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Doppler effect in high-speed rail seismic wavefield and its application

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Science China Earth Sciences 2022年第3期65卷 414-425页

作者： Yiran JIANG jieyuan ning Jingchong WEN Yongxiang SHI School of Earth and Space Sciences Peking UniversityBeijing 100871China Hongshan Geophysical National Observation and Research Station Beijing 100871China

We demonstrate by theoretical analysis that periodically distributed viaduct piers of high-speed rail result in the Doppler effect in the seismic wavefield of high-speed rail at specific frequencies and analyze the Doppler effect’s influence on the wavefield’s spectrum feature.We further verify our theoretical prediction by using observational data of the high-speed rail seismic wavefield in Rongcheng,Hebei Province,China.We find that the wavefield component with a noticeable Doppler effect vibrates in the propagation direction and only has a unique apparent wave speed,indicating that P-wave is dominant.Furthermore,we propose a speed measurement method based on the Doppler effect and measure the wave speed of the medium along the rail.Measurement results are highly stable and consistent.

关键词： High-speed rail seismic wavefield Spectrum feature Doppler effect Doppler velocity measurement

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关于高铁地震波场虚拟道集生成的理论分析

地球物理学报 2024年第1期67卷 251-260页

作者：殷常阳石永祥伍晗温景充宁杰远北京大学地球与空间科学学院北京100871 河北红山巨厚沉积与地震灾害国家野外科学观测研究站北京100871 自然资源部深地科学与探测技术实验室北京100094

中国约80%的高铁运行于高架桥上,高铁振动通过桥墩传入地面.本文对运行于等间隔桥墩的高架桥上高铁振动产生的地下地震波场形态进行了理论分析,根据其在特定方向形成相干相位稳相点区域的特征,设计了一种基于多个不同速度高铁列车振动... 详细信息

中国约80%的高铁运行于高架桥上,高铁振动通过桥墩传入地面.本文对运行于等间隔桥墩的高架桥上高铁振动产生的地下地震波场形态进行了理论分析,根据其在特定方向形成相干相位稳相点区域的特征,设计了一种基于多个不同速度高铁列车振动记录叠加,分离单桥墩激发虚拟地震波场的方法,并对单层与多层介质的情形进行了理论验证.

关键词：高铁地震学稳相点干涉场虚拟道集

Focal Mechanism Solutions of the 2008 Wenchuan earthquake sequence from P-wave polarities and SH/P amplitude ratios:new results and implications

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Earthquake Science 2013年第6期26卷 357-372页

作者： Yuan Tian jieyuan ning Chunquan Yu Chen Cai Kai Tao Institute of Theoretical and Applied Geophysics School of Earth and Space SciencesPeking University Department of Earth Atmospheric and Planetary SciencesMIT Department of Earth & Planetary Sciences Washington University

Abstract The 2008 Wenchuan earthquake, a major intraplate earthquake with Mw 7.9, occurred on the slowly deforming Longmenshan fault. To better understand the causes of this devastating earthquake, we need knowledge of the regional stress field and the underlying geodynamic processes. Here, we determine focal mechanism solutions （FMSs） of the 2008 Wenchuan earthquake sequence （WES） using both P-wave first-motion polarity data and SH/P amplitude ratio （AR） data. As P-wave polarities are more reliable information, they are given priority over SH/ PAR, the latter of which are used only when the former has loose constraint on the FMSs. We collect data from three categories：（1） permanent stations deployed by the China Earthquake Administration （CEA）; （2） the Western Sichuan Passive Seismic Array （WSPSA） deployed by Institute of Geology, CEA; （3） global stations from Incorporated Research Institutions for Seismology. Finally, 129 events with magnitude over Ms 4.0 in the 2008 WES are identified to have well-constrained FMSs. Among them, 83 are well constrained by P-wave polarities only as shown by Cai et al. （Earthq Sci 24（1）：115-125,2011）, and the rest of which are newly constrained by incorporating SH/P AR. Based on the spatial distribution and FMSs of the WES, we draw following conclusions：（1） the principle compressional directions of most FMSs of the WES are subhorizontal, generally in agreement with the conclusion given by Cai et al. （2011） but with a few modifications that the compressional directions are WNW-ESE around Wenchuan and ENE-WSW around Qingchuan, respectively. The subhorizontal compressional direction along the Longmenshan fault from SW to NE seems to have a leftlateral rotation, which agrees well with regional stress field inverted by former researchers （e.g., Xu et al., Acta Seismol Sin 30（5）, 1987; Acta Geophys Sin 32（6）, 1989; Cui et al., Seismol Geol 27（2）：234-242, 2005）; （2） the FMSs of the events not only reflected the regional stress state of the Longmenshan region, but also were obviously co

关键词： Longmenshan fault Wenchuan earthquakesequence Focal mechanism solutions Stress

Spatial distribution and focal mechanism solutions of the Wenchuan earthquake series:Results and implications

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Earthquake Science 2011年第1期24卷 115-125页

作者： Chen Cai Chunquan Yu Kai Tao Xingping Hu Yuan Tian Hao Zhang Xiaofeng Cui jieyuan ning School of Earth and Space Sciences Peking University Beijing 100871 China Department of Earth Atmospheric and Planetary Sciences MIT Cambridge MA 01239 USA Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China

We relocate the spatial distribution of its aftershocks. The relocation database is obtained the devastating 12 May 2008 Wenchuan earthquake and from 89 stations deployed by the China Earthquake Administration, including 54 525 seismograms from 1 376 local earthquakes over Ms3.5 between 12 May 2008 and 3 August 2008. The cross-correlation technique used in this paper has greatly improved the relocation precision by giving much more accurate P-wave differential travel-time measurements than those obtained from routinely picked phase onsets. At the same time, we pick P-wave polarity observations of the Wenchuan earthquake series （hereafter referred to as WES） from 1023 stations in China and 59 IRIS （Incorporated Research Institutions of Seismology） stations. Then, employing a newly developed program CHNYTX, we obtain 83 well-determined focal mechanism solutions （hereafter referred to as FMSs）. Based on spatial distribution and FMSs of the WES, we draw following conclusions：（1） The region near the main shock exhibits a buried low-angle northwest-dipping seismic zone with the main shock at its upper end and two conjugated seismic zones dipping southeast with roughly equal dip-angle; （2） The compressional directions of all kinds of FMSs of the WES are subhorizontal, which reflects the dominant stress in this area is eompressional; （3） The principal compressional direction of the regional stress around Wenchuan is roughly perpendicular to the strike of Beichuan-Yingxiu fault, while around Qingchuan it is roughly parallel to the strike of Qingehuan fault. In intermediate part of the Longmenshan area, the principal compressional direction of the stress should be in-between; （4） The possibly existed molten materials in the lower crust of Songpan-Garze terrain have small contribution to the local stress state in Longmenshan area. The listric geometries of the Longmenshan faults most probably resulted from subhorizontal compression along NW-SE direction in history.

关键词： seismotectonics stress state relocation focal mechanism solution Wenchuan

Crust and upper mantle structures beneath Northeast China from receiver function studies

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Earthquake Science 2014年第3期27卷 265-275页

作者： Zhen Guo Yuliang Cao Xianguang Wang Y.John Chen jieyuan ning Weiguang He Youcai Tang Yongge Feng School of Earth and Space Sciences Institute of Theoretical and Applied Geophysics (ITAG)Peking University State Key Laboratory of Petroleum Resource and Prospecting and Unconventional Natural Gas InstituteChina University of Petroleum

P-wave and S-wave receiver function analyses have been performed along a profile consisted of 27 broadband seismic stations to image the crustal and upper mantle discontinuities across Northeast China. The results show that the average Moho depth varies from about 37 km beneath the Daxing＇anling orogenic belt in the west to about 33 km beneath the Songliao Basin, and to about 35 km beneath the Changbai mountain region in the east. Our results reveal that the Moho is generally flat beneath the Daxing＇anling region and a remarkable Moho offset （about 4 km） exists beneath the basin-mountain boundary, the Daxing＇anling-Taihang Gravity Line. Beneath the Tanlu faults zone, which seperates the Songliao Basin and Changbai region, the Moho is uplift and the crustal thick- ness changes rapidly. We interpret this feature as that the Tanlu faults might deeply penetrate into the upper mantle, and facilitate the mantle upwelling along the faults during the Cenozoic era. The average depth of the lithosphereasthenosphere boundary （LAB） is - 80 km along the profile which is thinner than an average thickness of a continental lithosphere. The LAB shows an arc-like shape in the basin, with the shallowest part approximately beneath the center of the basin. The uplift LAB beneath the basin might be related to the extensive lithospheric stretching in the Mesozoic. In the mantle transition zone, a structurally complicated 660 km discontinuity with a maximum 35 km depression beneath the Changbai region is observed. The 35 km depression is roughly coincident with the location of the stagnant western pacific slab on top of the 660 km discontinuity revealed by the recent P wave tomography.

关键词： Northeast China NCC - Receiver function Migration - CCP - Moho - LAB Mantle transition zone

Mantle anisotropy across the southwestern boundary of the Ordos block,North China

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Earthquake Science 2010年第6期23卷 549-553页

作者： Yongcai Tang Yongshun John Chen Yuanyuan V. Fu Haiyang Wang Shiyong Zhou Eric Sandvol jieyuan ning Yongge Feng Mian Liu Department of Geophysics School of Earth and Space Sciences Peking University Beij'ing 100871 China Department of Geological Sciences University of Missouri Columbia MO 65211 USA

Located at the northeastern margin of the Tibetan plateau,the Ordos block is a stable tectonic unit in North China.With its active boundary fault zones,the Ordos block played an important role in the eastward extrusion mechanism of the Tibetan plateau.Peking University deployed a linear array of 15 portable broadband seismometers across the western Weihe graben during September 2005 to August 2006 and later a 2-D seismic array（Southwest Ordos Array） of 14 portable broadband seismometers during 2007-2008 at its southwestern boundary.Analyses of shear wave splitting of SKS and SKKS phases at these stations show that the fast directions trend ～110° with an average delay time of 0.9 s in the southwestern margin of the Ordos block.The agreement between the lithosphere deformation indicated by GPS data and Quaternary fault slip-rate observations and the mantle flow represented by shear wave splitting implies that accordant deformation patterns from lithosphere to asthenosphere in relation to the eastward extrusion of the Tibetan plateau could extend at least to 200 km depth.Spatial distribution of splitting polarization directions indicates that the mantle flow driven by the Tibetan plateau is blocked by the Ordos block and locally restricted in a narrow channel along the Qinling-Dabie fault zones between the Ordos block and Sichuan basin.

关键词： shear wave splitting Weihe graben Ordos mantle anisotropy

Intermediate-depth earthquakes beneath the Pamir-Hindu Kush Region:Evidence for collision between two opposite subduction zones

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Earthquake Science 2009年第6期22卷 659-665页

作者： Xiaoting Lou Chen Cai Chunquan Yu jieyuan ning Department of Geophysics School of Earth and Space Sciences Peking University Beijing 100871 China

We employed a double-difference algorithm （hypoDD） to relocate earthquakes within the region bounded by 66°E-78°E and 32°N-42°N in the period of 1964-2003 reported by the International Seismological Center （ISC）. The improved hypocentral locations delineate a double-layered Wadati-Benioff zone in the eastern Hindu Kush intermediate seismic belt. Based on this feature and other evidences, we propose that the intermediate-depth earthquakes beneath the Pamir-Hindu Kush region may occur in two collided subduction zones with opposite dip directions.

关键词： continental dynamics Pamir-Hindu Kush intermediate seismic zone earthquake relocation

基于程函方程与三维速度模型的中国东北地区地幔过渡带接收函数研究

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地球物理学报 2022年第8期65卷 2945-2959页

作者：张炎钮凤林宁杰远北京大学地球与空间科学学院北京100871 美国莱斯大学地球、环境与行星科学系休斯顿770053 中国石油大学石油资源与勘探国家重点实验室和非常规天然气研究所北京102249 河北红山巨厚沉积与地震灾害国家野外科学观测研究站北京100871

本文利用中国东北地区NECESSArray记录到的45505条接收函数,结合该区域最新三维速度模型,采用快速行进法求解程函方程,计算了P-S转换波相对走时,并通过共转换点叠加成像方法获得了该地区下方地幔间断面起伏情况.结果显示,在长白山—五... 详细信息

本文利用中国东北地区NECESSArray记录到的45505条接收函数,结合该区域最新三维速度模型,采用快速行进法求解程函方程,计算了P-S转换波相对走时,并通过共转换点叠加成像方法获得了该地区下方地幔间断面起伏情况.结果显示,在长白山—五大连池连线一带东西约300 km,南北约900 km的狭长形区域内,660-km间断面下陷幅度达20~40 km.其结构可细分为南北两部分,南部更为狭窄且与日本海沟走向一致,对应于从日本海沟俯冲的太平洋板块在地幔过渡带的滞留区;北部对应于从千岛海沟俯冲的太平洋板块在地幔过渡带的滞留区.同时,在长白山西部,存在与长白山—五大连池下陷区形状类似的南北向狭长形抬升区,660-km间断面抬升幅度约为10 km,显示俯冲太平洋板块只延伸至松辽盆地东侧;而在盆地西侧,660-km间断面的下陷区可能与该地区岩石圈拆沉有关.同时,410-km间断面在松辽盆地—渤海一带,以及长白山火山西南和东北方向存在明显的下陷区;另外,在阿巴嘎及阿尔山也有小范围的下陷区.所有这些下陷区,均与地表新生代火山活动区/拉伸区有很好的对应关系,表明这些地表构造与深部热物质上涌有关.

关键词：中国东北接收函数地幔过渡带新生代火山俯冲带

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虚拟地震台阵双差测深法及应用

北京大学学报（自然科学版） 2022年第4期58卷 615-625页

作者：鲍铁钊宁杰远北京大学地球与空间科学学院北京100871 河北红山地球物理国家野外科学观测研究站邢台054000

提出虚拟地震台阵双差测深法。通过多道互相关,测量密集观测台阵中相邻台站间SsPmp波与Ss波到时差的差值,然后求解最小二乘意义下每个台站SsPmp波与Ss波的到时差。该方法利用台阵优势,可以有效地降低到时差测量误差,有利于准确地估计地... 详细信息

提出虚拟地震台阵双差测深法。通过多道互相关,测量密集观测台阵中相邻台站间SsPmp波与Ss波到时差的差值,然后求解最小二乘意义下每个台站SsPmp波与Ss波的到时差。该方法利用台阵优势,可以有效地降低到时差测量误差,有利于准确地估计地壳厚度。将该方法应用在模拟数据和“中国地震科学台阵探测计划”台阵数据上,测量精度显著提高。

关键词：虚拟地震测深法(VDSS) 台阵多道互相关双差 Ss到时异常