Some Challenges of Short-Term Earthquake Forecasting and Possible Solutions

Doklady Earth Sciences - We discuss the reasons behind the lack of efficiency of geodetic monitoring aimed at short-term forecasting of strong earthquakes. Based on the results from geomechanical...     

强震前地磁秒数据异常及其短临预测意义

通过分析6个强震震中附近地磁Z分量秒数据的处理结果显示: 一些强震在震前反复出现较强的地磁异常现象.此现象在震前百余天至四十余天和临震前出现; 地磁场的特大异常持续天数随震级的增大而增大, 其异常天数与总体天数的比值随着震级的增大而增大.该特性对于短临地震预报预警及防震减灾具有一定意义.      

Prediction of the Deposition of Sulfate Salts Taking the Content of Strontium during the Exploitation of Oil Fields into Account

Based on the experience of developing an oil field on the Caspian Sea shelf, which was initially exploited with injection of seawater into the oil-bearing beds to maintain reservoir pressure, the deposition of sulfate salts under reservoir conditions is predicted. The prediction of sulfate deposition is made in two ways: analytical calculations according to the method of J.E. Oddo and M.B. Thomson and computer modeling. The prediction took the strontium content in the formation waters of the oil-field into account, which is usually ignored in production practice. It has been established that the prediction by computer modeling is more accurate; in particular, it considerably expands the temperature limits of anhydrite precipitation. The amount of potentially precipitable sulfate salts found by computer modeling has shown that the mass of deposited calcium and strontium sulfates is rather large, which can significantly reduce the permeability of the reservoir.     

Taking into Account the Influence of Relief in the Method of Microseismic Sounding

The traveling of surface waves in a model geophysical medium with a nonsmooth boundary is studied. It is shown that relief significantly distorts the microseismic noise field recorded at the day surface. This result should be taken into consideration when interpreting the data of passive surface-wave geophysical studies of deep crustal inhomogeneities.     

Mathematical Model for the Motion of Solutions Taking into Account the Osmotic Effect

Doklady Earth Sciences - The generalized equations of solution motion are given both in porous media and in cavities taking into account the osmotic effect. In certain cases, commonly small...     

地下水位对近震和远震异常响应的比较——以汶川地震和苏门答腊地震为例

地震引起的深层地下水位异常具有多样性和复杂性的特点。为了进一步探索深层地下水位动态与地震作用过程之间的联系机制,发挥深层地下水位对地震活动的指示作用,以2008年汶川Ms8.0地震和2007年苏门答腊Ms8.5地震为研究背景,对川、滇、陕、甘、渝地区井水位对两次地震的响应特征进行了比较。研究发现:地下水位远震响应形态主要以振荡型和阶变型为主,异常出现的时间较晚;地下水位近震响应形态比较复杂,以阶变型、脉冲型以及振荡型为主,异常出现的时间几乎与地震的发生同步。根据深层地下水位对地壳应力的响应机理,分析了各典型井水位对远震和近震不同响应的原因。结果表明:地下水位对远震的响应主要是由于含水层介质受到地震波应力的作用;对近震异常响应原因比较复杂,主要是含水层介质受到区域构造应力和地震波应力的共同作用的结果,震中距越小,含水层受到震源构造应力场的控制作用越大。     

Profile of the 9.85-GHz Neutral Hydrogen Line Taking into Account the Zeeman Effect (Computations and Solar Observations)

Astronomy Reports - The 9.85-GHz (3.04 cm) line of atomic hydrogen due to the 22P3/2–22S1/2 transition between levels of the hyperfine structure occupies a special place in the complex...     

应用于地震预测的遥感气体地球化学

利用卫星高光谱技术可以监测到大震前后地下气体释放引起的气体地球化学异常。利用AIRS标准产品数据中CO和O3月平均数据构建全球9年(2003—2011年)平均CO月背景场和O3月背景场,运用差值法(地震发生当年数据—背景场数据)开展震例研究。通过调研全球自2003年以来7级以上震例,系统地进行2003年以来全球7级以上地震的震例分析,对典型震例进行分析,总结CO和O3时空异常特征。     

Characteristics of Internal Gravity Waves and Earthquake Prediction

Doklady Earth Sciences - On the basis of the data on perturbations in the Earth’s atmosphere recorded before and after 52 significant earthquakes that occurred during the period from 1997 to...     

基于RBF神经网络的软基短期沉降预测研究

RBF(radial basis function)神经网络是一类比较优越的前向式多层神经网络,比传统的BP网络有较快的收敛速度.以深圳湾西部通道填海软基沉降的预测分析为例,探讨采用RBF神经网络解决这一问题的方法.采用插值方法构建时间间隔统一的时间序列数据并进行归一化处理,在此基础上建立了沉降变形时间序列的RBF神经网络模型,通过训练网络模型来预测沉降量.计算实例表明,模型具有运算速度快、预测精度高的特点,是一种具有应用前景的软基预测新方法.     

The Collimated Propagation Causes of Astrophysical and Laboratory Jets

Astronomy Reports - The use of Z-pinch facilities makes it possible to carry out well-controlled and diagnosable laboratory experiments to study laboratory jets with scaling parameters close to...     

声发射预报地震的岩体力学分析

岩体受压破坏是由于岩体内裂纹扩展及新的宏观裂纹产生不断积累的结果,大规模岩体受压破坏前会发生局部岩体的先前断裂破坏。裂纹起裂、快速扩展和止裂会产生声发射现象,局部岩体断裂破坏会产生强烈的声发射现象,通过对岩体声发射的监测分析可以预报受压岩体破坏的时间。因此,通过对地壳岩体声发射的监测分析,可以进行地震的短期和临震预报。通过对岩体受压应力分布规律的分析,得出通过监测地壳浅部地应力和地形变预报地震是没有实际意义的结论。     

强化公司财务管理——美国公司假帐的启示

2001年底以来美国《财富》500强排名第七位的安然公司，因5.52亿美元虚假利润丑闻和财务危机突然宣布破产，暴露了美国公司治理中存在的财务管理问题，使人们不得不对美国公司治理模式进行重新审视。在思考美国公司治理教训的同时，深入研究中国公司中的财务管理问题，对完善公司治理结构有重要的现实意义。     

试论天然半导体矿物的热电特性及其在地震预测中应用的可能性

本文基于半导体矿物热电特性的基本理论,通过大量科学研究成果之间客观联系的分析,论证了天然半导体矿物热电特性与地震预测的关系.结果表明,地壳内广泛存在天然半导体矿物,且绝大多数天然半导体矿物具有热电特性.孕震过程产生梯度热场时,会激发周围热电介质产生热电势,热电势的积累对孕震区电场具有一定的干扰效应,这种干扰效应可作为地震预测的信息源之一.另外,从成矿带和地震带之间的空间关系分析,可以认为天然半导体矿物的集中分布与地震活动带相一致.上述结论对深刻理解地震地电异常机理有重要的意义.     

Progress in the Application of Ground Gravity Observation Data in Earthquake Prediction

The mechanism of earthquake inoculation and the process of earthquake occurrence are very complicated. Additionally, earthquakes do not happen very often, and we lack enough cognition to the earth’s interior structure, activity regularity and other key elements. As a result, research progress about the theory of earthquake precursors has been greatly restricted. Ground gravity observation has become one of the main ways to study earthquake precursor information in many countries and regions. This paper briefly summarized the surface gravity observation technology and observation network in China: the surface gravity measurement instrument developed from Huygens physical pendulum in seventeenth Century to today’s high-precision absolute gravimeter, and its accuracy reached to ±1×10^-8 m/s². China has successively established the National Gravity Network, Digital Earthquake Observation Network of China,the Crustal Movement Observation Network of China Ⅰ and the Crustal Movement Observation Network of China, to provide a public platform for monitoring non tidal gravity change, seismic gravity and tectonic movement. The use of specific examples illustrated the role of gravity observation data in earthquake prediction. The gravity observation data of ground gravity can be used to capture the information of gravity change in the process of strong earthquake inoculation, and to provide an important basis for the long-term prediction of strong earthquakes. The temporal and spatial variation characteristics of the regional gravity field and its relation to strong earthquakes were analyzed: Before the earthquake whose magnitude is higher than M_S 5, generally there will be a large amplitude and range of gravity anomaly zones. Strong earthquakes occur mainly in areas where the gravity field changes violently. The dynamic change images of gravity field can clearly reflect the precursory information of large earthquakes during the inoculation and occurrence. Finally, the existing problems of surface gravity technology in earthquake precursor observation were put forward and the use of gravity measurement data in earthquake prediction research was prospected.     

勘探阶段矿井瓦斯涌出量预测方法探讨

矿井瓦斯是当前影响煤矿安全生产的主要灾害因素,如何在矿井设计、建设前,建立一个比较可靠的矿井瓦斯涌出量预测方法,较准确地预测矿井瓦斯涌出量是一项重要工作。基于分源预测法,结合多年工作实践,建立了勘查阶段结束时,从整个井田及井田历史角度出发的矿井瓦斯涌出预测方法。根据瓦斯地质来源将其划分为邻近层瓦斯涌出、采出煤瓦斯涌出、井下残留煤瓦斯涌出、围岩瓦斯涌出、井田周围煤层瓦斯涌出等5类瓦斯源,并分别建立了相对应的预测公式。通过实例应用,证明该方法有一定的可靠性。     

卫星热红外遥感在地震预测和断层活动中的应用研究进展

近年来,利用卫星技术通过测量地—气系统的红外辐射来探测地表的热状况,使热红外遥感在地震预测方面取得了显著成就。本文回顾了红外遥感资料应用于地震预测的研究成果,阐述了地震热红外短临预测方法的研究进展及应用实效,介绍了利用热红外遥感信息研究断层活动变化的探索与发展,探讨了地震热红外异常发生的机理,并就该技术的应用与理想效果之间的差距提出了未来工作的研究重点。