Seismic hazard of the Eastern Mediterranean

Earthquake hazard parameters such as maximum magnitude, annual mean seismic activity rate, and the Gutenberg-Richter parameter, have been evaluated for the Hellenic and Cyprean Arc regions of the Eastern Mediterranean. The applied maximum likelihood procedure permits the combination of both historical and instrumental data. The collected data from different sources cover earthquakes with magnitude ≥ 3.5 throughout the last two centuries. The historical part of the catalogue only contains the strongest events, whereas the complete part can be divided into several subcatalogues, each assumed complete above a specific threshold of magnitude. The hazard parameters assessment is performed for the two study regions. The Hellenic Arc region was found to be of higher seismicity level than the Cyprean Arc region. The number of annually expected earthquakes with magnitude ≥ 3.5 is much larger in the Hellenic Arc (56±2) than in the Cyprean Arc (35±2). The maximum magnitude calculated in the Hellenic Arc zone is 7.8±0.4 for the time period equal to the length of the catalogue, i.e., 210 years. For the Cyprean Arc zone, the maximum possible magnitude is 6.8±0.4 for the time span of 330 years.     

A trigger mechanism of nonlinear mechanoelectric conversions in mineralized faults

Polymetallic ores yield evidence of semiconductor textures creating irregularly distributed trap zones of electric charges produced by electrochemical reactions and mechanoelectric conversions. Such zones bounded by natural barriers can contain charges concentrated in separate parts of an ore-bearing province and reside in this state for a long time. If this equilibrium is disturbed, the energy (electric charges) is redistributed and signals of pulsed electromagnetic emission in the radiowave frequency range (PEERFR) are radiated. The set of properties of polymetallic ores recorded under in situ conditions and studied in the laboratory suggests a trigger mechanism of PEERFR signal generation. The triggering threshold of this mechanism depends on mining and geological conditions and the concentration and structure of ores. The energy released in ores can be many times larger than the activation energy of this process.     

Paleomagnetic studies of Paleolithic site deposits in the Matzuka Cave (Northern Caucasus)

As a result of detailed paleomagnetic and magnetic studies of Paleolithic site deposits in the Matuzka Cave, a record of the Matuzka geomagnetic excursion in lithologic layer 7 has been discovered and studied. Such characteristic features as the geomagnetic field direction, position of the virtual geomagnetic pole, geomagnetic field intensity (roughly estimated) after and during the excursion, and climatic conditions coeval with its existence make the Matuzka excursion similar to the ～130-ka Blake excursion. This dates at ～130 ka the formation of layer 7 with ancient archaeological findings.     

用小波包识别地震和矿震

在能检测到天然地震和矿震的区域，这两类地震的快速识别无论对于区域台网和矿区台网都具有现实意义。这两类震动都是非稳态信号，用传统的Fourier变换不能提取出信号的特征信息，小波包分析方法却能很好提取出信号的特征信息。本文提供了一种基于非参数识别算法，即把信号变换到频域，然后再用奇异值分解作为统计工具，提取出信号的特征信息，作为识别天然地震和矿震的识别因子。以辽宁抚顺2001年1月1日到2003年6月30的18个矿震和16个天然地震，以及北京门头沟2001年1月1日到2002年12月31日的15个矿震和14个天然地震为样本，提取出识别因子。最后，用其它的天然地震和矿震资料检验了识别因子的识别率。     

基于数值预报产品的温度释用方法比较

为了选取适当的预报方法,运用于业务预报工作中的客观要素预报,我们以ECMWF数值预报输出产品为基础,对卡尔曼滤波(Klm)、最优子集回归(OSR)和岭回归(RR)三种方法针对温江、宜宾、内江、达县2005年6～7月的温度预报进行了探讨.结果表明:在样本完全相同的情况下,三种预报方法效果相当,但从运行速度来看,RR最快,Klm 其次,OSR 最慢;在预报方法相同而样本长度不同的情况下,样本长度为60天的预报效果较好.     

利用掌上电脑开发水准测量记簿软件

采用嵌入式程序设计的方法,在掌上电脑开发水准测量记簿软件,使野外观测数据记录更加方便。本文详细介绍了该程序的设计构思和一些技术问题。     

An objective classification system of air mass types for Szeged, Hungary, with special interest in air pollution levels

Summary This paper determines the characteristic air mass types over the Carpathian Basin for the winter (December, January, and February) and summer (June, July and August) months dependant on levels of the main air pollutants. Based on the ECMWF data set, daily sea-level pressure fields analysed at 00 UTC were prepared for each air mass type (cluster) in order to relate sea-level pressure patterns with the level of air pollutants in Szeged. The data comprise daily values of twelve meteorological and eight pollutant parameters for the period 1997–2001. Objective definition of the characteristic air mass types is achieved by using the methods of Factor Analysis and Cluster Analysis. According to the results, during the winter months five air mass types (clusters) were detected based on higher concentrations of primary pollutants that occur with high irradiance and low wind speed. This is the case when an anticyclone is found over the Carpathian Basin and over the region south of Hungary, influencing the weather of the country. Low levels of pollutants occur when zonal currents exert influence over Hungary. During the summer months anticyclones and anticyclone ridge situations are found over the Carpathian Basin. (During the prevalence of anticyclone ridge situations, the Carpathian Basin is found at the edge of a high pressure centre.) As a result of high irradiance and very low NO levels, secondary pollutants are highly enriched.     

桃仙机场雷雨转雨夹雪天气的分析

通过对桃仙机场仅有的两次雷雨转雨夹雪天气过程的分析，总结出此类天气的形势特点，并初步得出此类天气预报的着眼点，为秋季飞行提供可靠的预报保障。     

青藏铁路唐古拉山-拉萨段全新世控震断裂研究

地表调查表明,沿青藏铁路唐古拉山-拉萨段存在5条重要的全新世控震断裂带,从北到南分别是温泉盆地西缘断裂带、安多盆地北缘断裂带、崩错断裂带、谷露西缘断裂带和当雄-羊八井断裂带.构造-地貌和年代学分析结果表明,北部的温泉盆地西缘断裂和安多盆地北缘断裂带的活动强度相对比较小,平均垂直活动速率约为0.2～0.5mm/a.南侧的谷露西缘断裂带和当雄-羊八井断裂带的全新世垂直活动速率为约(15±0.5)mm/a.而中部的崩错走滑断裂带的活动强度最大,晚第四纪期间的走滑速率可达(11±4.5)mm/a.全新世断裂活动和古地震研究表明,其中温泉盆地西缘断裂带、安多盆地北缘断裂带、崩错断裂带的西北分支、当雄-羊八井断裂带的当雄段等区域未来发生强震的概率相对更大.     

天津市堆山造景工程地基稳定监测与防治

堆山造景工程是一项利用建筑渣土,在坑塘上进行堆载的市政工程。通过对堆山造景工程的工程地质条件分析,结合工程设计、施工工期等条件,提出了清理淤泥、设置反压平台、排水、控制堆填速率等促进地基稳定的防治措施。利用孔隙水压力监测、侧向位移监测及分层沉降监测等原位监测数据,以复合型法进行反演力学计算参数,并将反演结果用于该工程地基稳定性的模拟,以指导后期工程以及类似工程的建设。