共查询到19条相似文献，搜索用时 109 毫秒
1.
芦山7.0级地震强震动记录及其震害相关性 总被引：4，自引：0，他引：4
2013年4月20日芦山地震中的强震动记录是我国自2008年汶川地震后再一次比较全面地获得的高质量的数字强震动记录。国家数字强震动台网共获得3分量自由场记录114组,成都地震烈度速报台网获得63组。文章对强震动记录进行了常规处理,统计了强震动记录随断层距的数量分布情况,绘制了空间地震动加速度等值线图。结合芦山地震震源机制解和破裂过程研究成果,选取典型记录,分析加速度、速度时程的波形、振幅等特征,识别了此次地震滑冲现象,估算了竖向最大永久位移。通过利用观测数据与国外的地震动预测公式对比,分析了不同周期反应谱地震动幅值及加速度反应谱衰减规律,阐明了此次地震的地震动在近场高频成分较卓越的特点。震后现场考察了3个典型强震动台站附近建筑物震害,分析了地震动与工程震害的相关性,地震烈度的评定反映了地震破坏的程度。 相似文献
2.
我国强地震动记录特征综述 总被引：3，自引：1，他引：2
本文概述了我国强地震动台网的发展历程, 总结了唐山地震的强地震动记录特征和2007年以来我国数字台网获取的强地震动记录特征, 重点分析了近年来发生的几次典型破坏性地震的强地震动记录特征． 结果表明: 我国近场地震动记录体现了近场的方向性效应、 上/下盘效应、 速度脉冲、 局部场地效应等多样性特征, 可以进一步服务于地震工程领域的科学研究与工程应用． 相似文献
3.
本文对利用强震近场加速度记录确定时,空、强三个完整的震源参数。文中给出一种利用计算机自动识别地震记录的Ｐ波初动到时和Ｓ波震相到的算法。根据新近发表的Ｗｏｏｄ－Ａｎｄｅｒｓｏｎ地震仪器的最新参数,修牍正唐山地区量规函数。利用唐 山数字震观测台阵得到的近场加速度数据,计算了１０次地震的震源位置和震级,并对定位误差进行了综合分析,将强震台网测定的震源参数与地震台 相似文献
4.
2020年7月12日发生了唐山古冶5.1级地震，其强震动影响波及京津唐地区，特别是北京城区也出现了强烈的震感。中国强震动观测台网、国家地震烈度速报台网及典型建筑结构地震反应观测台阵获得大量的强震动记录。这次地震震级不大，但为地震科学研究提供了较为丰富的信息。基于获得的地震影响信息，可开展以下方面的研究:①利用地震附近及区域范围内地震烈度速报台网的密集观测记录，开展地震影响烈度快速计算分析及台网功能可靠性检测；②利用北京和天津地区的强震动观测记录，探讨深厚覆盖土层和盆地场地地震动影响；③利用京津唐地区震中距至300 km的强震动观测记录，研究京津唐地区的地震动衰减特性；④利用北京城区的建筑结构地震反应观测台阵记录，分析典型工程结构地震反应特征；⑤其他，如场地土层参数和工程结构参数反演研究等。本文针对以上关注的问题，介绍了相关初步研究工作并开展了进一步探讨性分析研究，展示了唐山古冶5.1级地震影响的丰富信息和对相关研究的潜在推进作用。 相似文献
5.
李惠智 《地震地磁观测与研究》2010,31(Z1)
宁夏数字强震动台网观测系统是国家重点建设的防震减灾基础设施项目,由48个数字观测台站和1个强震动台网中心组成.台站采用无人值守方式,利用电话拨号、CDMA和扩频微波以及卫星传输的方式,在台网中心与各强震台之间建立连接,实施远程监控.台网全部采用先进的数字技术,使宁夏强震动观测技术发生了质的变化, 填补了宁夏境内没有固定数字强震台站的空白,大幅度增强了获取近场强震动数据的能力.当宁夏发生4级以上地震时,可以获得多台强震动记录;同时,在监视区范围内发生3级以上地震时,亦可获得多台近场加速度记录,从而为震害快速评估和制定震后应急决策提供可靠依据. 相似文献
6.
2008年四川汶川8．0级地震强震动台网观测记录 总被引：8，自引：0，他引：8
本文简要阐述了2008年5月12日在四川汶川发生的8.0级地震中,四川强震台网的记录情况.在"十五"中国数字强震动观测网络分项目完成并通过台网验收后,四川省强震台网获取了该次地震的强地面运动记录,为震害评估和救灾提供了依据,并为四川省今后能获取高质量的强震动记录打下了良好的基础. 相似文献
7.
2020年10月22日11时03分37秒四川省绵阳市北川县发生MS4.7地震,四川强震动台网与预警烈度速报台网在震区建成较密集的台站,获取了532组三分量加速度记录,有助于开展区域地震动衰减和地震动特征研究.本文对强震记录进行常规处理后计算出强震动记录的相关参数,利用克里金插值方法得到地震动峰值加速度PGA和峰值速度PGV的空间分布图,长轴呈北西—南东方向.分析强震动记录PGA、PGV随距离的衰减规律,与常用衰减关系预测值进行对比,此次地震PGA的衰减特性与俞言祥和汪素云(2006)提出的中国西部地区水平向基岩加速度衰减关系有较好的一致性.北川MS4.7地震获得的密集强震动记录为建立区域衰减关系,以及开展基于经验格林函数方法(EGFM)再现大震强地震动场展布等研究提供了重要的数据支撑. 相似文献
8.
李永振 《地震地磁观测与研究》2011,32(2):42-46
2008年辽宁海城M 4.3地震,辽宁省强震动台网12个强震台站记录到地面运动,是辽宁省自开展强震动观测以来同时获取强震记录最多的一次,记录的最大加速度为167.5 cm·s-2,初步展现了辽宁省强震动台网建设的成效. 相似文献
9.
李永振 《地震地磁观测与研究》2011,32(6):42-46
2009年吉林伊通M4.3地震,辽宁省及吉林省强震动台网有8个强震台站记录到地面运动,记录的最大加速度为30.8 cm·s-2,初步展现了强震动台网建设的功效. 相似文献
10.
11.
近场强震数据是地震观测的主要数据类型之一，但尚未广泛用于震源参数快速和常规测定.作者利用2017年8月8日九寨沟地震的近场强震数据，分别基于中国地震台网中心和美国地质调查局的定位结果，采用迭代反褶积和叠加（Iterative Deconvolution and Stacking， IDS）方法反演得到了两个破裂模型.反演结果显示，两个破裂模型除在时间上存在大约2.5 s的偏移外，在其他破裂特征上都极其相似，表明强震数据反演并不严重依赖地震定位结果.破裂过程大约持续8~10 s，释放的地震矩在6.9×1018 Nm左右，对应的矩震级约为MW6.5.走向方向上，破裂覆盖了震中西北15 km至震中东南10 km的区域，整体表现为不对称的双侧破裂模式，其中西北方向的破裂略占优势.深度方向上，主要破裂集中在0~10 km的较浅区域.这些特征与目前的地震学和大地测量学结果基本一致，表明在当前的数据条件下，即使定位结果存在不确定性，通过反演强震数据也能够独立可靠地确定中强地震的破裂过程.特别地，未来强震数据的数据质量和获取效率得到进一步改进和提升后，这一工作有望成为震后快速确定破裂过程的主要方式之一，在震后应急工作中发挥积极作用. 相似文献
12.
Can Zulfikar Mustafa Erdik Erdal Safak Hikmet Biyikoglu Cagatay Kariptas 《Bulletin of Earthquake Engineering》2016,14(9):2565-2578
This paper describes a rapid response and risk mitigation system Istanbul Natural Gas Distribution Network Seismic Risk Reduction Project (IGRAS) for the Istanbul Natural Gas Network (IGDA?). Upon the trigger signal received from the earthquake early warning system in Istanbul, the real-time algorithm at IGRAS system district regulators checks the threshold levels of ground-motion parameters and interrupts the gas flow if any exceedance is detected. Then the system: (1) produces almost real-time earthquake hazard maps by using on-line strong-motion data from the strong-motion network in Istanbul: (2) estimates the distribution of damage to the natural gas network; and (3) transfers these damage distribution maps to stakeholders to enable dispatching rapid response teams to high damage areas. 相似文献
13.
Rupture process and aftershock focal mechanisms of the 2022 M6.8 Luding earthquake in Sichuan 
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下载免费PDF全文 According to the China Earthquake Networks Center, a strong earthquake of M6.8 occurred in Luding County, Ganzi Tibetan Autonomous Prefecture, Sichuan Province, China (102.08°E, 29.59°N), on September 5, 2022, with a focal depth of 16 km. Rapid determination of the source parameters of the earthquake sequence is vital for post-earthquake rescue, disaster assessment, and scientific research. Near-field seismic observations play a key role in the fast and reliable determination of earthquake source parameters. The numerous broadband seismic stations and strong-motion stations recently deployed by the National Earthquake Intensity Rapid Report and Early Warning project have provided valuable real-time near-field observation data. Using these near-field observations and conventional mid- and far-field seismic waveform records, we obtained the focal mechanism solutions of the mainshock and M ≥ 3.0 aftershocks through the waveform fitting method. We were further able to rapidly invert the rupture process of the mainshock. Based on the evaluation of the focal mechanism solution of the mainshock and the regional tectonic setting, we speculate that the Xianshuihe fault formed the seismogenic structure of the M6.8 strong earthquake. The aftershocks formed three spatially separated clusters with distinctly different focal mechanisms, reflecting the segmented nature of the Xianshuihe fault. As more high-frequency information has been applied in this study, the absolute location of the fault rupture is better constrained by the near-field strong-motion data. The rupture process of the mainshock correlates well with the spatial distribution of aftershocks, i.e., aftershock activities were relatively weak in the maximum slip area, and strong aftershock activities were distributed in the peripheral regions. 相似文献
14.
Reeves Whitney 《Bulletin of Earthquake Engineering》2018,16(10):4467-4495
A study of the coseismic displacement and fling pulse recorded during the Mw 6.5 30 October 2016 Central Italy earthquake is presented. The near-field has been well documented, owing to the deployment of additional strong-motion stations following the earlier events of the 2016 Central Italy seismic sequence. As a result, there are numerous stations with evidence of coseismic displacement and fling pulse. In this study, 25 records with strike distance of less than 25 km and rupture distance under 28 km are considered. Approximate coseismic displacements have been recovered by a bilinear model to remove the low frequency noise in the records. The bilinear noise model uses two linear regression segments on the velocity trace to remove baseline offsets. After obtaining the coseismic displacement time series, the fling pulse period is examined. Existing methods of obtaining the fling pulse period are reviewed and a proposed algorithm is considered for automatic fling pulse detection. Both horizontal and vertical fling periods are obtained, unlike many studies which neglect the vertical fling. It is shown that the fling pulse period is highly variable (~?2–16 s) in the near-field region but exhibits some trends with various site-to-source distances. 相似文献
15.
COSEISMIC DISPLACEMENT FIELD OF THE WENCHUAN EARTHQUAKE DERIVED FROM STRONG MOTION RECORDS AND APPLICATION IN SLIP INVERSION 下载免费PDF全文
下载免费PDF全文 The development of high-rate GNSS seismology and seismic observation methods has provided technical support for acquiring the near-field real-time displacement time series during earthquake. But in practice, the limited number of GNSS continuous stations hardly meets the requirement of near-field quasi-real-time coseismic displacement observation, while the macroseismographs could be an important complement. Compared with high-rate GNSS, macroseismograph has better sensitivity, higher resolution(100~200Hz)and larger dynamic range, and the most importantly, lower cost. However, baseline drift exists in strong-motion data, which limits its widespread use. This paper aims to prove the feasibility and reliability of strong motion data in acquiring seismic displacement sequences, as a supplement to high-rate GNSS.
In this study, we have analyzed the strong-motion data of Wenchuan MS8.0 earthquake in Longmenshan fault zone, based on the automatic scheme for empirical baseline correction proposed by Wang et al., which fits the uncorrected displacement by polynomial to obtain the fitting parameters, and then the baseline correction is completed in the velocity sequence. Through correction processing and quadratic integration, the static coseismic displacement field and displacement time series are obtained. Comparison of the displacement time series from the strong motions with the result of high-rate GPS shows a good coincidence. We have worked out the coseismic displacement field in the large area of Wenchuan earthquake using GPS data and strong motion data. The coseismic displacement fields calculated from GPS and strong motions are consistent with each other in terms of magnitude, direction and distribution patterns. High-precision coseismic deformation can provide better data constraint for fault slip inversion. To verify the influence of strong-motion data on slip distribution in Wenchuan earthquake, we used strong motion, GPS and InSAR data to estimate the stress drop, moment magnitude and coseismic slip model, and our results agreed with those of the previous studies. In addition, the inversion results of different data are different and complementary to some extent. The use of strong-motion data supplements the slip of the fault in the 180km segment and the 270~300km segment, thus making the inversion results of fault slip more comprehensive.
From this result, we can draw the following conclusions:1)Based on the robust baseline correction method, the use of strong motion data, as an important complement to high-rate GNSS, can obtain reliable surface displacement after the earthquake. 2)The strong motion data provide an effective method to study the coseismic displacement sequence, the surface rupture process and quick seismogenic parameters acquisition. 3)The combination of multiple data can significantly improve the data coverage and give play to the advantages of different data. Therefore, it is suggested to combine multiple data(GPS, strong motion, InSAR, etc.)for joint inversion to improve the stability of fault slip model. 相似文献
16.
本文提出一种利用单站GPS载波相位或多普勒观测数据,基于单站GPS测速法实时确定地震监测台站运动状态(速度)的新方法.针对2010年4月4日发生于墨西哥Baja California(32.259°N,115.287°W)北部的Mw7.2级EI-Mayor-Cucapah地震事件,选取震中邻近区域(200 km内)若干采样率为5 Hz的高频GPS观测站数据进行实验.结果表明:基于新方法所得测站速度结果能够很好地反映出地震期间监测台站的瞬时运动状态,测站P496和P744计算的速度结果与其并置强震仪观测结果具有很好的一致性. 相似文献
17.
Paolo Augliera Ezio D’Alema Simone Marzorati Marco Massa 《Bulletin of Earthquake Engineering》2010,8(5):1091-1104
The necessity of a dense network in Northern Italy started from the lack of available data after the occurrence of the 24th
November 2004, Ml 5.2, Salò earthquake. Since 2006, many efforts have been made by the INGV (Italian National Institute for Geophysic and Vulcanology), Department of Milano-Pavia (hereinafter INGV MI-PV), to improve the strong-motion monitoring of the Northern Italy regions.
This activity led to the installation of a strong-motion network composed by 20 accelerometers, 4 coupled with 20-bits Lennartz
Mars88 recorders, 12 coupled with 24-bits Reftek 130 recorders and 4 coupled with 24-bits Gaia2 recorders. The network allow
us to reduce, in the area under study, the average inter-distances between strong-motion stations from about 40 km (at November
2004) to 15 km. At present the network includes nine 6-channels stations where velocity sensors work together the strong-motion
ones. The data transmission is assured by modem-gsm, with the exception of four stations that send data in real time through
a TCP/IP protocol. In order to evaluate different site responses, the stations have been installed both in free field and
near (or inside) public buildings, located in the center of small villages. From June 2006 to December 2008 a dataset of 94
events with local magnitude range from 0.7 to 5.1 has been collected. An ad hoc data-processing system have been created in
order to provide, after each recorded event, engineering parameters such as peak ground acceleration (PGA) and velocity (PGV),
response spectra (SA and PSV), Arias and Housner intensities. Data dissemination is achieved through the web site , while the waveforms are distributed through the Italian strong motion database (). 相似文献
18.
利用自动经验基线校正方法,分析日本2008年岩手-宫城内陆Mw6.9地震震中周围密集强震动观测台网资料,快速解算出了同震位移场分布,并据此反演了震源滑动模型.经与GPS结果比较,两种不同方法给出的同震位移幅值、方向和总体分布特征较为接近.基于相同断层面参数反演的震源模型空间展布形态、主要滑动范围、平均和最大滑动量、滑动方向以及由模型计算的矩震级等均吻合较好,从而验证了方法的可行性.讨论了自动经验基线校正方法尚存在的问题和不足,为今后利用强震资料快速解算Mw6-7级及以上地震的同震位移场并反演震源滑动分布提供参考. 相似文献
19.
利用远震资料、近场强震资料和合成孔径雷达干涉同震形变资料确定了2017年8月9日精河MS6.6地震的断层面参数及震源破裂细节。为得到可靠的断层几何参数,发展了一套基于InSAR数据滑动分布反演的三维格点搜索流程,对本次地震断层面的走向、倾角和震源深度进行了格点搜索。结果显示,地震断层面走向为95°,倾角为47°,震源深度为14 km。基于搜索得到的断层模型进行破裂过程联合反演的结果显示:精河MS6.6地震为一次单侧破裂事件,最大滑动量约为0.8 m,滑动区域集中在断层面上震源以西5—15 km,沿倾向15—25 km,破裂主要发生在10 km深度以下区域。断层面上的平均滑动角为106°。整个破裂过程释放的标量地震矩为3.6×1018 N·m,对应矩震级为MW6.3。破裂过程持续约9 s,期间的破裂速度约为2.1—2.6 km/s。由于地震破裂主要集中在10 km以下,未来可能需要关注该区域0—10 km发生潜在地震的可能性。 相似文献