散射系数矩阵的计算及其应用

利用Gabor Daubechies（G? D）小波束域波场分解和传播在空间和方向上的双重局域性，提出了基于G? D小波束域叠前深度偏移进行角度域成像和计算局部散射系数矩阵的方法. 以简单分层模型为例，对不同探测系统的局部散射系数矩阵分布特征进行分析. 分析结果表明，在一定的探测系统几何布局下，由本文方法得到的局部散射系数矩阵能够较真实地反映局部结构的散射(或反射)特性. 通过局部散射系数矩阵进一步外推具有不同速度反差的水平界面随角度变化的反射系数，并估计界面的空间位置和倾角等说明局部散射系数矩阵的潜在应用.     

Research on Algorithm M8 Applying to TIP Prediction of China's Strong Earthquake Cases in the Past Decades

This paper offers a positive research result of TIP before 16 strong earthquakes in North and Southwest China and their nearby areas since 1979 by using improved algorithm M8.The result showed that 14 of them were determined to occur within the times of increased probability.TIP precaution occupies about 37% of the total space-time domain.That means we have made quite good results of intermediate-term prediction of strong earthquakes.So the method could be used as one of the useful means of the intermediate-term prediction of strong earthquakes.     

沿地震带地震迁移的有序特征

对大华北的山西、燕山、华北平原和长江中下游地震带内的地震迁移规律、各带地震的迁移速度和地震序列特征进行研究,结果表明,各地震带是有机地联系在一起的,形成个统一体。     

中国北方寒武—奥陶系岩溶层组类型及其区域变化规律

本文在大量剖面资料统计的基础上,根据岩层的厚度比例和连续厚度及其组合形式,对我国北方寒武—奥陶系岩溶层组类型进行了划分,着重论述了岩溶层组类型的区域变化规律。为含水层系统的划分和水资源评价及区域岩溶发育规律的研究,提供了重要的基础资料。      

任重道远的地震预测研究

１９５６年,在全国１２年科学技术发展远景规划中,明确提出了地震预报的课题。１９５８年,当时中国科学院地球物理研究所以郭增建为首的的科研人员组成了“地震预报考查队”,赴甘肃和宁夏地区收集、了解１９２０年海原大地震大量的宏观前兆及地质条件等资料,奏响了我国现代地震预测研究的序曲。１９６６年３月８日,邢台发生６．８级强烈地震,这是新中国成立以后第一次造成人民生产财产巨大损失的破坏性地震。当天周恩来总理赶到邢台,并来到地震工作者中间,他说：“这次地震,代价极大,必须找出规律总结经验,希望你们这一代能解决…     

Comprehensive Approaches to Earthquake Prediction

There may be various anomalies from fields of multi-discipline before large earthquakes, including seismological anomalies and the anomalous changes in crustal deformation, underground fluids, geochemistry, geomagnetic fields, ground resistivity, etc. Precursors of a single discipline only reflect the process of earthquake preparation from one aspect. Only when various precursors from multi-disciplined fields are put into a unified process of earthquake preparation can the process be understood and identified comprehensively. The comprehensive methods used in earthquake prediction are outlined in this paper. The relationship that the forthcoming main shock bears with the precursory features such as the time-space distribution, the order of the precursors, etc. is analyzed. Research shows that a few of the main shocks can be predicted with the comprehensive methods to some extent.     

Empirical Approaches to Earthquake Prediction: A Brief Review of the Practice and Research in China

This paper gives a brief review of some progress in the research and practice of earthquake prediction in China in terms of the study of strong earthquake cases in three disciplines of precursory means: crust deformation and strain, underground fluid dynamics, and geoelectro-magnettsm, summarized in the past 30-odd years. All the progress, however, shows that the research of earthquake prediction in China is still in the empirical stage of its development. The main tasks in this stage would involve the following aspects: (1) accumulating earthquake cases, particularly the cases of strong earthquakes with a wide variety of reliable precursory data observed by fixed or mobile networks of different disciplines; and (2) studying the physical mechanism of observational means in more detail and the synthetic model of earthquake preparation based on the theoretical and laboratory researches as well as the data of in-situ observation.     

An Overview of Seismicity in China

This paper gives an overview of seismicity in China, including large-scale seismicity heterogeneity in space-time, aftershock activity, b-value, earthquake mechanism, and its possible mechanics.     

The Tectonic Feature of a Quasi-Trij unction in the Northeastern Corner of Qinghai-Xizang Plateau

Quasi-trijunction is a type of popular structure for certain scale tectonic blocks in a continent. There are two kinds of quasi-trijunction in the conjoining area formed due to rotation of continental blocks. They are the clockwise type and the anticlockwise type of quasi-trij unction. The shape of a quasi-trij unction may be gradually changed associated with block rotation and tectonic evolution, but, sediments and structure in the conjoining area can record the history of tectonic evolution. Thus, studying a quasi-trij unction can reveal regional tectonic evolution.Regional tectonic movement, plane strain partitioning and characteristics of seismic activity can be studied based on kinematics and geometric analysis of a quasi-trijunction.The quasi-trijunction is a surface structure controlled by deep crustal movement. Tectonic activity may be different in three branches. In the quasi-trijunction in the northeastern corner of Qinghai-Xizang Plateau, the NWW-trending Qilianshan-Hexi corridor fault zone w     

A Bayesian Approach to Seismic Hazard Estmation: Maximum Values of Magnitudes and Peak Ground Accelerations

Earthquake Researeh in Ch一na461 .METHODLet R be some value measured or estimated as a sequenee ina’‘Past”time interval(一丁,O)(I)万‘月,=(RI,…,R。),R,之R。,R=nlaX l二f匕11(RI,…,R,,) Values(l)eould have an arbitrary Physieal nature.BelowweshalleonsiderEq.(l)asearthquakemagnitudes in a given seismic aetive region or logarithms of seismie Peak ground aeeelerations at习given site.Ro isa而nimum eutoff value;it 15 defined by Possibilities of registration systems or wasehosen as the …