新疆新源、和静交界M_S6.6地震强震动观测记录初步分析

2012年6月30日新疆伊犁州新源县、巴州和静县交界发生MS6.6地震,新疆区域强震动台网有近40个强震动台记录到本次地震产生的地面运动,记录的最大峰值加速度为3.484 m/s2。文中初步收集了本次地震获取加速度记录,简要进行了分析,并完成了部分典型记录的特征计算,为新疆强震动研究提供参考依据。     

军队参与国际重大自然灾害救援行动工作机制建设的思考

向遭受严重自然灾害的国家或地区提供人道主义紧急支援,是各国军队在和平时期的重要使命。目前中国军队还没有成建制地出国参加过重大自然灾害的国际救援。本文介绍了联合国重大自然灾害国际救援行动协调工作机制、联合国框架下的军队资源参与灾害救援的工作机制。结合印尼地震海啸、海地地震等灾害中各国军队救援的情况,对我国军队将来参与国际重大自然灾害救援,在法律、预案和工作机制准备方面进行了分析,并提出了建议。     

多极距地电阻率观测系统的分布式电极控制器研制

详述数字电极的系统构成、电路结构、通信协议和其他关键技术。该系统的通信网络结构基于RS-485现场总线,通过环境测试和台站试验,发现数字电极技术适用于多极距电阻率系统。     

南海西北次海盆的磁条带重追踪及洋中脊分段性

由于缺少有效钻孔资料,对于南海扩张的时间一直存在较大的疑问.在南海三大海盆中,西北次海盆面积最小、磁条带特征不明显,因此对其扩张年代的争议最大.最新采集的高密度(小于10 km测线间距)船测地磁资料清晰地显示了西北次海盆磁条带的存在.在OBS和多道地震资料的约束下,利用船测地磁资料,本文对西北次海盆的地壳年龄进行了重追踪.根据定量的比较,西北次海盆的主体扩张始于35.8 Ma(C16n,2n),在34.7 Ma(C15)时其西南部开始扩张,扩张最终同时终止于33.2 Ma(C13n),整体的全扩张速率在40~50 mm/a之间.这表明南海的扩张可能首先起源于西北次海盆,在其结束扩张后,东部次海盆才开始打开(约30 Ma).得益于数据精度和密度的提高,利用化极后的磁力异常以及反演的磁化强度可以对西北次海盆进行二级中脊段的划分.我们共划分出六个中脊段和一个明确的转换断层.中脊的分段性与OBS反演的地壳厚度的变化相一致.转换断层东侧,中脊主体分为四个中脊段,每个中脊段长度均在30 km左右.转换断层西侧,存在一个长约50 km的中脊段和一个不确切的中脊段.中脊段上磁化强度的变化幅值和中脊段长度在整体上成正比.每个中脊段中央的磁化强度弱于中脊段两端的磁化强度,这与扩张速率相近的大西洋中脊的磁化强度特征一致.     

汶川8．0级地震与日本9．0级地震的同震响应特征——庐江地震台动水位与水温

自2000年庐江地震台数字化水位、水温观测以来,在多次大地震中水位、水温均有明显的同震效应,四川汶川8．0级地震、日本本州9．0级地震引起汤池1号井水位、水温的同震特征。动水位同震效应表现为脉冲变化,震后水位逐渐升高;水温表现为阶跃下降,震后水温缓慢恢复到正常状态。     

Finite element analysis of steep excavation slope failure by CFS theory

The distribution of Coulomb failure stress (CFS) change in the steep excavation slope is calculated by finite element method in this paper, and the failure mechanics under different conditions have been investigated. Comparing the CFSs before and after the slope excavation (stress loading and unloading processes), the dangerous internal zone and the most likely failure external area are attained. Given the shear cracks on the top surface while tensile stress or cracks along the toe of the slope, we analyze the high cutting-angle steep slope in Kaixian county of the Three Gorges Reservoir region. We bring forward that the peak value of CFS after excavation can reach to the order of 0.1 MPa, which is greatly higher than that of before. Our preliminary results are useful for optimizing the reinforcement structure during the steep slope stabilization engineering.     

基于人机工程学原则的地震公共标志有效性评估与建议

基于标志的人机工程学原则,对GB/T24362—2009中地震公共信息图形标志的有效性进行测试评估,结合理解率、熟悉度、物理相符性、概念相符性的测试数据,评估本标准中的标志符号是否符合国际标准化组织(ISO)评估标准,重点分析该标准中高理解率标志和低理解率标志的影响因素,探讨物理相符性、概念相符性和熟悉度影响标志理解率(P＜0.001)的机制机理。通过对测试数据的研究发现,物理相符性和熟悉度是影响标志理解率的最大因素,进而得出提升标志的有效性首先要提高标志图形的物理相符性、概念相符性和熟悉度的结论。最后结合人机工程学原则对GB/T24362—2009中的部分理解率较低的标志进行分析,提出了具体的改良设计建议。     

新疆天山地区的波速比异常分析

Based on the seismic observation report data provided by the Xinjiang Digital Seismic Network from 2009 to 2014,we calculate the wave velocity ratio and its background value for medium and small earthquakes by using the multi-station method in Tianshan,Xinjiang.This paper analyzes the variation of the wave velocity ratio disturbance value to highlight the abnormal,and also back-traces 7 moderate earthquakes at the research area.The results show that:(1)the background value of the wave velocity ratio is almost 1.70,the wave velocity ratio obviously decreases in the middle-eastern part of Tianshan and the region near the Puchang fault;(2)the wave velocity ratio disturbance value is mostly low in the epicenter before four earthquakes of M≥5.0 from 2011 to 2013 in the study area;(3)before 7 moderate strong earthquakes,the earthquake events with low value of the wave velocity ratio account for over 60% of corresponding total events near the epicenters,and the low value of the wave velocity ratio is relatively obvious before moderate earthquakes.     

The Co-seismic Response of Underground Fluid in Yunnan to the Nepal MS8.1 Earthquake

In this paper, statistics are taken on the co-seismic response of underground fluid in Yunnan to the Nepal M_S8.1 earthquake, and the co-seismic response characteristics of the water level and water temperature are analyzed and summarized with the digital data. The results show that the Nepal M_S8.1 earthquake had greater impact on the Yunnan region, and the macro and micro dynamics of fluids showed significant co-seismic response. The earthquake recording capacity of water level and temperature measurement is significantly higher than that of water radon and water quality to this large earthquake; the maximum amplitude and duration of co-seismic response of water level and water temperature vary greatly in different wells. The changing forms are dominated by fluctuation and step rise in water level, and a rising or falling restoration in water temperature. From the records of the main shock and the maximum strong aftershock,we can see that the greater magnitude of earthquake, the higher ratio of the occurrence of co-seismic response, and in the same well, the larger the response amplitude, as well as the longer the duration. The amplitude and duration of co-seismic response recorded by different instruments in a same well are different.Water temperature co-seismic response almost occurred in wells with water level response, indicating that the well water level and water temperature are closely related in co-seismic response, and the well water temperature seismic response was caused mainly by well water level seismic response.     

内蒙古中西部地区中小地震矩震级研究

基于S震相"S窗"内的波形信号识别、品质因子Q(f)和22个台站场地响应,利用2009~2016年3月内蒙古中西部地区地震的波形资料,反演了182次中小地震的震源波谱参数,得到这些小震的零频幅值及其拐角频率,据此计算了这些地震的地震矩M_0、矩震级M_W和应力降Δσ。利用回归分析方法得到了近震震级与矩震级、矩震级与应力降的关系式。分析表明,近震震级与矩震级、矩震级与应力降呈线性关系。可见,将矩震级纳入地震的快报与正式目录中,可以丰富地震观测报告内容,更好地为地震应急和地震科研服务。