构造地球物理学在孕震环境研究中的应用及其相关问题

简要论述了用构造地球物理学研究地震构造环境的基本思路、方法程序等,并从中长期地震预报及工程地震角度对这门交叉学科的产生背景、完善发展、科学意义与前景等相关问题进行了讨论.     

基于CAC的一类通用多焦点地图投影

本文从新的角度提出了一类在计算机辅助制图情况下具有灵活、通用性的多焦点地图投影方法。介绍了这种方法的原理、给出了若干可满足用户复杂需求的投影公式及其相应的算例。利用本文提出的方法,不仅能够概括或产生大部分现有的变比例尺、多焦点地图投影,而且可以获得更为广泛的结果。     

新疆乌苏一呼图壁县一带活断层及古地震

在解译法国斯波特(SPOT)卫星影象基础上,实地勘查了独山子背斜北翼地区,确定出7条活断层。古地震和活断层的研究表明,北天山西部山前一带为潜在震源区。     

Preliminary study of the straticulate structure of crust-mantle beneath east Guangdong and south Fujian Provinces of China

Using the 12 deep focus teleseismic P waveforms recorded by 6 short-period seismographs in east Guangdong and Fujian region of China as the observed data, synthetic P waveforms comparable to the observed ones are obtained by gradually adjusting the crust-mantle model and calculating the corresponding synthetic seismograms. The results suggest that the crust-mantle structure in this region is a vertically straticulate media structure consisting of 3 pairs of thin layers with a high- and low-velocity alternation. The crustal thickness tends to increase gradually from south to north, being 31.5 km in the south and 32.4 km in the north. Finally, the suggested model is tested using the explosive data of Yunfu, Guangdong Province. The theoretical travel-time of P waves agrees fairly well with the observed travel-time. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,14, 172–179, 1992.     

中国东北深震及其构造意义

概述了中国东北深震的时空分布、主应力优势方向以及深震区内的火山活动等特征。依据日本海沟到中国东北东部地震空间分布、震源机制解、俯冲板块的温度结构以及东北深震与海沟浅震的关联等大量资料，论述了中国东北深震是西太平洋板块高速度、小倾角向欧亚大陆下俯冲的结果。讨论了中国东北深震的板块构造意义。     

State of stress in the Southern Tyrrhenian subduction zone from fault-plane solutions

In this paper we present revised locations and original focal mechanisms computed for intermediate and deep earthquakes that occurred within the Southern Tyrrhenian subduction zone between 1988 and 1994, in order to improve our knowledge of the state of stress for this compressional margin. In particular, we define the stress distribution within a large portion of the descending slab, between 40 and about 450 km depth. The seismicity distribution reveals a continuous 40–50 km thick slab that abruptly increases its dip from subhorizontal in the Ionian Sea to a constant 70° dip in the Tyrrhenian. We computed focal mechanisms for events with magnitudes ranging from 2.7 and 5.7, obtaining the distribution of P - and T -axes for many events for which centroid moment tensor (CMT) solutions are not available, thus enabling the sampling of a larger depth range compared to previous studies. We define three portions of the slab characterized by different distributions of P - and T -axes. A general down-dip compression is found between 165 and 370 km depth, whereas in the upper part of the slab (40–165 km depth) the fault-plane solutions are strongly heterogeneous. Below 370 km the P -axes of the few deep events located further to the north have a shallower dip and are not aligned with the 70° dipping slab, possibly suggesting that they belong to a separated piece of subducted lithosphere. There is a good correspondence between the depth range in which the P -axes plunge closer to the slab dip (∼ 70°) and the interval characterized by the highest seismic energy release (190–370 km).     

八达岭及周缘地区壳幔结构与潜在震源探讨

利用Ｓｅｉｓ８３程序包，对盐山大兴延庆剖面的大兴延庆段人工地震测深资料进行了计算处理，获得了八达岭及周缘地区地壳上地幔结构．结果显示，该区浅部断裂发育，沉积层厚度差别大；其深部构造在横向上存在着明显的不均匀性，速度等值线起伏变化明显，局部存在低速块体．莫霍面由剖面东段的大兴向延庆方向倾斜，大兴附近莫霍面的深度为３４．５ｋｍ，居庸关附近为３８．５ｋｍ．在延庆附近莫霍面存在一断裂     

1997年10—12月的全球地震动态

１９９７年第四季度,全球地震活动为高水平。６级以上地震频度不高,但两次７级以上地震面波震级偏高。中国西藏地区发生玛尼７．４级地震。地中海地区中强地震活跃。全球发生较大的深源及中深源地震７次。     

经验格林函数法和遗传算法在震源谱研究中的应用

发展了传统的经验格林函数方法，将其与遗传算法结合起来用于地震震源谱的研究，以求得较大地震震源谱的高频衰减趋势的斜率。在此基础上先用遗传算法较为精确地搜索出较大地震的拐角频率，再用遗传算法对较大地震的振幅谱因衰减造成的损耗进行补偿，从而确定自震源至地震台传播途径上的介质品质因子Q值，最后给出了利用乌鲁木齐区域遥测数字地震台网资料测定Q值的范例。从计算结果得出乌鲁木齐至北天山一带的乌苏地区地震震源谱的高频衰减趋势满足ω^-2形式，Q值在480左右。     

高精度钻孔超声波成像原理及解释技术

介绍了钻孔超声波成像的工作原理。由于该系统具有图像分辨率高、方位确定准确的特点,特别适合于确定岩石节理(或岩层)的走向、倾向、倾角,裂隙和破碎发育情况。可根据工程的需要,提供多种综合分析图件,为大型工程的地基基础的地质结构分析、评价提供可靠依据,在香港开展的工程中使用了钻孔超声波成像,取得较好效果。