行星会合周期与强震的关系

行星运行都具有一定的周期性.近百年历次大震是在行星20,59,237年会合及合成与月回归下降时段内发震的.文内把近百年强震与当年天文年历及各大行星运行数据绘制地心距视赤经天象图,及5大行星黄经位置天象图,经过验证得出结论.供长期地震预报参考.     

1989年大同—阳高地震前山东地倾斜台网的短临异常特征

叙述了利用固体潮包络法和差分、日均值等方法识别大同—阳高6.1级地震前山东倾斜台网的前兆异常.认为泰安、马陵山自记水管仪和烟台石英摆倾斜仪3台仪器在时间、量级(10~(-7)弧度)和方向上具有一致性并分析了引起该情况的原因.     

石渠地震震害损失的评估及其背景条件

石渠5.1级地震的Ⅶ度(弱)区达160km~2,Ⅵ度区达2470km~2,震害损失值达4300余万元,在对其产生的背景条件和具体原因进行总结分析的同时并对存在的问题作了讨论。     

On the crust structure near focus and the far-field body wave synthetic seismograms

In this paper we discuss two types of crust models with abnormal density, velocity of wave and certain geometrical structures. The far-field synthetic seismograms of P and SH wave are calculated by the far-field vertical displacement formulas of P and SH waves with the double couple point source and the formulas of reflection coefficient, radiation pattern and travelling time difference derived from the models suggested in the paper. It is shown by the results that the effect of special crust structures near focus on the far-field seismograms can be ignored if the densities and wave velocity of the special structure are less than average those of the crust (model I). However the effect should be noticed if the densities and wave velosities of the structure are large than average those of the crust (modelI). The effect of the special crust structure on the far-field seismograms has not been studied further before. Seismic records of the Haicheng earthquake and the crust structure in Haicheng region are studied by the calculation method in the paper. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 1993.     

Rupture segmentation and assessment of probabilities of seismic potential on the Xiaojiang fault zone

Spatial distribution of sources of strong and large earthquakes on the Xiaojiang fault zone in eastern Yunnan is studied according to historical earthquake data. 7 segments of relatively independent sources or basic units of rupture along the fault zone have been identified preliminarily. On every segment, time intervals between main historical earthquakes are generally characterized by “time-predictable” recurrence behavior with indetermination. A statistic model for the time intervals between earthquakes of the fault zone has been preliminarily established. And a mathematical method has been introduced into this paper to reckon average recurrence interval between earthquakes under the condition of having known the size of the last event at a specific segment. Based on these, ranges of the average recurrence intervals given confidence have been estimated for events of various sizes on the fault zone. Further, the author puts forward a real-time probabilistic model that is suitable to analyze seismic potential for individual segments along a fault zone on which earthquake recurrence intervals have been characterized by quasi-time-predictable behavior, and applies this model to calculate conditional probabilities and probability gains of earthquake recurring on the individual segments of the Xiaojiang fault zone during the period from 1991 to 2005. As a consequence, it has shown that two parts of this fault zone, from south of Dongchuan to Songming and from Chengjiang to Huaning, have relatively high likelihoods for strong or large earthquake recurring in the future. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 322–330, 1993.