DEEP TECTONIC STRESS CHANGE BASED ON LONG-TERM APPARENT RESISTIVITY TIME SERIES: A CASE STUDY FROM NORTH SECTION OF YISHU FAULT ZONE

Almost all the destructive earthquakes, so called tectonic earthquake, are produced by tectonic movement. The tectonic movement will cause resistivity changes in the earth. It's valuable for strong earthquake forecast to study the relationship between the resistivity change and tectonic movement. According to magnetotelluric sounding method, we establish a robust estimate method to calculate the long-term apparent resistivity from seismic station monitoring data. We first use 1D layered earth models to test the sensitivity of this method. Then we process the continually observed long term electromagnetic data in 4 years (from 2011 to 2014) from Anqiu seismic station which is very close to the north section of Yishu fault zone. The apparent resistivity curves and the apparent resistivity time series for different frequencies are obtained. The time series show the resistivity increase in the selected 4 years, which is in good agreement with the GPS baseline data. This also satisfies the results from rock mechanics experiments on deep rocks (upper mantle) that the resistivity will increase with improved stress in a high temperature and pressure environment. The method is valuable for studying electromagnetic precursor of strong earthquakes and strong earthquake prediction.     

Some important scientific problems in current lithospheric physics research in China

China has achieved much during recent years in the area of lithospheric physics research and promoted the development of the geosciences （Teng, 2004）. However, in the 21^st century, national needs and policy challenges the science of lithospheric physics. I suggest a general analysis, research, and development direction for lithospheric physics and point out clearly the content, core problems, and key scientific problems in this field. The realization of the earth and the discovery of the basic mechanisms of mountains, basins, minerals, and natural disasters depend basically on high-resolution observations of geophysics, the delineation of the fine structure of crust and mantle （2D and 3D） inside the lithosphere, substance and energy exchanges in the deep earth, the process of deep physical, mechanical, and chemical actions, and deep dynamical response. Therefore, geophysics should be the pioneer in the geosciences field in the first half of the 21^st century. I end with an analysis and discussion of some problems and difficulties in the research of lithospheric physics.     

基于多尺度卷积神经网络的结构损伤识别研究

为了利用结构振动响应的时间多尺度特征来提升卷积神经网络识别结构损伤的能力,给出了两种用于结构损伤识别的多尺度卷积神经网络,即多尺度输入和多尺度卷积核卷积神经网络.对于多尺度输入卷积神经网络,将通过下采样和滑动平均获取的具有不同时间尺度特征的振动信号输入固定尺寸卷积核的分支卷积神经网络;对于多尺度卷积核卷积神经网络,则将...     

Generalization of PhaseNet in Shandong and its application to the Changqing M4.1 earthquake sequence

Waveforms of seismic events, extracted from January 2019 to December 2021 were used to construct a test dataset to investigate the generalizability of PhaseNet in the Shandong region. The results show that errors in the picking of seismic phases(P-and S-waves) had a broadly normal distribution, mainly concentrated in the ranges of-0.4–0.3 s and-0.4–0.8 s, respectively. These results were compared with those published in the original PhaseNet article and were found to be approximately 0.2–0.4 s l...     

南黄海南部与东海北部之间的深部构造

针对南黄海南部与东海之间的深部构造，根据前一段地球物理研究的结果，与有关文献进行对比探讨，发现其差异．在重力和三维地震层析成像结果基础上，探讨分析了该海域的深部构造，给出分布在南黄海南部与东海北部之间的苏浙-济州岛构造带的分布位置、形态特征，并讨论了该构造带的性质、与周边构造体系和构造演化的关系．并指出这一构造由于朝鲜半岛西缘断裂带的存在而并未延伸进入朝鲜半岛．     

二维小波变换在地震勘探面波消除中的应用

在深层油气勘探中，针对深层地震数据的特点，我们利用二维小波变换技术易于分离信号和噪声的特点，将其应用于东部深层地震资料的处理中，对面波的消除取得了令人满意的结果，大大提高了深层地震资料的信噪比。     

浙江岛屿深井地震台防雷接地系统设计

针对当前岛屿深井地震台设备容易遭雷击及维修不便等问题,通过对雷电入侵台站设备的途径分析,依据现有防雷技术规范和相关理论,对观测房和井口防雷接地采用法拉第笼结构预防雷击,加强接地等电位连接,规范各种线路布设,综合多级雷电防护措施,使岛屿深井地震台站稳定可靠运行。     

康定榆林宫水热区CO_2研究

本文探讨康定榆林宫水热区水热ＣＯ２气的来源、区内主要水热点的ＣＯ２气释放强度及释放模式。稳定同位素分析结果表明,该水热区水热ＣＯ２气为深部成因,且有６０％以上为变质成因;估算得区内主要水热点的ＣＯ２气释放强度为１０８ｇ／ａ。结合研究区地质条件做出了水热ＣＯ２气释放模式示意图。     

锡矿山锑矿田幔-壳构造成矿模型及找矿预测

介绍湖南锑的区域地球化学背景特征,分析锑异常分布规律及与构造、岩浆岩的关系,探讨地壳演化与锑矿成矿作用,建立锡矿山锑矿田幔-壳构造模型,并进行找矿预测.     

深井复合钻柱技术在特深科学钻探中的应用探讨

深井复合钻柱技术是解决特深科学钻探超长钻杆柱可靠性问题的重要途径,其与设备能力、材料性能、钻进条件及管柱力学等息息相关。本文系统总结了复合钻柱技术在我国深部钻探中的发展和应用情况,在复合钻柱强度理论的基础上,探讨了不同复合钻柱的组合方案及其极限下深。研究结果表明,若以?216 mm直径终孔,仅依靠钢质钻柱已无法满足特深钻探13000 m的下深要求,而采用V150钢级?127 mm钻杆配合?127 mm钛合金钻杆及S135钢级?127 mm钻杆配合?129 mm铝合金钻杆可分别满足最大13484 m和18783 m的下深要求,钻柱总重分别仅有360.5 t和324.3 t,均具备可靠的安全性保障。本文对特深科学钻探用复合钻柱的设计和选择具有参考意义。