诱发地震中的非双力偶震源   总被引：1，自引：0，他引：1  

杨清源  陈献程 《地震地磁观测与研究》1994,15(1):1-5

在诱发地震的研究中，用小孔径地震台网在近场观测，其震源机制的Ｐ波初动除Ⅲ象限分布的双力偶外，还有不是Ⅲ象限分布的非双力偶震源机制。双力偶震源机制是剪切破裂机制。非双力偶震源机制为向内源炸型和张破裂机制，以及在适当方向上两个以上双力偶迭加的结果。  相似文献   

中国人皮肤相对湿度的地理分布   总被引：3，自引：0，他引：3  

毛政旦 《气象》1994,20(8):12-16

根据Ｂｅｒｇｌｕｎｄ等人（１９８３）公式：Ｗ＝（ｅｓｋ－ｅａ）／（ｅｓｓｋ－ｅａ），利用大气温度，大气水汽压和皮肤温度的月平均值，计算皮肤相对湿度，并按皮肤相对湿度划分舒适带。结果表明，决定我国皮肤相对湿度地理分布的基本因素是纬度，海陆分布，地形和大气环流，季节不同，则各因素所起作用有差异。作者以皮肤相对湿度２５％－４５％表示舒适带，计算表明，我国气候舒适带有明显的地区差异和季节变化。  相似文献   

Physicochemical Conditions of the Formation of Beryl and Aquamarin in Mufushan Granopegmatite Deposit,Hunan Province,China     

李兆麟  牛贺才等 《中国地球化学学报》1994,13(4):326-339

The formation of the Mufushan granopegmatite was closely related to the Late Yenshanian multiphase and multistage magmatic activities,More than one generation of beryl and aquamarine occur in different types of pegmatite in the granites.The presence of melt and melt-fluid inclusions strongly indicates a melt-solution character of the pegmatitic magma.Forming temperatures of the different generations of beryl in a Na^ -K^ ,Ca^2 -CO3^2--Cl^--SO4^2- solution ranges from 990℃to 200℃.Aquamarine was formed at 720-180℃.The contents of alkali metals(Na^ K^ )in th ore-formming solution of aquamarine are lower than those in the beryl,but the contents of alkali earths(Ca) and salinity are higher,The granite was generated by remelting of the basement formation(meta-sedimentary rocks of the Lengjiaxi Group)which also served as the source of ore-forming material.Beryllium in the pegmatite was transported mainly in the form of Na[Be(CO3)2],with part of it being complexed with Cl^- and SO4^2-.During the generation and evolution of the pegmatite,equilibrium might have been reached in the solid-melt-fluid or solid-fluid system.The intergranular solutions may have reacted with the early crystallized minerals,resulting in potash-feldsparization,albitization and muscovitization during which the ore-forming elements were mobilized and transported in favour of ore deposition.  相似文献   

点源两层大地三维地电模型视电阻率边界元解   总被引：2，自引：1，他引：2  

毛先进  钱家栋 《地震工程学报》1994,16(1):1-11

本文用两层均匀大地人工点源作用下的空间电位分布作为基本解，导出了下伏基岩中陷含三维地质体情况下，关于电位的边界积分方程组，用边界单元法解积分方程求得地表电位，从而求得了一定装置下的视电阻率。本文方法的独特优点是积分只须在异常体边界面上进行了测线可以沿任意方向。用联剖法计算了均匀半空间下含球形异常体的ρｓ曲线，所得结果与其他学者用解析方法所求得的结果一致。用中间梯度法计算下层基岩中含有一长方体，测线  相似文献   

我国大气污染物远距离传输的估计——Ⅰ:轨迹分析   总被引：4，自引：1，他引：4  

盛裴轩  毛节泰 《气象学报》1987,45(1):65-71

根据1979年1,4,7和10月的1500m高度的测风资料,利用二维流场,计算了通过北京、西安、兰州等10个城市空气块的轨迹。依据轨迹及其终点的分布讨论了不同季节对上述这些城市有影响的污染物的来向及以这些城市为源地的污染物的远距离输送问题。  相似文献   

Raman spectrum of natural and synthetic stishovite     

R. J. Hemley  H -K. Mao  E. C. T. Chao 《Physics and Chemistry of Minerals》1986,13(5):285-290

Raman spectra of natural and synthetic samples of stishovite have been measured with a micro-optical spectrometer system. These spectra have a pattern that is characteristic of rutile-structured oxides. The spectrum of synthetic stishovite is characterized by well-resolved bands at 231, 589, 753, and 967 cm^?1, which are assigned as theB _1g,E _g,A _1g, andB _2g fundamentals, respectively, of the first-order Raman spectrum of the ideal, ordered structure. Natural stishovite obtained from Meteor Crater, Arizona has a first-order Raman spectrum that is fully consistent with that of the synthetic material. The observed spectrum of the natural sample, however, is weaker and has bands in addition to those identified as fundamentals in the spectrum of the synthetic material. A broad band at ～475 cm^?1 may be indicative of glass or contaminants derived from the extraction procedure. Alternatively, this band may arise from multiphonon scattering that is enhanced by poor crystallinity or structural disorder in the natural shocked sample.  相似文献   

The Evolutionary History of Ore-forming Processes of Metallic Ore Deposits in Northern Guangxi     

Chen Yuchuan  Mao Jinwen  Wang Ping''an Chinese Academy of Geological Sciences  Beijing Fei Zhenbi 《《地质学报》英文版》1995,69(2)

The northern Guangxi region is an important rare metal, rare earth metal and polymetallic metallogenic province. In the region there exist five metallogenic series and two metallogenic subseries, whose metallogenesis shows features of polycyclic spiral evolution throughout the geological history. As far as various cycles are concerned, mantle-derived ore substances were reduced while crust-derived ore substances increased from early to late timesfin the whole geological evolutionary history, mantle-derived substances decreased gradually while crust-derived ones increased. Meanwhile ore element associations became more and more varied. In terms of space, mineralization migrated from the old basement outwards, i.e. from west to east during the Precambrian, and from north to south during the Phanerozoic, and again from east to west during the Yanshanian.  相似文献   

有限区域短期数值预报业务系统简介          下载免费PDF全文

茅卫平  马华平  郭卫东  李振军 《气象》1995,21(4):37-42

简要介绍了空军气象中心投入业务使用的《空军有限区域短期数值预报业务系统》的概况、采用的主要技术，检验评分结果，最后给出了天气学个例检验结果。  相似文献   

电子探针分析与系列矿物研究   总被引：2，自引：0，他引：2  

毛水和 《矿物学报》1987,(2)

本文论述以电子探针为主要测试手段对下述几种系列矿物的研究成果:(1)铂族元素系列矿物的研究(包括Ru-Os-Fe金属互化物矿物系列和RuAs_2-OsAs_2二元固溶体矿物系);(2)Au-Cu系列矿物的研究;(3)黝铜矿族矿物的研究。  相似文献   

应用图象识别法预测强震危险区存在的问题及讨论          下载免费PDF全文

毛卫民 《地震工程学报》1982,4(4):120-123

应用图象识别法预测强震危险区虽然国内外都有报道,但也还存在一些问题,近来国内已有人发现,用图象识别法确定地震危险区存在一些缺陷,它直接影响到结果的可靠程度。为了进一步从理论上搞清产生这些问题的根源及其规律,下面我们就两类图象识别问题的数学模型,根据线性不等式组的理论进行严格的数学讨论。  相似文献