Emergency Seismic Damage Assessment of the M_S8.0 Great Wenchuan Earthquake Based on Remote Sensing Imagery

The fast processing, seismic damage data extraction and loss evaluation from RS imagery acquired immediately after a destructive earthquake occurs, are important means for compen-sating the insufficiency of seismic damage information from ground-based investigations and provide an important basis for emergency command and rescue. The paper introduces the method of emergency seismic damage assessment using remote sensing data and its application to the great Wenchuan earthquake of magnitude 8.0 occurring in southwest Sichuan Province on May 12, 2008. The practical effectiveness of the method is also evaluated in the paper.     

2008年3月30日肃南Ms5．0地震前兆异常特征研究

对张掖中心地震台近期的前兆资料进行全面论证,并结合祁连山地震带地震活动性特征,对2008年3月30日肃南5.0级地震前兆异常特征进行研究.结果认为:此次地震的发生基本符合祁连山地震带地震活动的周期性特征,部分前兆资料有明显的短临异常显示.     

The relationship between the growth process of the ferromanganese crusts in the pacific seamount and Cenozoic ocean evolvement

Base on the Os isotope stratigraphy together with the empirical growth rate models using Co concentrations, the growth ages of the ferromanganese crusts MHD79 and MP3D10 distributed in the seamount of Pacific are confirmed. Through the contrast and research on the previous achievements including ODP Leg 144 and the crusts CD29-2, N5E-06 and N1–15 of the seamount of the Central Pacific, the uniform five growth and growth hiatus periods of them are found, and closely related to the Cenozoic ocean evolvement process. In the Paleocene Carbon Isotope Maximum (PCIM), the rise of the global ocean productivity promoted the growth of the seamount crust; the first growth hiatus (I) of the ferromanganese crust finished. In the Paleocene-Eocene Thermal Maximum (PETM), though the vertical exchange of seawater was weakened, the strong terrestrial chemical weathering led to the input of a great amount of the terrigenous nutrients, which made the bioproductivity rise, so there were no crust hiatuses. During 52–50 Ma, the Early Eocene Optimum Climate (EECO), the two poles were warm, the latitudinal temperature gradient was small, the wind-driven sea circulation and upwelling activity were weak, the terrestrial weathering was also weakened, the open ocean bioproductivity decreased, and the ferromanganese crust had growth hiatus again (II). From early Middle Eocene-Late Eocene, Oligocene, it was a long-term gradually cooling process, the strengthening of the sea circulation and upwelling led to a rise of bioproductivity, and increase of the content of the hydrogenous element Fe, Mn and Co and the biogenous element Cu, Zn, so that was the most favorable stage for the growth of ferromanganese crust (growth periods III and IV) in the studied area. The hiatus III corresponded with the Eocene- Oligocene boundary, is inferred to relate with the global climate transformation, celestial body impact event in the Eocene-Oligocene transition. From the early to the middle Miocene, a large-scale growth hiatus (hiatus period IV) of the ferromanganese crust in the studied area is inferred to relate with temporary warm up climate and ephemeral withdrawal of Antarctic bottom water in the early Miocene. After that, the Antarctic ice sheets extended, the bottom water circumfluence strengthened, the ocean fertility increased, and the once interrupted crust continued to grow in the late Miocene (growth period V). Supported by China Ocean Mineral Resources Research and Development Association “10th Five Year” Topic (Grant No. DY105-01-04-14)     

海南省“十五”测震台网运行后台站的维护

海南省“十五”测震台网是集数字化、综合化、自动化技术为一体的大动态、宽频带地震观测系统,在地震速报、预报和地震科学研究中发挥重要的作用。本文通过对海南省测震台站故障情况的分析和总结,介绍地震台站维护的一些经验和方法。     

黑龙江省德都地震发生前后依安102井水位异常及其分析

概述了依安102井水位、声响的映震异常特点,指出了异常水位、异常声响,并非人为因素造成,不受大气降水过程的干扰影响,提出了孕发地震的区域应力—应变异常场同映震水位、映震声响之间,存在着内在的密切联系,结论认为,依安102井的水位异常、声响异常,同孕发德都地震的应力—应变区域异常相呼应,依安102井所在地处于德都地震孕震应力场直接影响范围。     

Comparative experimental studies of models of self-controlled and ordinary frames on the shaking table

This paper presents a comparative test of models of self-controlled and ordinary frames on the shaking table. Two tested 1/8-scale models of 4-storey and single-bay RC frames made of cement mortar and reinforced with wires were poured on the same base beam. The dynamic characteristics and earthquake responses in the elastic, cracked and failed stages and the failure modes of these two kinds of frame are studied. It is proved that the seismic behaviour of the self-controlled frame is better than that of the ordinary frame.     

锈蚀钢筋混凝土框架中节点抗剪强度研究

随着服役时间的增长，侵蚀环境下钢筋混凝土框架节点因钢筋发生不同程度的锈蚀而造成承载性能下降，严重影响建筑结构的安全使用。本文在已有钢筋混凝土框架节点抗剪强度理论模型的基础上，考虑钢筋锈蚀对框架节点受力性能的影响，建立锈蚀钢筋混凝土框架中节点受剪承载力计算公式。通过11组锈蚀钢筋混凝土节点试验数据，对建议理论模型进行验证。研究结果表明，锈蚀钢筋混凝土节点受剪承载力试验值与理论计算值之比的平均值为0.951，方差为0.075，二者吻合较好，本文建议的计算方法可用于锈蚀钢筋混凝土框架中节点承载力分析。     

土层地震反应传递函数的模拟

探讨了用单一土层模型替换复杂场地求解土层场地传递函数的方法,并用ＳＭＡＲＴ－１台阵地震记录对这一方法的可行性进行了研究和讨论,结果表明,只要选取适当的地震波入射角Ψ和土介质的滞回阻尼比ｄ,简化模型的传递函数与实际传递函数能符合得较好,这一方法可用来近似估计缺少详细土质勘测资料地区的土层地震反应的传递函数。     

石咀山市地貌与反应谱间的关系

本文在实地调查的基础上,将宁夏石咀山市按地貌单元分为三个区。对每个地貌单元场地土的动力特性进行了试验研究。根据一维地震反应计算模型,计算求得了各个地貌单元的平均反应谱,讨论了不同类型的地貌单元与其对应的反应谱之间的关系,最后给出了相应的设计反应谱。     

2020年7月12日河北省唐山市古冶区MS5.1地震数值预测

1 研究背景地震预报中测震学指标广泛应用于地震异常分析.顾瑾平等(2001)研究了多项指标综合预测概率,得出综合概率值在0.5以上时,对应地震率80％,测震学指标有其物理意义,若出现高综合概率值时应关注.2020年7月12日,在河北省唐山市古冶区发生MS 5.1后期强余震(39.78°N,118.44°E),震中位于...