震兆图象的远程遥联性

通过研究我国一些震情窗口成组震兆与大陆及边邻Ms≥7.0级地震的整体链式活动的对应关系,指出这些窗口的成组震兆具有远程遥联的特点。对这种特点的深入研究将有可能为我国大陆及边邻地区地震活动的总体大形势作出估计。     

汾渭地震带的地震活动性

根据历史强震与现代地震的资料,研究、分析了汾渭地震带强震及中、小地震的时、空、强分布特征,对该带未来地震危险性进行了探讨。     

On the seismic regime network method

In this paper, based on the previous study of practical use of seismic regime windows and seismic regime belts, the problem of establishing a “seismic regime network” consisting of “windows” and “belts” is further posed and discussed according to the observed fact that many “windows” and “belts” make responses to one earthquake. For the convenience of usage, the “seismic regime network” is divided into two classes, the first class and the second one. The former can be used in tendency prediction for long-term seismic activity in a large area, the latter used in short-term prediction in a small area. In this paper, after briefly discussing the physical significance of “seismic regime network”, it is pointed out that this simple and easily used method can be used to observe and extract seismic precursory information from a large area before a great earthquake, thus it can provide a reliable basis for the analysis and judgement of seismic regime tendency in time and space. No doult, this method is of certain practical significance. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 161–169, 1991. The English version of this paper is improved by Prof. Shaoxie Xu.     

The expert system for earthquake prediction (I)—the overall design and main structure

The Expert System For Earthquake Prediction (ESEP) is summarized in this paper. ESEP embraces three subsystems: long-middle term prediction system, annual prediction system and middle-short term prediction system. Each of the subsystems is composed of seven modules: the controlling module, the data base module, the expert knowledge base module, the method base module, the fact preparation module, the reasoning and decision-making module and the plotting and displaying module. The reasoning model ESEP/R and the knowledge expression model ESEP/K are set up in the ESEP, and new evidence combinations, CON (confine), W (weigh), and SYN (synthesize), have been proposed. The distinctive features of the ESEP are: (1) systemized; (2) several experts’ knowledge can be synthesized; (3) a large amount of data and experts’ experience is embraced; (4) four reasoning models and the synthetic decision-making technic are adopted; (5) several software environments are used; (6) modularization; and (7) possessing the friendly user interfaces. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,14, 1–8, 1992.     

The experimental research on b value of AE for the rock specimens with pre-existing crack or notch under uniaxial compression

A lot of researches onb value have been made in seismology. Since the 1960’s Mogi, Scholz and others have studied AE of rock specimens in laboratory and discovered that it is related to natural earthquakes. All former researchers used integral specimens to studyb value in the laboratory. However a major earthquake is usually related to a existing seismic-fault in that area. For this reason, a series of fracture experiments with rock and glass specimens having pre-existing crack or notch is performed in order to examine the effect of preexisting crack tob value. The experimental results show that theb value begins to decrease as soon as the initiation of the crack and finally drop to a very low value when the specimen breaks unstably. Based on these, a brief discussion on the possible mechanism ofb value change for natural earthquakes is given. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,9, 393–400, 1987. Projects sponsored by the Chinese Joint Seismological Science Foundation.     

Statistical analysis of seismic data from north-western and western Argentina

Due to the process of subduction of the Nazca Plate, high seismic activity is observed near the Argentine Andean range between 21°S and 36°S. The new version of the Argentine Seismic Catalogue, which includes well-defined events during the period 1964–1989, allows us to perform an analysis of seismic risk.Earthquakes with epicenters in the provinces included in the north-western and western regions were studied using Gumbel III extreme value distribution. Modal extreme magnitudes and return periods were calculated for both regions and the results were compard with the ones obtained through the entire process techniques (both analytical and graphical).As a first study, we analyzed each province separately, after which mean values for each region were obtained. Modal values around 5–5.5 have been found and times of recurrence for events withm _b >6 of approximately 25 years were obtained.Also at CONICET (Consejo Nacional de Investigaciones Cientificas y Técnicas).     

用地震折射法探测沥青路面的季节融化深度及其变化

试验结果表明,用经过数字化改造后的地震仪测出的路心融化深度,与钻孔测温确定的融化深度相比,其解释误差小于7％。路基和涵洞横剖面的探测结果能反映出融化层变化的主要趋势。不同路堤高度的路基形成的融化横剖面均呈下凹形,而涵洞下形成的融化横剖面则是涵洞中心的融化深度小于两端洞口处的融化深度。因此,地震折射法将为多年冻土地区路基的修筑和稳定性研究提供一种简捷、可靠的探测手段。