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Earthquake Science 2014年第2期27卷 209-215页

作者： Xuzhang Shen Yuanze Zhou Koki Idehara Xiuping Mei Kangsheng Xu Lanzhou Institute of seismology China Earthquake Administration Key lab of Computational Geodynamics of Chinese Academy of Sciences/College of Earth Science University of Chinese Academy of Sciences Earthquake Research Institute Tokyo University

The D＇＇ layer,which is located atop the core–mantle boundary,has long been an area of focus for global seismology studies. A widely used approach to study the discontinuities in the D＇＇ layer involves the use of the SdS phases between the S and ScS phases,which requires that certain stringent conditions be satisfied with respect to an epicentral distance and earthquake depth. Therefore,this approach is only practical for investigating the presence and topography of velocity interfaces in certain local regions around the world. The Russia–Kazakhstan border region has been a ‘‘blind spot＇＇ with respect to this detection method. The seismic network deployed in the northeastern margin of the Tibetan Plateau has recorded relatively clear SdS phases for the MS6.3 earthquake that occurred in Spain on April 11,2010,allowing this blind spot to be studied. This paper compares the observed waveforms and synthetics and uses the travel times of the relevant phases to obtain a D＇＇ discontinuity depth between2,610 and 2,740 km in the examined area. This study provides the first results regarding the depth of the D＇＇ layer discontinuity for this region and represents an important addition to the global studies of the D＇＇ layer.

关键词： D'' Russia-Kazakhstan border Spain deep earthquake North eastern margin of Tibet

The geodynamic significance of observed deformed lab and 410-km discontinuity beneath the eastern margin of the Tibet

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The geodynamic significance of observed deformed LAB and 410...

Development of a new high resolution waveform migration location method and its applications to induced seismicity

中国地球物理学会第二十九届年会

作者： Xuzhang Shen Xiaohui Yuan Rainer Kind Kumar Prakash Marcelo Bianchi Lanzhou Institute of seismology China Earthquake Administration

＜正＞The Sichuan Basin is located east of Tibet and confines its eastward extension. Based on the analysis of the topography of the Tibetan Plateau, Clark and Royden （2000） presented a model of a weak Tibetan crust and hard crust of the Sichuan Basin. The results from seismic tomography indicate that the contrast in rheological properties between the eastern Tibetan Plateau and the Sichuan basin may be related in part to the temperature

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Earth and Planetary Physics 2021年第6期5卷 520-531页

作者： SiYu Miao HaiJiang Zhang YuYang Tan Ye Lin laboratory of seismology and Earth’s Interior School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Mengcheng National Geophysical Observatory University of Science and Technology of ChinaHefei 230026China Key lab of Submarine Geosciences and Prospecting Techniques MOE Institute for Advanced Ocean StudyOcean University of ChinaQingdao 266100China laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266100China

Locating seismic events is a central task for earthquake *** to arrival-based location methods,waveformbased location methods do not require picking phase arrivals and are more suitable for locating seismic events with noisy *** waveform-based location methods,one approach is to stack different attributes of P and S waveforms around arrival times corresponding to potential event locations and origin times,and the maximum stacking values are assumed to indicate the correct event location and origin *** this study,to obtain a high-resolution location image,we improve the waveform-based location method by applying a hybrid multiplicative imaging condition to characteristic functions of seismic *** our new stacking method,stations are divided into groups;characteristic functions of seismic waveforms recorded at stations in the same group are summed,and then multiplied among *** find that this approach can largely eliminate the cumulative effects of noise in the summation process and thus improve the resolution of location *** test the new method and compare it to three other stacking methods,using both synthetic and real datasets that are related to induced seismicity occurring in petroleum/gas *** test results confirm that the new stacking method can provide higher-resolution location images than those derived from currently used methods.

关键词： induced earthquake seismic location seismic monitoring

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二维介质线性化声波反演

二维介质线性化声波反演

Downhole microseismic data reconstruction and imaging based on combination of spline interpolation and curveletsparse constrained interpolation

美国勘探地球物理学家学会第61届年会

作者： Gilles Lambaré Jean Virieux Raoul Madariaga Side Jin 牛毓荃 seismology lab Institut de Physique du Globe de Paris （IPG） Geodynamics Institute Centre National de la Recherche Scientifique （CNRS） IPG IPG

近来,作为地震反演战略（Beylkin和Burrige 1990;Jin等1991）,我们运用射线理论设计一种声波场的有效向下延拓法。在我们想要恢复地层图象的每一绕射点处估计渐近反演算子的各不同组成部分。该图象通过以同样的初始射线追踪为基础的迭...

近来,作为地震反演战略（Beylkin和Burrige 1990;Jin等1991）,我们运用射线理论设计一种声波场的有效向下延拓法。在我们想要恢复地层图象的每一绕射点处估计渐近反演算子的各不同组成部分。该图象通过以同样的初始射线追踪为基础的迭代方法得到改善。通过迭代处理,我们说取得了较好的反演效果,因为合成地震记录与实际地震记录吻合较好,一个一维介质合成实例表明精确的射线追踪对获得准确的反射层位置的有效性以及迭代法对获得精确的速度摄动量的重要性。另一个具有二维非均匀介质的实例表明,我们能够处理多次波波至,并且一旦一个平层上的速度摄动量已知,我们就可以几乎完美地恢复一平层介质的形态。最后,我们研究北海地区Oseberg剖面的实例。我们说明迭代渐近反演法是能够用现有计算机处理大量数据的一种可行且合理的方法。制作出的图象表明使用迭代法能增加最终图象的高频成分。

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Global Geology 2016年第1期19卷 26-32,40页

作者： CHANG Kai LIN Ye GAO Ji CHEN Yukuan ZHANG Jiewen College of Geo-Exploration Science and Technology Jilin University Wantai Microseismic lab of School of Earth and Space Sciences University Science and Technology of China laboratory of seismology and Physics of Earth's Interior University of Science and Technology of China

When using borehole sensors and microseimic events to image,spatial aliasing often occurred because of the lack of sensors underground and the distance between the sensors which were too large. To solve the aliasing problem,data reconstruction is often needed. Curvelet transform sparsity constrained inversion was widely used in the seismic data reconstruction field for its anisotropic,multiscale and local basis. However,for the downhole case,because the number of sampling point is much larger than the number of the sensors,the advantage of the curvelet basis can't perform very well. To mitigate the problem,the method that joints spline and curvlet-based compressive sensing was proposed. First,we applied the spline interpolation to the first arrivals that to be interpolated. And the events are moved to a certain direction,such as horizontal,which can be represented by the curvelet basis sparsely. Under the spasity condition,curvelet-based compressive sensing was applied for the data,and directional filter was also used to mute the near vertical noises. After that,the events were shifted to the spline line to finish the interpolation workflow. The method was applied to a synthetic model,and better result was presented than using curvelet transform interpolation directly. We applied the method to a real dataset,a microseismic downhole observation field data in Nanyang,using Kirchhoff migration method to image the microseimic event. Compared with the origin data,artifacts were suppressed on a certain degree.

关键词：样条插值数据重建基础井下 Curvelet变换微地震成像方向滤波器

Full moment tensor inversion constrained by doublecouple focal mechanism for induced seismicity

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Earthquake Science 2020年第4期33卷 177-193页

作者： Yuyang Tan Haijiang Zhang Junlun Li Chen Yin Furong Wu Key lab of Submarine Geosciences and Prospecting Techniques MOE College of Marine GeoscienceOcean University of ChinaQingdao 266100China laboratory of seismology and Physics of Earth’s Interiors School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China School of Environment and ResourceSouthwest University of Science and Technology Mianyang 621010China Bureau of Geophysical Prospecting INC. China National Petroleum CorporationChengdu 610213China

In this study,we propose a new method to determine full moment tensor solution for induced *** method generalizes the full waveform matching algorithm we have developed to determine the double-couple(DC)focal mechanism based on the neighbourhood *** major difference between the new method and the former one is that we adopt a new misfit function to constrain the candidate moment tensor solutions with respect to a reference DC solution in addition to other misfit terms characterizing the waveform *** synthetic tests using a real passive seismic survey geometry,the results show the new constraint can help better recover the DC components of inverted moment *** further investigate how errors in the velocity model and source location affect the moment tensor *** synthetic test results indicate that the constrained inversion is robust in recovering both the DC and non-DC *** also test the proposed method on several real induced events in an oil/gas field in Oman using the same observation system as synthetic *** it is found that the full moment tensor solutions without using the DC constraints have much larger non-DC components than solutions with the DC constraints,both solutions are able to fit the observed waveforms at similar *** synthetic and real test results suggest the proposed DC constrained inversion method can reliably retrieve full moment tensor solutions for the induced seismicity.

关键词： induced seismicity moment tensor double-couple waveform inversion neighbourhood algorithm

Morphology and possible origins of the Perm anomaly in the lowermost mantle of Earth

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Earth and Planetary Physics 2021年第1期5卷 105-116页

作者： YuMei He LianXing Wen Yann Capdeville Key laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Mohe Observatory of Geophysics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China laboratory of seismology and Physics of Earth’s Interior School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Department of Geosciences State University of New York at Stony BrookStony BrookNew YorkUSA laboratoire de Planétologie et Géodynamique de Nantes UMR6112CNRSUniversitéde NantesNantesFrance

We have constrained a small-scale,dome-shaped low-velocity structure near the core-mantle boundary(CMB)of Earth beneath Perm(the Perm anomaly)using travel-time analysis and three-dimensional(3-D)forward waveform modeling of seismic data sampling of the *** best-fitting dome-shaped model centers at 60.0°E,50.5°N,and has a height of 400 km and a radius that increases from 200 km at the top to 450 km at the *** velocity reduction varies from 0%at the top to–3.0%at 240km above the CMB to–3.5%at the CMB.A surrounding 240-km-thick high-velocity D''structure has also been *** Perm anomaly may represent a stable smallscale chemical pile in the lowermost mantle,although the hypothesis of a developing mantle plume cannot be ruled out.

关键词： seismic velocity structure core-mantle boundary Perm anomaly chemical pile

A joint absorbing boundary for the multiple-relaxation-time lattice Boltzmann method in seismic acoustic wavefield modeling

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Petroleum Science 2023年第4期20卷 2113-2126页

作者： Chun-Tao Jiang Hui Zhou Mu-Ming Xia Han-Ming Chen Jin-Xuan Tang State Key laboratory of Petroleum Resources and Prospecting CNPC Key Lab of Geophysical ExplorationChina University of PetroleumBeijing102249China CAS Engineering laboratory for Deep Resources Equipment and Technology Institute of Geology and Geophysicsand Innovation Academy for Earth ScienceChinese Academy of SciencesBeijing100029China Research Institute of Petroleum Exploration&Development PetroChinaBeijing100083China

Conventional seismic wave forward simulation generally uses mathematical means to solve the macroscopic wave equation,and then obtains the corresponding seismic ***,when the subsurface structure is finely constructed and the continuity of media is poor,this strategy is difficult to meet the requirements of accurate wavefield *** paper uses the multiple-relaxation-time lattice Boltzmann method(MRT-LBM)to conduct the seismic acoustic wavefield simulation and verify its computational *** cope with the problem of severe reflections at the truncated boundaries,we analogize the viscous absorbing boundary and perfectly matched layer(PML)absorbing boundary based on the single-relaxation-time lattice Boltzmann(SRT-LB)equation to the MRT-LB equation,and further,propose a joint absorbing boundary through comparative *** give the specific forms of the modified MRT-LB equation loaded with the joint absorbing boundary in the two-dimensional(2D)and three-dimensional(3D)cases,***,we verify the effects of this absorbing boundary scheme on a 2D homogeneous model,2D modified British Petroleum(BP)gas-cloud model,and 3D homogeneous model,*** results reveal that by comparing with the viscous absorbing boundary and PML absorbing boundary,the joint absorbing boundary has the best absorption performance,although it is a little bit ***,this joint absorbing boundary better solves the problem of truncated boundary reflections of MRT-LBM in simulating seismic acoustic wavefields,which is pivotal to its wide application in the field of exploration seismology.

关键词： Multiple-relaxation-time Lattice Boltzmann method Seismic acoustic wavefield simulation Truncated Boundary reflection Joint absorbing boundary

Temporal and spatial distribution of microfractures in granites of different structures under triaxial compression and its significance in seismology

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Chinese Science Bulletin 1999年第14期44卷 1321-1325页

作者： Liqiang Liu Shengli Ma Jin Ma Xinglin Lei K. Kusunose O. Nishizawa L. Jouniaux China Seismol Bur Inst Geol Beijing 100029 Peoples R China Geol Survey Japan Tsukuba Ibaraki 305 Japan Ecole Normale Super Geol Lab F-75231 Paris France CNRS URA 1316 Paris France

The temporal and spatial distribution of microfracturing activity in two kinds of granite under triaxial compression has been studied by using a new acoustic emission system. For Inada granite, there is no clear clustering of acoustic emission events in time and space, thus it is difficult to exactly deduce the time and position of the major fracturing. While for Mayet granite,acoustic emission events are clustered in time and space, so the time and position of the major fracturing can be exactly predicted according to microfracturing process. Such a difference may result from the difference in deformation mode caused by different rock structures.

关键词： rock structure acoustic emission microfracturing temporal and spatial distribution seismicity.

MHD seismology of a loop-like filament tube by observed kink waves

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Research in Astronomy and Astrophysics 2015年第10期15卷 1713-1724页

作者： Vaibhav Pant Abhishek K Srivastava Dipankar Banerjee Marcel Goossens Peng-Fei Chen Navin Chandra Joshi Yu-Hao Zhou Indian Institute of Astrophysics Department of Physics Indian Institute of Technology(BHU) Center of Excellence in Space Sciences Centre for Mathematical Plasma Astrophysics Department of Mathematics School of Astronomy and Space Science Nanjing University Key lab of Modern Astronomy and Astrophysics Nanjing University School of Space Research Kyung Hee University

We report and analyze observational evidence of global kink oscillations in a solar filament as observed in Ha by instruments administered by National Solar Observatory （NSO）/Global Oscillation Network Group （GONG）. An M1.1-class flare in active region （AR） 11692 occurred on 2013 March 15 and induced a global kink mode in the filament lying towards the southwest of AR 11692. We find periods of about 61-67 minutes and damping times of 92-117 minutes at positions of three ver- tical slices chosen in and around the filament apex. We find that the waves are damped. From the observed period of the global kink mode and damping timescale using the theory of resonant absorption, we perform prominence seismology. We estimate a lower cut-off value for the inhomogeneity length scale to be around 0.34-0.44 times the radius of the filament cross-section.

关键词： Sun: oscillations -- Sun: magnetic fields -- Sun: filament