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1.
介绍了泸沽湖地震台静水位观测受到定时干扰及数据处理人员和仪器维修人员查找干扰原因、排除干扰、让静水位观测数据恢复正常的过程.  相似文献   
2.
The seismic hazard assessment of the Dead Sea rift, Jordan   总被引:1,自引:0,他引:1  
The Dead Sea fault system and its branching faults represent one of the most tectonically active regions in the Middle East. The aim of this study is to highlight the degree of hazards related to the earthquake activities associated with the Dead Sea rift, in terms of speculating the possible future earthquakes. The present investigation mainly is based on available data and vertical crustal modeling of Jordan and the Dead Sea model for the Dead Sea basin with particular emphasis of the recent earthquake activities, which occurred on December 31st, 2003 (Mc = 3.7), February 11th, 2004 (strongest Mc = 4.9 R), and March 15th, 2004 (Mc = 4). The present research examines the location of the strong events and correlates them with the various tectonic elements in the area. The source mechanism of the main shock and the aftershock events is also examined. The analyses were based on the available short period seismogram data, which was recorded at the Natural Resources Authority of Jordan, Seismological Observatory. The seismic energy appears to have migrated from the south to the north during the period from December 31st up to March 12th, where the released seismic energy showed a migration character to the southern block of the eastern side of the Dead Sea, which led the seismic event to occur on March 15th.  相似文献   
3.
烟台海域海岛自动站大风对比试验   总被引:2,自引:0,他引:2  
烟台北部面临黄、渤海,海岛自动站分布众多.我们发现,在同一大风过程中,各海岛自动站的风速、风向因为海拔高度、周围地形影响、下垫面摩擦的不同造成明显差异.本文主要以长岛作为渤海海峡大风的代表站,以崆峒岛和芝罘岛作为烟台北部沿海海域大风的代表站,利用便携自动站的观测数据近似代表海面大风的实况,与代表站进行大风的对比试验,对比试验的数据均采用指数廓线公式订正到海面10m高度.分析了三个海岛自动站的不同风向下的海面大风的实际代表性,并给出不同风向下的大风订正值.  相似文献   
4.
地震与核爆识别的小波包分量比方法   总被引:20,自引:5,他引:20  
频谱分析法在核爆与地震识别中具有广泛的应用.但是频谱分析方法是稳态方法,即使采用Gabor变换,也因时-频窗口形状不变而分辨串较低.为提高时-频分辨率,本文将小波变换理论用于乌鲁木齐台记录的地震与核爆事件的分析,并提出了识别核爆和天然地震的小波包分量比判据.通过对加拿大黄刀地震台记录的印度地下核爆的分析,进一步验证了小波包分量比判据对核爆和地震的识别具有较高的识别效率.结果表明:对于地震信号,其小波包分量比U03/U1一般都大于1.0,而对于核爆信号,比值U03/U13一般都小于1.0.  相似文献   
5.
The remote sensing observational study for infrared radiation of rocks was proceeded during the loading on rocks until failure. The major instruments used in experiments were transient spectrum apparatus, intelligent spectrum apparatus, infrared radiation thermometer, infrared spectrum radiometer, and infrared thermal imaging system. The experiments for 26 kinds of rocks were made. The studies show that infrared radiation temperature of rocks increases along with increasing of stress. The amplitude of infrared radiation spectrum of rocks also increases along with increasing of stress. The observational results of infrared thermal imaging of rocks are consistent with infrared radiation temperature. Before formation of major faults for some rocks, the belt-shape thermal imaging of temperature anomaly displaies in position of future major faults. This study has led the new technology of remote sensing into rock mechanics and tend to establish a new field in rock mechanics — remote sensing rock mechanics (or remote sensing rock physics). The application of remote sensing rock mechanics in prediction of earthquake and rock burst, and in measurement of stress field in rock mass is expected. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,14, Supp., 645–652, 1992. Jin-Shen HAO, Ji-Han LI, Xiao-Hong LIU, Yi-Qiao ZHI, Jin-Kai ZHANG, Yong-Hong Lü, Yi LIU, Yun-Shen YU, He ZHANG, Quan-Quan JI, Xiao-Fan ZHU and Ning CHEN took part in this work. This subject is supported by the Chinese Joint Seismological Science Foundation (91006). Work of Institute of Geophysics, SSB (93A0009).  相似文献   
6.
本文采用大森公式n(t)=K/(t+c)^p求解K、c、p三个参数,对云南1965年以来71个地震序列进行研究。确定P=0.8为前兆震群和正常震群的判定指标。利用K、c、p三参数计算序列理论曲线得到晚期强余震前差残曲线超出两倍均方差的结果。  相似文献   
7.
介绍下关34井气氡测点及资料对应地震情况,针对2007-2010年气氡观测资料几乎每年相同时段出现的高值异常现象,结合该井水温、降雨、湿度、水位及可能出现的影响因素分析,认为异常可能是由于湿度和集气容积随水位变化与地震前兆异常叠加的结果,为判别气氡异常提供参考和借鉴,以利于提高气氡观测质量及在地震分析预报中的应用.  相似文献   
8.
The paper presents a method of estimating parameters in two competitive functional models. The models considered here are concerned with the same observation set and are based on the assumption that an observation may result from a realization of either of two different random variables. These variables differ from one another at least in the main characteristic (for example, outliers can be realizations of one variable). A quantity that describes the opportunity of identifying a single observation with one random variable is assumed to be known. That quantity, called the elementary split potential, is strictly referred to the amount of information that an observation can provide about two competitive assumptions concerning the observation distribution. Parameter assessments that maximize the global elementary split potential (concerning all observations), are called M split estimators. A generalization of M split estimation presented in the paper refers to the theoretical foundation of M-estimation. An erratum to this article can be found at  相似文献   
9.
    
After the occurrence of the 26 September 1997 earthquake in Umbria–Marche an extensive survey was performed to individuate surface effects induced by the ground motion. Several types of effects occurred on bedrock, calcareous debris and sandy-clay deposits. Shallow soil slides and dry debris slides were mapped by field survey and aerial photograph interpretation in the epicentral area close to Nocera Umbra. This gave the opportunity for testing the prediction maps that can be obtained with the use of empirical laws, proposed by several authors, based on a simple method (Geotechnique 15(2) (1965) 139). Accelerometric records from the permanent and mobile seismic network of the Seismic Survey of Italy have been processed and interpolated to obtain strong ground motion parameters at each site, e.g. Peak Ground Acceleration, Spectral Intensity, Arias Intensity, etc. The different predictions have been tested with the real landslide data to verify their performances. Some of the proposed methods explain quite well the behaviour of slopes during the application of a time history and can therefore be employed for future landslide hazard zonation.  相似文献   
10.
Evaluation of seismic ground motion induced by topographic irregularity   总被引:1,自引:0,他引:1  
Results of an extensive numerical study on the 2D scattering of seismic waves by local topography are presented. The investigation has been conducted using the direct boundary element method. Several types of topography (slopes, canyons and ridges) are considered. The influences of some key parameters, such as exciting frequency and geometry of the irregular feature, on surface ground motion are studied in detail. It is found that local topographic conditions play an important role in the modification of seismic ground motion at the irregular feature itself and its neighbourhood. The present results can be considered to be useful from the viewpoint of earthquake engineering and seismology.  相似文献   
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