the peripheries of positive haloes of a mineral deposit. On the basis of the study the authors propose the concept of the geochemical field system of ore-forming elements of hydrothermal deposits, i. e., with the orebody as the centre outwards there occur the mineralized field, positive halo field, depleted field and background field successively.  相似文献   

STATISTICAL ANALYSIS OF CYCLONE TRACKS IN WESTERN ANTARCTIC REGION          下载免费PDF全文

Chen Shanmin  Zhang Linyu  Lu Changgui 《Acta Meteorologica Sinica》1990,4(1):74-80

The paper shows the statistical analysis of cyclone tracks that have influence on the western Antarcticregion.Based on the conditions of cyclone movement and its impact upon the weather,cyclone tracks areclassified into three categories,i.e.,the track moving towards the northern tip of the Antarctic Peninsula,southern track,and northern track.Moreover,in this paper,the frequency distributions of cyclone tracks,the major tracks with higherfrequencies,the original region of Antarctic cyclones and the seasonal features of Antarctic cyclones have beenanalyzed.The results show that there are higher cyclogeneses in summer,whereas relatively fewer cycloge-neses in winter,and cyclone numbers in transitional seasons are close to the climatological average.Theanalysis also shows that the moving velocity of Antarctic cyclone is about the same in winter and summer.It obviously speed up during the transitional season.  相似文献