地壳形变前兆及其应变量转换

归纳了自1975年以后华北地区13次中强以上地震的地壳形变短临前兆异常60例。统计地壳形变短临异常与地震的定性关系，发现距震中较远的台站异常出现较早，较近的台站异常出现较晚，地震的震级与异常的空间展布范围成正比，异常往往倾向震中或背向震中。跨断层的位移型形变异常形态有两大类：一类是趋势性异常变化，另一类是高频波动。本文提出了将连续型形变转化为应变的方法。从1989年10月16日大同－阳高61级地　震和1991年3月26日大同－阳高5．8缓地震的实例可见，地震往往发生在高应变区或其附　近，异常量级可达10－6。     

华南西部地区近期中强地震前定点形变异常特征分析

通过研究华南西部地区近期发生的5级以上地震,梳理中强地震前定点形变观测资料出现的异常特征,分析形变曲线异常变化特征与华南西部地区中强地震的关系。结果表明：趋势变化异常对华南西部地区5级以上地震的发生有一定的指示意义,当区域内出现与自然环境和观测环境无关的趋势变化异常超过3个月,异常台站300 km范围内存在发生5级左右地震的可能。研究得到的认识对华南西部地区地震前兆异常识别以及地震趋势研究有积极的意义。     

中国第二代地形变连续观测台网

本文回顾了我国地形变连续观测台网的发展,总结了为建立能清晰正确记录固体潮汐的第二代台网所作的努力。 近两年内几次中强地震前震中附近台站所测到的形变异常,证实了建立第二代台网的成效。     

乌鲁木齐形变站水准异常变化特征与地震关系的研究

通过对发生在2003年9月27日俄、中、蒙交界Ms≥7.9级和2007年7月20日特克斯Ms≥5.9级地震前后,乌鲁木齐形变台站垂直形变资料异常特征的分析和研究认为,乌鲁木齐形变台站的前兆观测资料具有较好的映震能力,对乌鲁木齐周边及北天山中西部地区5～6级以上地震有较好的震前反应,前兆信息明显。地震前后形变形态表现为低...     

基于SBAS-InSAR的怀来地震台形变仪器干扰源区域分析

正在目前形变前兆仪器异常核实工作过程中,工作人员需要从仪器的工作状态、异常前后时间段内是否发生人为干扰、气象因素和台站周边观测环境干扰等方面进行现场异常核实。台站山洞周边区域土质为非均质,该区域范围内的地表形变会引起台站所在的基岩区发生倾斜,进而可能导致洞室内的水管倾斜仪和水平摆倾斜仪产生与地震前兆异常相关的数据异常变化。由于台站周边区域发生形变范围较大,且形变区域的形变量较小,因此,仅仅依靠人力对形变区     

中强地震前菏泽、郯城地震地电阻率各向异性值变化特征

对山东菏泽和郯城两台站地震地电阻率观测资料进行处理的基础上,研究了地震地电阻率各向异性的前兆异常特征,得出两台站周围300 km内的5级以上地震发生前均存在明显的地震地电阻率各向异性前兆异常,在中强地震发生时其各向异性值基本处于高值附近。对其物理机理进行了初步的探讨。     

承德地区形变资料前兆异常特征及映震能力分析

主要通过Nakai拟合、振幅因子以及非潮汐拟合常数3种方法对承德地区各个台站的各形变手段所得数据拟合处理,进行前兆异常分析,同时与该地区异常有效评价范围内的地震联系在一起,分析地震前兆异常与地震之间的关系.通过分台站、分手段、分拟合方法对各形变仪器映震能力进行R值评价,指出了形变异常观测在地震监测预报应用过程中存在的优...     

地震前地壳形变异常分布的非均匀性特征

利用Ｆ综合检验的理论,讨论了形变异常的定量化及检测准则。利用潮汐观测中的非潮汐形变讨论了大同和丽江地震前形变异常分布的非均匀性,并与地震活动的特征进行了对比。结果表明,震前１．５年左右,能检测出区域性的准同步形变异常,出现的异常空区可能是未来的地震危险区,且形变异常空区在震前应有强化或补偿现象。因而,在地震危险区的判定中首先面临的问题是地震孕育所处阶段的判定;在无法判别地震孕育阶段的情况下,形变异常台站周围和异常强度场中所出现的形变异常空区都是危险的。     

宁蒗5.7级地震前数字化形变观测短临异常识别与分析方法研究

由于采样率的大幅度提高,从数字化形变资料中能挖掘大量短临前兆异常信息,如地震前短周期的脉动、突跳、转折等。本文以2012年6月24日宁蒗5.7级地震为例,通过研究丽江、云龙台站数字化形变观测资料,对宁蒗5.7级地震前的形变短临前兆识别与分析进行了研究,给出了形变前兆异常识别方法。     

7．9级地震前乌鲁木齐形变站垂直形变异常特征初析

通过对2003年9月27日发生在新疆友谊峰东北7．9级地震震前乌鲁木齐形变站垂直形变异常特征的分析,得出该台站垂直形变在地震临震前有明显的异常反映,地震前北天山中、西段地区4．9级以上地震活动较活跃,垂直形变运动速率加速上升,地震当日观测数据出现突跳现象。     

A Monte Carlo study of rainfall forecasting with a stochastic model

A procedure for short-term rainfall forecasting in real-time is developed and a study of the role of sampling on forecast ability is conducted. Ground level rainfall fields are forecasted using a stochastic space-time rainfall model in state-space form. Updating of the rainfall field in real-time is accomplished using a distributed parameter Kalman filter to optimally combine measurement information and forecast model estimates. The influence of sampling density on forecast accuracy is evaluated using a series of a simulated rainfall events generated with the same stochastic rainfall model. Sampling was conducted at five different network spatial densities. The results quantify the influence of sampling network density on real-time rainfall field forecasting. Statistical analyses of the rainfall field residuals illustrate improvement in one hour lead time forecasts at higher measurement densities.     

Earthquake Engineering and Engineering Vibration Aims And Scope

正This journal is established by the Institute of Engineering Mechanics(IEM),China Earthquake Administration,to promote scientific exchange between Chinese and foreign scientists and engineers so as to improve the theory and practice of earthquake hazards mitigation,preparedness,and recovery.To accomplish this purpose,the journal aims to attract a balanced number of papers between Chinese and     

Foreword

Destructive earthquakes have caused great damage in China and the United States and collapsing buildings havecaused many deaths and injuries. The field of earthquake engineering studies earthquake hazards, the occurrence ofearthquakes of various magnitudes, the nature of the ground shaking during an earthquake, the vibration of structuresduring earthquakes, the strengthening of existing structures and the design of new structures to be earthquake resistant,and finally, how to cope with earthquake damage and restore a city to normal functioning. Such efforts are in progressin both countries, but unfortunately, the language barrier interferes with the free flow of information between China andthe Untied States. It would be mutually beneficial if some means could be developed to promote the exchangeof information across the Pacific Ocean. This new journal has been established for this purpose and its success willbe an important step in promoting earthquake engineering in China and the United States.     

WORLD ASSOCIATION FOR SEDIMENTATION AND EROSION RESEARCH(WASER)

正President:Giampaolo Di Silvio,Italy Vice Presidents:Ulrich C.E.Zanke,Germany Zhao-yin Wang,China The World Association for Sedimentation and Erosion Research(WASER),inaugurated on Oct.19,2004,is an independent non-governmental,non-profit organization.The mission of WASER is to promote international co-operation on the study     

Enhancing remote sensing research on global change to improve our understanding on Earth system processes

正Global Change includes climate change and other environmental changes caused by the joint interaction among various layers of Earth. From the positive side, global change provides new opportunities to human and other living forms on Earth. In the meantime, it creates tremendous challenges and negative impact. At present, the negative impacts have reached all primary processes of the global ecosystem and every aspect of human society, especially causing degradation of the ecosystem. For instance, intensive deforestation causes decline of biodiversity; global warming causes sea level rise and increases     

SCIENCE CHINA Earth Sciences SUBJECT INDEX TO VOLUME 57(2014)

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