地震信息反馈系统的研制和应用

介绍了地震信息反馈系统的原理和功能,给出了系统的结构框图,对发送终端和接收终端的功能做了具体描述。在应用上也做了具体阐述,该系统能有效、快速地传送地震三要素信息。     

Analysis of the 1997 Zirkuh (Ghean-Birjand) aftershock sequence in east-central Iran

IntroductionThesouthernpartofKhorasanProvinceineast-centralIranisoneoftheseismicallyactiveregionsintheMiddleeast.Historicalreportsindicatedseveralearthquakeshavecausedseveredestructionsandhumanlossinthisregionduringthepastcenturies(Ambraseys,Melville,1982).Theinstrumentallyrecordedearthquakesaswellastheexistenceofseveralactivefaultsalsosug-gestedthattheregionhadahighpotentialofseismicactivities.OnMay10,1997at07:57:29.6GMT,12:27:29.6localtime,ashallowdestructiveearthquakewithoutanyfeltfores…     

华北中北部地区震源参数和场地响应的联合反演

利用遗传算法反演华北中北部地区27个地震震源谱的低频水平、拐角频率和25个台站的场地响应。具体方法是利用研究区的平均衰减模型对记录谱进行路径校正，然后假定每一个地震的ω^2模型，调整低频水平和拐角频率使所有台站场地响应的标准偏差最小，最后给出参与计算的每个台站的场地响应。结果表明，17个基岩台中11个台的场地响应在1～20Hz范围内接近1，6个基岩台的场地响应部分频段放大或缩小3倍以上。8个井下摆台站的场地响应形态相同，表现为低频放大，高频部分迅速衰减。地震矩与震级的关系为logM0=17．1 1．13ML，地震矩与震源半径的关系为logM0=19．4 0．0052r。     

铁路干线下的隧道施工关键技术

结合泰安抽水蓄能电站工程实例,介绍隧洞在穿越京沪铁路的施工过程中,采用震动监测技术优化爆破参数,顺利通过的施工技术。     

基于地震-测井数据预测储层参数空间分布规律的神经网络模型

研究了地震资料的特征参数与储层参数间的神经网络模型。建立了相互之间的非线性映射，可以横向预测目的层的储层参数，实现地震资料和测井资料联合预测储层参数的空间分布规律。实验结果表明，该方法是可行的。     

一种基于抗差自校正Kalman滤波的GPS导航算法

为减弱异常观测值对自校正Kalman滤波精度的影响,引入抗差M估计的等价权函数,建立了抗差自校正Kalman滤波算法,并用实例进行了验证。计算表明,该自适应滤波算法在完全未知噪声统计的情况下,不仅能够自适应地求解状态参数,而且还能在一定程度上有效地抵制观测异常对导航解的影响。     

Predicting ordinary kriging errors caused by surface roughness and dissectivity

The magnitude of kriging errors varies in accordance with the surface properties. The purpose of this paper is to determine the association of ordinary kriging (OK) estimated errors with the local variability of surface roughness, and to analyse the suitability of probabilistic models for predicting the magnitude of OK errors from surface parameters. This task includes determining the terrain parameters in order to explain the variation in the magnitude of OK errors. The results of this research indicate that the higher order regression models, with complex interaction terms, were able to explain 95 per cent of the variation in the OK error magnitude using the least number of predictors. In addition, the results underscore the importance of the role of the local diversity of relief properties in increasing or decreasing the magnitude of interpolation errors. The newly developed dissectivity parameters provide useful information for terrain analysis. Our study also provides constructive guides to understanding the local variation of interpolation errors and their dependence on surface dissectivity. Copyright © 2005 John Wiley & Sons, Ltd.     

Empirical models for estimating liquefaction-induced lateral spread displacement

Existing empirical models for estimating liquefaction-induced lateral spread displacement (D_LL) have been derived from a dataset poorly distributed with respect to earthquake magnitude and source distance, and also produced from different tectonic source types and faulting mechanisms. Both the poor distribution and mixed tectonic source types and faulting mechanisms of the data have an adverse impact on the reliability of the empirical models. To overcome these problems in the development of empirical models, we replace the direct use of magnitude and source distance with pseudo-displacement derived from spectral acceleration attenuation models that are well supported by earthquake data, and use a modification factor to account for effects of the non-linear soil response. Attenuation models derived from very large and reasonably well-balanced datasets have been selected, one being a Japanese attenuation model and other being a combination of the Sadigh et al. model and the Youngs et al. model. These models are capable of accounting for the effects of earthquake tectonic source type and faulting mechanism. We determined the model coefficients by selecting the pseudo-displacements calculated for a number of spectral periods to achieve an unbiased distribution of residuals with respect to earthquake magnitude and source distance. Sensitivity analyses have been carried out based on the new and existing models, and show that the new model is more robust than the existing models. Comparison with a limited number of data from the 1997 Kocaeli, Turkey earthquake suggests our model provides comparable liquefaction-induced lateral displacement D_LL estimates.     

Preliminary magnetic studies of lagoon and stream sediments from Chascomús Area (Argentina)—magnetic parameters as indicators of heavy metal pollution and some results of using an experimental method to separate magnetic phases

Magnetic properties of lagoon and stream sediments from Chascomús area (Buenos Aires Province) and the relevance of various magnetic parameters as giving pollution status are studied in the present work. This work is focussed on magnetic parameters, such as concentration-dependent (magnetic susceptibility, saturation anhysteric and isothermal remanent magnetisation) and feature-dependent parameters (S-ratio, coercivity of remanence, anhysteric susceptibility/magnetic susceptibility-ratio), as pollution indicators. Firstly and most importantly, different magnetic parameters and chemical measurements were correlated in order to investigate their goodness, obtaining the best results for feature-dependent magnetic parameters. Coercivity of remanence correlate very well with chemical variables, showing correlations at high level of significance up to 0.9094, and the anhysteric susceptibility/magnetic susceptibility-ratio also shows very good correlations (up to 0.8376). Some results and advantages of using a new experimental method in order to discriminate hard and soft magnetic phases are also shown. This method uses alternately backfield isothermal remanent magnetisation and alternating field demagnetisation. From the experimental separation, the presence of hard magnetic phases in some samples was confirmed.     

1999年9月21日台湾集集地震的震源参数综合判定

本文利用半经验、半理论的方法对世界各主要地震汇集和研究机构所给出的集集主震基本震源参数进行了综合计算和评定。根据这些参数重新计算了集集主震的标量地震矩、破裂面积、应力降等。根据这些参数之间的内在联系,从地震分类学的角度,判定集集地震是发生于板块边缘的大地震。可供研究台湾岛上地震活动性以及台湾地区板块构造演化问题参考。