火山碎屑空降沉积的二维数值模拟

从大气中火山灰扩散的二维微分方程出发 ,采用Suzuki(1983)对火山空降碎屑灾害数值模拟的数学模型 ,研制出用于单个火山一次性喷发事件的碎屑物空降沉积分布的实用程序。介绍了编程的基本思想 ,讨论了编程过程中所遇到的实际问题 ,同时结合长白山火山物理研究工作给出的长白山火山动力学参数 ,对长白山火山喷发空降碎屑厚度分布进行了具体模拟应用 ,针对实际模拟结果对程序提出了改进意见 ,并对Suzuki火山碎屑空降沉积模型进行了讨论     

福州盆地晚第四纪地层划分及古环境分析

基于福州盆地古田路附近 2个试验钻孔所揭示的地层岩性的系统分析和 2孔 4 3个热释光样品的年龄结果 ,以及对其中 1个钻孔 72个孢粉样品的系统分析结果 ,对钻孔所揭示地层的沉积相和沉积时序进行了讨论 ,划分了地层的沉积时代 ,恢复了沉积物沉积时的古气候环境     

负坡段加卸载响应比的物理意义及预测效能

根据实验结果，用应变能研究岩石在极值应力后主破裂前（负坡段）加卸载响应比可能出现奇异点或负值的变化特征，并且说明其普遍性．以应变（能）及Ｐ波走时为响应，分别得出加卸载响应比的倒数在岩石破裂孕育过程中的变化形态．结果表明:在逼近主破裂时，加卸载响应比的倒数急剧下降后出现极小值（甚至为负值）．此特征可以看作临近主破裂的标志．      

Isotopic Geochronological Evidence for the Caledonian Xiongdian Eclogite in the Northwestern Dabie Mountains,China

A typical HP/MT (high pressure/medium temperature) eclogite from Xiongdian, northwestern Dabie Mountains, has been geochronologically studied using the single-zircon U-Pb, 40Ar-39Ar and Sm-Nd methods. Prismatic zircons occurring as inclusions within garnets define a minimum crystallization age of 399.5±1.6 Ma. 40Ar-39Ar dating on amphibole gives a plateau age.of 399.2 ± 4 Ma, which is interpreted as a retrogression age of amphibolite facies. This integrated study enables us to conclude that the age of high-pressure metamorphism is older than 399.5 ± 1.6 Ma, suggesting Caledonian collision between the North China and Yangtze plates. Round zircon within the aggregate of quartz and muscovite gives a concordant age of 301± 2 Ma, reflecting a later retrogression event. An age profile of post-eclogite metamorphism is documented, including amphibolite facies metamorphism at 399.2 Ma shortly after eclogitization and later retrogressive metamorphism at 301 Ma. Sm-Nd mineral isochron of garnet+omphacite gives     

潜水位观测频率优化探讨

运用统计学方法，以潜水位的时间序列为基础，通过对该序列的一阶，二阶统计量分析，确定估计的置信区间宽度与观测数之间的关系，在此基础上，根据观测精度的要求设定的置信区间宽度来确定最佳观测频率。     

Time-space evolution characteristics of abrupt variation of wave velocity ratio in the seismogenic process of recent strong earthquakes in Yunnan area

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1976年唐山7.8级地震前各类地震前兆异常信息熵的场,源兆特征

利用“专家系统”的思想对每一地震前兆异常事件进行了综合评估，以每一异常的最可能发震时间计算发震概率，利用各类地震前兆异常群体信息熵研究了系统熵值与地震场，源兆的关系，分析了１９７６年唐山７．８级地震前各类地震前兆异常的时空分布特征，然后以唐山为中心在空间上划分三个区，近区，中间区和远区，分别计算了三个区各类地震前兆异常信息熵的时间演化值，分析了震前这种信息熵的场，源兆特征，震中近区的信息熵值要比中     

短波电台对地震仪干扰机理分析及抑制方法

对短波电台发射时干扰地震仪的机理进行了分析。指出干扰形式及干扰噪声进入地震仪的端口，用抗干扰三要素理论结合地震台、站实际条件，采用低通网络抑制干扰，收到了明显的效果     

The application of ultrasonic seismic model experiment in quality test of cement mortar injection of Yongjiang river submarine tun－nel tube foundation

ＴｈｅａｐｐｌｉｃａｔｉｏｎｏｆｕｌｔｒａｓｏｎｉｃｓｅｉｓｍｉｃｍｏｄｅｌｅｘｐｅｒｉｍｅｎｔｉｎｑｕａｌｉｔｙｔｅｓｔｏｆｃｅｍｅｎｔｍｏｒｔａｒｉｎｊｅｃｔｉｏｎｏｆＹｏｎｇｊｉａｎｇｒｉｖｅｒｓｕｂｍａｒｉｎｅｔｕｎ┐ｎｅｌｔｕｂｅｆｏｕｎｄ...     

Earthquake-Generating Structure During the Period of the 1992 Sichuan Lima Earthquake Sequence

In this paper,a test or alternative scheme for studying large earthquake sequences through the study of small earthquake sequences is suggested,and a small earthquake sequence,the Lima earthquake sequence for which analogue records have been turned into digital data,is used here.In order to provide the deep construction background and the spatial distribution of structure for generating earthquakes,the P-wave and S-wave layered velocity models in this area are obtained by using mine explosion and earthquake observed records; then,the hypocenter locations and focal depths of the Lima earthquake sequence are determined adopting the velocity models given above and using a location method with numerical properties for a microseismic monitoring network(Zhao et al.,1994)and a new method for determining focal depth from data of a local seismographic network(Zhao,1992); finally,based on this,the variation of quality factor Q of the crustal medium during the period of the sequence is estimated.The obtained resul