中国大陆原地复发强震的基本特征及其预测

在印度板块与欧亚块相碰撞形成的喜马拉雅弧板块边界力作用下，中国大陆有自己独特的现代构造运动和地震活动基本格架。格架是两组近似于对数螺线的现代构造滑移线，即最大剪切应力和剪切应变集中释放的区，带。在这种格架控制下，强震和大震在原地或基本在原地重复发生是中国大陆地震活动的重要特征。本文还提出了ｉ－ｆ－ｊ复发轮回模式和估计当前轮回强震复发时间的概率分布以及计算未来强震复发概率分式。为中，长期预测原地复发     

台湾费丛峡谷对强地面运动的影响研究──利用单台资料及2．5维SH混合方法

本文通过格林函数反褶积方法，由台湾峡谷附近的记录资料预测峡谷区的强地面运动的时程曲线．峡谷区的理论格林函数应用２．５维ＳＨ混合方法求解．通过格林函数反褶积方法得到的峡谷区费丛１及费丛２台的位移、速度、加速度和实际资料对比，取得了满意结果．计算结果表明，峡谷底部的峰值加速度相对峡谷边缘为最小；在靠近震中的一侧，峡谷的加速度的最大振幅相对比另一侧大．还给出了其余３个台的预测结果，研究了它们的加速度傅里叶谱和反应谱．     

动态聚类-模糊模式识别及其应用

本文以模糊子集论为指导,在迪戴的DCM法的基础上提出了动态聚类-模糊模式识别方法。实际上,它是一种新的模糊聚类的方法。该方法以DCM法的动态聚类部分做为原始数据变换的手段,而将迪戴的强模式概念推广为模糊模式,将强模式识别推广为模糊模式识别。此外,还提出了模糊模式间联系度的概念,从而解决了类间联系、类内典型个体、类间过渡个体、个体对各类的隶属程度以及内部有某种演化趋势的类别的划分等问题。文章还给出了该方法的数学模型和算法概要。最后,通过一个在地质学中的应用实例,说明了该方法的应用效果。     

消除强震加速度记录数字化误差的方法和处理软件

本文详细地分析了用数字化仪和激光扫描仪对模拟加速度记录进行数字化时所产生的误差及消除这些误差的方法，并开发了相关处理软件。数字化误差由数字化设备的系统误差和读数员在操作过程中的随机误差迭加而成，随机数字化误差是具有各态历经性质的、其振幅按高斯规律分布的平稳随机过程。利用激光扫描仪做强震记录数字化，工作效率很高。本文给出了激光扫描仪分析处理软件和消除数字化噪声实例。     

几种辅助设备在强震仪中的应用

本文介绍了GPS、eMODEM、DE-211串口设备服务器等辅助设备在GDQJ-2型固态地震动强度记录仪中的应用，包括各自的功能、作用、实现方法以及和强震仪的接口。     

云南地区断层形变群体异常与成组强震

运用前兆综合信息量S、前兆群体非均匀度ID以及近源异常凸现值NS的数学分析这三种方法，对云南地区1982～2004年跨断层短基线短水准资料进行了分析处理．结果表明，在云南地区Ms≥6强震前断层彤变群体异常显著，尤其是成组强震前，群体异常信息较为丰富。     

2004年12月26日印尼大地震河北省数字水位、地热记震能力分析

分析了我省地震监测井网数字化水位、地热资料对2004年12月26日印尼大地震的震后反映,分析了水位、地热对地震波反映的表现形态.通过分析可验证我省2001年新上数字资料-水位和地热的可靠性、灵敏性,以便科学地分析数字水位、地热资料、提取可靠的前兆异常信息,高效地服务于日常地震分析预报工作.     

东昆仑活动断裂带东段古地震活动特征

东昆仑活动断裂托索湖——玛曲以东肯定那一带， 可据阿尼玛卿玛积峰为界再分为花石峡段和玛沁段两个在几何上不连续的段落. 两段在表征断层全新世活动特征的古地震事件方面有明显差异， 花石峡段的地震活动性明显高于玛沁段的地震活动性. 古地震研究表明， 花石峡段上3次强震活动相邻两次地震发生的时间间隔分别约为500 a和640 a， 玛沁段上最近两次古地震事件间大致有1 000 a左右的时间间隔. 根据断层平均滑动速率计算的花石峡段7.5级地震的平均复发间隔为411~608 a， 相对应的同震平均水平位错约为（5.75plusmn;0.57）m. 虽然玛沁段的地震活动性较弱， 但由于该段上最近一次地震事件离现在较为久远， 已经积累的应变能应该使我们对其未来地震危险性的分析有足够重视.      

Simulations of strong ground motion in SW Iberia for the 1969 February 28 (Ms= 8.0) and the 1755 November 1 (M∼ 8.5) earthquakes – II. Strong ground motion simulations

This is the second paper of a series of two concerning strong ground motion in SW Iberia due to earthquakes originating from the adjacent Atlantic area. The aim of this paper is to use the velocity model that was proposed and validated in the companion paper for seismic intensity modelling of the 1969 ( M _s= 8.0) and 1755 ( M = 8.5–8.7) earthquakes.
First, we propose a regression to convert simulated values of Peak Ground Velocity (PGV) into Modified Mercalli Intensity (MMI) in SW Iberia, and using this regression, we build synthetic isoseismal maps for a large ( M _s= 8.0) earthquake that occurred in 1969. Based on information on the seismic source provided by various authors, we show that the velocity model effectively reproduces macroseismic observations in the whole region. We also confirm that seismic intensity distribution is very sensitive to a small number of source parameters: rupture directivity, fault strike and fault dimensions. Then, we extrapolate the method to the case of the great ( M = 8.5–8.7) 1755 earthquake, for a series of hypotheses recently proposed by three authors about the location of the epicentral region. The model involving a subduction-related rupture in the Gulf of Cádiz results in excessive ground motion in northern Morocco, suggesting that the source of the 1755 earthquake should be located further west. A rupture along the western coast of Portugal, compatible with an activation of the passive western Iberian margin, would imply a relatively low average slip, which, alone, would could not account for the large tsunami observed in the whole northern Atlantic ocean. A seismic source located below the Gorringe Bank seems the most likely since it is more efficient in reproducing the distribution of high intensities in SW Iberia due to the 1755 earthquake.     

Spatial variability and non-linearity of strong ground motion near a fault

We present observations of ground accelerations recorded at a small array close to the fault during the Düzce earthquake and its early aftershocks. The records show the strong spatial variability of ground acceleration over distances of only a few hundred metres. During the main shock, the peak horizontal acceleration values ranged from 0.3 to about 1.0 g at stations distant of 1.5 km only. We attribute this spatial variability to a fault zone site effect as peak ground acceleration steadily increases as the distance to the fault trace decreases. The spectral ratio between the ground motion recorded near the fault and the one outside the fault zone shows a shift of the spectral peak to lower frequencies with increasing peak accelerations. Such an observation suggests a non-linear behaviour of the fault zone due to the strong ground shaking. As much as a 45 per cent reduction in the shear wave velocity is necessary for the observed shifts. The opening of pre-existing cracks throughout the fault zone is the proposed mechanism to account for the observed shear wave reductions. The observation that elastic fault zone properties are soon recovered following episodes of large strains shows that cracks and fissures close rapidly after the strong shaking is over.