Chinese Journal of Geophysics最新文献_第9页

SEISMOGENIC MECHANISM OF THE 21 JANUARY 2016 MENYUAN, QINGHAI MS6.4 EARTHQUAKE 2016年1月21日青海门原6.4级地震发震机制

Chinese Journal of Geophysics Pub Date : 2016-08-01 DOI: 10.1002/cjg2.20227

HU Chao-Zhong, YANG Pan-Xin, LI Zhi-Min, HUANG Shuai-Tang, ZHAO Yan, CHEN Dan, XIONG Ren-Wei, CHEN Qing-Yu

{"title":"SEISMOGENIC MECHANISM OF THE 21 JANUARY 2016 MENYUAN, QINGHAI MS6.4 EARTHQUAKE","authors":"HU Chao-Zhong, YANG Pan-Xin, LI Zhi-Min, HUANG Shuai-Tang, ZHAO Yan, CHEN Dan, XIONG Ren-Wei, CHEN Qing-Yu","doi":"10.1002/cjg2.20227","DOIUrl":"10.1002/cjg2.20227","url":null,"abstract":"On January 21, 2016, an MS6.4 earthquake occurred in Menyuan county, Qinghai province. Field investigations suggest that the long axis of the elliptical affected area is N120°-140°E. Comparative interpretations of high resolution remote sensing images before and after the shock show more than 23 sites of landslides and collapses, which are more distributed in the north of epicenter than in the south, extending in NNW overall. As the Lenglong Ling fault (LLF) is dominated by horizontal movement from high resolution remote images and field observation, it should not be responsible for this event of pure thrusting. North of the Lenglong Ling fault, there is a fault striking in 140°, which is north-dipping on the surface according to high resolution remote sensing, similar to the nodal plane I of focal mechanism solutions from deferent institutes. The long axis' direction of the overall distribution of aftershocks has also a difference of 20° with LLF, while almost parallel to the fault on its north. Thus, we infer that this fault is most likely the seismogenic structure of the Menyuan earthquake. Integrating the characteristics of aftershock distribution at depth, main shock focal mechanism solutions, geometric distribution and activity of the seismogenic fault on surface, in combination with the magnetotelluric sounding and related geophysical data around the earthquake zone, a cartoon model of the seismogenic mechanism is established. We speculate this earthquake is one of the events occurring during the pushing growth process of the Tibetan Plateau blocks in NE direction following the 2008 MS7.4 and 2014 MS7.3 earthquakes in Yutian, Xinjiang.","PeriodicalId":100242,"journal":{"name":"Chinese Journal of Geophysics","volume":"59 3","pages":"211-221"},"PeriodicalIF":0.0,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/cjg2.20227","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51223147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 19

SUPPRESSION OF SEISMIC RANDOM NOISE BASED ON STEERABLE FILTERS 基于可控滤波器的地震随机噪声抑制

Chinese Journal of Geophysics Pub Date : 2016-08-01 DOI: 10.1002/cjg2.20229

HUANG Mei-Hong, LI Yue

引用次数: 1

SEISMIC DETECTION OF A LOW-VELOCITY ANOMALY UNDER THE STAGNANT SLAB BENEATH THE EASTERN NORTH CHINA CRATON WITH THE P-WAVE TRIPLICATION 华北克拉通东部阻流板下低速异常的p波三叠法地震探测

Chinese Journal of Geophysics Pub Date : 2016-08-01 DOI: 10.1002/cjg2.20233

CUI Hui-Hui, ZHOU Yuan-Ze, SHI Yao-Lin, WANG Xiao-Ran, LI Guo-Hui

引用次数: 2

A DIRECT ESTIMATION METHOD FOR THE RUSSELL FLUID FACTOR BASED ON STOCHASTIC SEISMIC INVERSION 基于随机地震反演的罗素流体因子直接估计方法

Chinese Journal of Geophysics Pub Date : 2016-08-01 DOI: 10.1002/cjg2.20230

SUN Rui-Ying, YIN Xing-Yao, WANG Bao-Li, ZHANG Guang-Zhi

引用次数: 5

CHANGE DETECTION OF MULTI-TEMPORAL REMOTE SENSING IMAGES BASED ON CONTOURLET TRANSFORM AND ICA 基于contourlet变换和ica的多时相遥感图像变化检测

Chinese Journal of Geophysics Pub Date : 2016-08-01 DOI: 10.1002/cjg2.20231

WU Yi-Quan, CAO Zhao-Qing, TAO Fei-Xiang

{"title":"CHANGE DETECTION OF MULTI-TEMPORAL REMOTE SENSING IMAGES BASED ON CONTOURLET TRANSFORM AND ICA","authors":"WU Yi-Quan, CAO Zhao-Qing, TAO Fei-Xiang","doi":"10.1002/cjg2.20231","DOIUrl":"10.1002/cjg2.20231","url":null,"abstract":"In order to improve the accuracy and computational efficiency of change detection of multi-temporal remote sensing images, a change detection algorithm based on contourlet transform and independent component analysis (ICA) is proposed. Firstly, multi-scale decomposition of image data is performed by using contourlet transform with multi-scale, directionality and anisotropy. Then independent component analysis is carried out for the decomposed data. And the independent data components are separated by the improved fixed point ICA algorithm based on Newton iteration. Next the separated data components are transformed into image components. Finally, change detection is achieved by threshold segmentation and filtering for change image components. The experimental results show that, compared with the existing three change detection algorithms such as the algorithm based on PCA, the algorithm based on ICA and the algorithm based on wavelet transform and ICA, the proposed algorithm in this paper more effectively separates change information and reduces computational complexity. The obtained change image has higher accuracy and strong robustness with respect to the background.","PeriodicalId":100242,"journal":{"name":"Chinese Journal of Geophysics","volume":"59 3","pages":"255-265"},"PeriodicalIF":0.0,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/cjg2.20231","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51223752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

CHANNEL ANALYSIS OF EM-MWD BASED ON NMM 基于NMM的em-mwd信道分析

Chinese Journal of Geophysics Pub Date : 2016-06-16 DOI: 10.1002/cjg2.20222

FAN Ye-Huo, LI Wei, NIE Zai-Ping, YANG Zhi-Qiang, SUN Xiang-Yang

引用次数: 2

NOISE SUPPRESSION OF RECEIVER FUNCTIONS USING CURVELET TRANSFORM 利用曲波变换对接收函数进行噪声抑制

Chinese Journal of Geophysics Pub Date : 2016-06-16 DOI: 10.1002/cjg2.20219

QI Shao-Hua, LIU Qi-Yuan, CHEN Jiu-Hui, GUO Biao

{"title":"NOISE SUPPRESSION OF RECEIVER FUNCTIONS USING CURVELET TRANSFORM","authors":"QI Shao-Hua, LIU Qi-Yuan, CHEN Jiu-Hui, GUO Biao","doi":"10.1002/cjg2.20219","DOIUrl":"10.1002/cjg2.20219","url":null,"abstract":"Suppressing the scattering induced by the laterally heterogeneous media is important for imaging the crustal structure and its anisotropy from Receiver Functions (RFs) based on the laterally stratified model. Although the scattering can be suppressed, to some degree, with stacking technique or low-pass filtering, these may lead to undesired waveform distortion, information loss or resolution reduction. To avoid these problems, we make use of the curvelet transform technique, which is developing rapidly in recent years, to reduce the scattering field in the RFs. Unlike exploration seismology, our major challenge comes from the spatially nonuniform sampling of RFs, caused by the spatially incomplete and uneven distribution of stations and events. To overcome these difficulties, we combine the compressed sensing theory with the curvelet-based denoising method to realize the denoising and wavefield reconstruction, simultaneously. To verify our idea, we have tested the denoising and wavefield reconstruction with synthetic RFs and then apply our method to the observed data at one of the IRIS GSN stations and the western Sichuan array, respectively. The results show that: 1) our method is efficient in suppressing the scattering induced by the lateral heterogeneity of the crust, which leads to great improvement of the signal-to-noise ratio and spatial traceability of the RFs. This is valuable for the waveform imaging of the crustal structure and anisotropic parameters from the RFs; 2) the missing data caused by the event distribution can be correctly reconstructed; 3) our method can be applied to either single station or seismic array observations, but it is more efficient in single station observation than the seismic array study.","PeriodicalId":100242,"journal":{"name":"Chinese Journal of Geophysics","volume":"59 2","pages":"125-138"},"PeriodicalIF":0.0,"publicationDate":"2016-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/cjg2.20219","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51222822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

THE ELECTRON DENSITY PROFILE INVERSION FOR INCOMPLETELY DEVELOPED CASE OF F1 LAYER f1层不完全发育情况下的电子密度剖面反演

Chinese Journal of Geophysics Pub Date : 2016-06-16 DOI: 10.1002/cjg2.20217

WEI Na, LIU Wen, LU Zhuan-Xia, FENG Jing, YANG Long-Quan, GUO Wen-Ling

{"title":"THE ELECTRON DENSITY PROFILE INVERSION FOR INCOMPLETELY DEVELOPED CASE OF F1 LAYER","authors":"WEI Na, LIU Wen, LU Zhuan-Xia, FENG Jing, YANG Long-Quan, GUO Wen-Ling","doi":"10.1002/cjg2.20217","DOIUrl":"10.1002/cjg2.20217","url":null,"abstract":"The electron density profile inversion from vertical incidence ionograms is essential for research in ionospheric structures and movements, wave propagation and space weather applications, hence has gathered very wide attention. The echo trace of incompletely developed F1 layer is common in vertical incidence ionograms, and it is usually expressed as smooth transition from F1 layer to F2 layer, not a cusp appeared at the critical frequency of F1 layer. However, the existing ionospheric models and inversion algorithms are generally intended for the completely developed F1 layer with the assumptions of a parabolic profile and an infinite slope at the peak of F1 layer, which are not suitable for the profile of incompletely developed F1 layer which achieves the maximum electron density of F1 layer and enters F2 layer at the peak of F1 layer and has a finite slope. Consequently, an F1 layer electron density profile model based on the shifted Chebyshev polynomial for incompletely developed case of F1 layer is introduced with a parameter named as the model setting critical frequency. Taking into account the profile smoothness, an electron density profile inversion algorithm with constrained optimization F1 and F2 layer parameters based on the model mentioned above is proposed. The validity of the model and the inversion algorithm is analyzed through the simulation, and the effectivity of the proposed algorithm is further verified by the comparison between the synthesized vertical sounding & oblique sounding traces and the measured data.","PeriodicalId":100242,"journal":{"name":"Chinese Journal of Geophysics","volume":"59 2","pages":"101-117"},"PeriodicalIF":0.0,"publicationDate":"2016-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/cjg2.20217","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51222729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

ANALYSIS OF NORMALIZED TIME-FREQUENCY RESPONSE SPECTRA FOR THREE SEISMIC RECORDS 三次地震记录归一化时频响应谱分析

Chinese Journal of Geophysics Pub Date : 2016-06-16 DOI: 10.1002/cjg2.20223

QIU Zhi-Gang, LUO Qi-Feng

{"title":"ANALYSIS OF NORMALIZED TIME-FREQUENCY RESPONSE SPECTRA FOR THREE SEISMIC RECORDS","authors":"QIU Zhi-Gang, LUO Qi-Feng","doi":"10.1002/cjg2.20223","DOIUrl":"10.1002/cjg2.20223","url":null,"abstract":"Time-Frequency Response Spectrum (TFRS) is a three-dimensional spectrum, which includes three main characteristics of ground motion: amplitude, frequency characteristic and duration. Based on it, Normalized Time-Frequency Response Spectrum (NTFRS) was proposed and the NTFRS of three typical seismic waves were calculated. The comparison of three NTFRS shows that spectra amplitudes distributed along period axis and duration axis are different from each other; the large difference may cause different effect on the structures. One 12-storey reinforced concrete frame structure was analyzed by using elastic-plastic time-history analysis method. The comparison of the seismic response, structural damage curve and NTFRS of input ground motion shows that the maximum seismic response of structure might not be the cause of its collapse. It implies that the traditional response spectrum theory has limitation because in the theory the maximum elastic response of structures is used to make seismic design. It could be concluded that the Normalized Time-Frequency Response Spectrum is better for analyzing the characteristics of ground motions and the structural failure mechanism in the earthquakes.","PeriodicalId":100242,"journal":{"name":"Chinese Journal of Geophysics","volume":"59 2","pages":"172-179"},"PeriodicalIF":0.0,"publicationDate":"2016-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/cjg2.20223","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51223396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

USING OBS TELESEISMIC RECEIVER FUNCTIONS TO INVERT THE LITHOSPHERIC STRUCTURE—A CASE STUDY OF THE SOUTHWESTERN SUBBASIN IN THE SOUTH CHINA SEA 利用obs远震接收函数反演岩石圈结构——以南海西南次海盆为例

Chinese Journal of Geophysics Pub Date : 2016-06-16 DOI: 10.1002/cjg2.20226

HU Hao, RUAN Ai-Guo, YOU Qin-Yu, LI Jia-Biao, HAO Tian-Yao, LONG Jiang-Ping

{"title":"USING OBS TELESEISMIC RECEIVER FUNCTIONS TO INVERT THE LITHOSPHERIC STRUCTURE—A CASE STUDY OF THE SOUTHWESTERN SUBBASIN IN THE SOUTH CHINA SEA","authors":"HU Hao, RUAN Ai-Guo, YOU Qin-Yu, LI Jia-Biao, HAO Tian-Yao, LONG Jiang-Ping","doi":"10.1002/cjg2.20226","DOIUrl":"10.1002/cjg2.20226","url":null,"abstract":"Due to the particular seafloor environment and the special outer mechanical structure of the ocean bottom seismometer (OBS), there are some problems that have not been solved in the lithospheric structure inversion using the OBS teleseismic receiver functions. Based on the analysis of these problems, we combined the Fourier transform and wavelet analysis to suppress the non-stationary noise to obtain a better signal-to-noise ratio and clearer seismic phases recorded by the OBSs at the southwestern subbasin in the South China Sea (SCS). The equipment is a broadband OBS of I-4C type produced by the Institute of Geology and Geophysics, Chinese Academy of Sciences. We then inverted the lithospheric structure by successfully applying the receiver functions to the teleseismic data recorded at the southwestern subbasin in the SCS. The results show that it is feasible to use the receiver functions for the inversion of the lithosphere structure based on the passive observation data collected via the OBS, in which the key is to suppress the non-stationary noise. The Moho depth at the southwestern subbasin in the SCS is 10∼12 km, with a crust thickness of 6∼8 km. The shallow crust is a low velocity layer with sediment thickness 1∼2 km, which consists of sediment and volcanic clastic breccia produced by the magma eruption after the spreading cessation. In the spreading axis center, a low S-wave velocity zone exists at the depths of 6 km to 12 km above the Moho. We interpreted this zone as the result of partial melting of the lower crust or the presence of a magma chamber. In the same area at the depths of 17 km to 30 km, the vertical S-wave velocity gradient is negative. We interpreted it as the result of the hot magma supply moving upward in the mantle.","PeriodicalId":100242,"journal":{"name":"Chinese Journal of Geophysics","volume":"59 2","pages":"199-209"},"PeriodicalIF":0.0,"publicationDate":"2016-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/cjg2.20226","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51223575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5