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Receiver function imaging of dense seismic array and deep dynamic mechanism beneath the eastern South China

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Science China Earth Sciences 2023年第6期66卷 1289-1308页

作者： Rubing HAN Dinghui YANG qiusheng li Rong HUANG Hongshuang ZHANG Jiangtao li Hao CHEN Zhuo YE Wei FU Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Institute of Geophysics and Geomatics China University of GeosciencesWuhan 430074China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330001China SinoProbe Center Chinese Academy of Geological SciencesBeijing 100037China College of Transportation Engineering Nanjing Tech UniversityNanjing 211816China

The Mesozoic tectonic framework of the eastern South China is mainly controlled by subduction,turning toward,and rollback of the Pacific Plate.Recent studies of receiver function imaging and ambient noise tomography have revealed the“Yshaped”thinnest crustal belt in the eastern South China under the overall extension of the lithosphere.However,the deep dynamic environment and formation mechanisms of the thin crustal belt remain debatable.Here we obtained high-resolution images of the crustal thickness and Poisson’s ratio in the eastern South China Block applying the recently proposed H-κ-c receiver function method,using data recorded by 305 dense portable broadband stations and 219 permanent stations surrounding.Additionally,we discussed the deep dynamic formation mechanism of the“Y-shaped”thinnest crustal belt coupled with two common conversion point stacked images at key locations.Results show that the average crustal thickness of the study area is 33 km(thin crust)and the average Poisson’s ratio is 0.24(low ratio).The overall crustal thinning toward the continental margin is likely because eastern South China was in a back-arc extension environment,which was induced by the rollback of the subducted plate in the Early Cretaceous.The crustal thickness of the“Y-shaped”thinnest crustal belt isling.The eastern branch of the thin crustal zone indicates the potential location of the Pacific subduction slab breakoff,and the formation mechanism may be related to the interaction of deep-shallow processes,including the upwelling of mantle heat flow through the slab window and transtensional pre-existing faults.We developed a dynamic model that combines subduction-breakoff-rollback processes of the Paleo-Pacific Plate and accompanying deep fluid upwelling to explain the regio

关键词： Eastern South China Block Dense seismic array Receiver function “Y-shaped”thinnest crustal belt Slab breakoff

200-kg large explosive detonation facing 50-km thick crust beneath west Qinling,northeastern Tibetan plateau

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Earthquake Science 2009年第4期22卷 389-393页

作者： qiusheng li lithosphere Research Centre Institute of Geolog) Chinese Academy of Geological Sciences Beijing 100037 China Eearthprobe and Geodynamics Open Laboratory of Chinese Academy of Geological Sciences Beijing 100037 China

It is difficult to acquire deep seismic reflection profiles on land using the standard oil-industry acquisition parameters. This is especially true over much of Tibetan plateau not only because of severe topography and rapid variation of both velocity and thickness of near-surface layer, but also strong attenuation of seismic wave through the thickest crust of the Earth. Large explosive sources had been successfully detonated in US, but its application in Tibetan plateau rarely has an example of good quality. Presented herein is the data of a 200-kg single shot we recorded in west Qinling, northeastern Tibetan plateau. The shot gather data with phenomenal signal-to-noise ratios illustrate the energy of the Prop phase. Although the observations are only limited to the northeastern Tibetan plateau and thus cannot comprise an exhaustive study, they nevertheless suggest that large explosions may be a useful exploration tool in Tibetan Plateau where standard seismic sources and profiling methods fail to produce adequate data of low crust.

关键词： northeastern Tibetan plateau deep seismic reflection profile Moho, large explosive sources

Wave field in two-phase media by the convolutional differentiator method

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Earthquake Science 2011年第5期24卷 409-418页

作者： Zhuo Ye Xinfu li qiusheng li Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China School of Geophysics and Information Technology China University of Geosciences Beijing 100083 China Earthprobe and Geodynamics Open Laboratory of Chinese Academy of Geological Sciences Beijing 100037 China

This paper applies the convolutional differentiator method, based on generalized Forsyte orthogonal polynomial （CFPD）, to simulate the seismic wave propagation in two-phase media. From the numerical results we can see that three types of waves, fast P-waves, S-waves and slow P-waves, can be observed in the seismic wave field. The experiments on anisotropic models demonstrate that the wavefront is elliptic instead of circular and S-wave splitting occurs in anisotropic two-phase media. The research has confirmed that the rules of elastic wave propagation in fluid-saturated porous media are controlled by Biot＇s theory. Experiment on a layered fault model shows the wavefield generated by the interface and the fault very well, indicating the effectiveness of CFPD method on the wavefield modeling for real layered media in the Earth. This research has potential applications to the investigation of Earth＇s deep structure and oil/gas exploration.

关键词： convolutional Forsyte polynomial differentiator （CFPD） two-phase media seismicwave field numerical modeling

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劳动力转移、农业机械权属与农户生产效率

中国农机化学报 2024年第6期45卷 294-302页

作者：李秋生傅青刘小春江西农业大学经济管理学院南昌市330045

基于中国劳动力动态调查(CLDS)数据,使用随机前沿分析法测算农户生产效率,运用Tobit模型检验家庭劳动力转移对农户生产效率的影响,并进一步分析农业机械权属在两者之间的调节作用。研究发现:家庭劳动力转移对农户生产效率的制约作用显著... 详细信息

基于中国劳动力动态调查(CLDS)数据,使用随机前沿分析法测算农户生产效率,运用Tobit模型检验家庭劳动力转移对农户生产效率的影响,并进一步分析农业机械权属在两者之间的调节作用。研究发现:家庭劳动力转移对农户生产效率的制约作用显著,使用农业机械会显著提高农户生产效率,但农业机械自有比农业机械租借在缓解劳动力转移对农户生产效率不利方面更具积极作用。因此,政府应引导农民购置使用先进适用的农业机械,创新补贴资金使用与管理方式,提升农民购机用机能力。

关键词：劳动力转移农业机械权属农户生产效率随机前沿模型

Static Corrections Methods in the Processing of Deep Reflection Seismic Data

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Journal of Earth Science 2014年第2期25卷 299-308页

作者： Xiaosan Zhu Rui Gao qiusheng li Ye Guan Zhanwu Lu Haiyan Wang Institute of Geology Chinese Academy of Geological Sciences

Statics are big challenges for the processing of deep reflection seismic data. In this paper several different statics solutions have been implemented in the processing of deep reflection seismic data in South China and their corresponding results have been compared in order to find proper statics solutions. Either statics solutions based on tomographic principle or combining the low-frequency components of field statics with the high-frequency ones of refraction statics can provide reasonable statics solutions for deep reflection seismic data in South China with very rugged surface topography, and the two statics solutions can correct the statics anomalies of both long spatial wavelengths and short ones. The surface-consistent residual static corrections can serve as the good compensations to the several kinds of the first statics solutions. Proper statics solutions can improve both qualities and reso- lutions of seismic sections, especially for the reflections of Moho in the upmost mantle.

关键词： deep reflection seismic data static correction field static refraction static tomographic static residual static correction.

High-resolution 3D crustal S-wave velocity structure of the MiddleLower Yangtze River Metallogenic Belt and implications for its deep geodynamic setting

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Science China Earth Sciences 2019年第9期62卷 1361-1378页

作者： Song LUO Huajian YAO qiusheng li Weitao WANG Kesong WAN Yafeng MENG Bin liU Laboratory of Seismology and Physics of the Earth’s Interior School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China National Geophysical Observatory at Mengcheng University of Science and Technology of China Mengcheng 233500 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Institute of Geophysics Chinese Earthquake Administration Beijing 100081 China

The Middle-Lower Yangtze River Metallogenic Belt(MLYMB) is an important mineral resource region in China.High-resolution crustal models can provide crucial constraints to understand the ore-forming processes and geodynamic setting in this region. Using ambient seismic noise from 107 permanent and 82 portable stations in the MLYMB and the adjacent area,we present a new high-resolution 3D S-wave velocity model of this region. We first extract 5–50 s Rayleigh wave phase velocity dispersion data by calculating ambient noise cross-correlation functions(CFs) and then use the surface wave direct inversion method to invert the mixed path travel times for the 3D S-wave velocity structure. Checkerboard tests show that the horizontal resolution of the 3D S-wave velocity model is approximately 0.5°–1.0° and that the vertical resolution decreases with increasing noise and depth. Our high-resolution 3D S-wave velocity model reveals:(1) AV-shaped high-velocity zone(HVZ) is located in the lower crust and the uppermost mantle in the study region. The western branch of the HVZ passes through the Jianghan Basin,the Qinling-Dabie orogenic belt and the Nanxiang Basin. The eastern branch, which almost completely covers the main body of the MLYMB, is located near the Tanlu Fault. The low-velocity anomalies between the western and eastern branches are located in the area of the Qinling-Dabie orogenic belt.(2) High-velocity uplifts(HVUs) are common in the crust of the MLYMB,especially in the areas near the Tanlu Fault, the Changjiang Fault and the Yangxin-Changzhou Fault. The intensities of the HVUs gradually weaken from west to east. The V-shaped HVZ in the lower crust and uppermost mantle and the HVUs in the middle and lower crust likely represent cooled mantle intrusive rocks. During the Yanshanian period, fault systems formed in the MLYMB due to the convergence between the South China Plate and the North China Plate, the multiple-direction drifting of the PaleoPacific Plate and its subduction beneath the Eurasian Plate. The dehydrati

关键词： Middle-Lower Yangtze River Metallogenic Belt Ambient noise Surface wave Crustal structure Mineralization dynamics

真菌病毒BmPV1抑制Bipolaris maydis侵染寄主作用研究

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菌物学报 2024年第6期43卷 96-104页

作者：王亚娇及增发栗秋生吴玉星韩森孔令晓河北省农林科学院植物保护研究所、农业农村部华北北部作物有害生物综合治理重点实验室、河北省农业有害生物综合防治技术创新中心、河北省作物有害生物综合防治国际科技联合研究中心河北保定071000 河北省农林科学院河北石家庄050000

玉米小斑病是我国玉米生产上的重要病害之一,每年造成玉米大幅减产。Bipolarismaydis partitivirus 1(BmPV1)病毒是玉米小斑病菌B.maydis携带的一种dsRNA病毒,具有弱毒性,能够引起B.maydis的致病力降低,但BmPV1对寄主侵染的影响并不明... 详细信息

玉米小斑病是我国玉米生产上的重要病害之一,每年造成玉米大幅减产。Bipolarismaydis partitivirus 1(BmPV1)病毒是玉米小斑病菌B.maydis携带的一种dsRNA病毒,具有弱毒性,能够引起B.maydis的致病力降低,但BmPV1对寄主侵染的影响并不明确。本研究采用农杆菌转化法将gfp基因分别导入到携带BmPV1病毒的玉米小斑病菌株3086-BmPV1以及脱毒菌株3086-non中,通过PCR扩增及荧光观察分析荧光标记菌株的稳定性;检测gfp基因的插入对菌株生物学特征的影响;采用叶面喷施孢子悬浮液的方式接种,并利用共聚焦显微镜观察带毒菌株及脱毒菌株对玉米叶片的侵染情况。PCR扩增和荧光观察结果表明,gfp基因成功整合到菌株3086-BmPV1和3086-non中;生物学特征分析表明gfp基因的插入对菌株的生长速度、产孢量和致病力无显著影响;侵染观察发现脱毒菌株3086-non-GFP对玉米叶片侵染有两条途径:直接侵染玉米表皮细胞并向邻近细胞扩散;侵染气孔,并通过气孔沿着细胞间隙向邻近细胞扩散。带毒菌株3086-BmPV1-GFP只能在叶片表面生长,多数不能侵染表皮细胞。综上所述,本研究观察了玉米小斑病菌带毒和不带毒菌株对玉米的侵染过程,明确了病毒BmPV1能够通过抑制小斑病菌对玉米叶片的侵入达到弱毒作用。

关键词：玉米小斑病真菌病毒BmPV1 弱毒性荧光标记侵染过程

红色金融史融入财经类高校思政课的价值取向与路径探析

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金融理论与教学 2024年第3期42卷 102-107页

作者：李秋生陈星河北金融学院马克思主义学院河北保定071002

红色金融史中蕴含着丰富的知识元素、能力元素、价值元素,将其融入财经类高校思政课教学中,能够拓展财经类高校思政课的教育资源、思政课教师的教学针对性。从财经类高校学生的专业特点及学科属性出发,将红色金融史融入财经类高校思政... 详细信息

红色金融史中蕴含着丰富的知识元素、能力元素、价值元素,将其融入财经类高校思政课教学中,能够拓展财经类高校思政课的教育资源、思政课教师的教学针对性。从财经类高校学生的专业特点及学科属性出发,将红色金融史融入财经类高校思政课课堂,可以培养未来金融行业从业者的职业操守、职业素养、职业道德及爱岗敬业精神,增强他们的社会责任感和担当意识。红色金融史融入财经类高校思政课是发挥党史思政育人功效的重要路径,也是财经类高校育人育才的内在要求。在融入实践中,要处理好“融入什么”“为什么融入”“怎么融入”“融入评价”四个方面的关系,从而增强红色金融史融入财经类高校思政课的实效性,更好地落实立德树人的根本任务。

关键词：红色金融史思政课价值取向路径探析

The thickness and structural characteristics of the crust across Tibetan plateau from active-sources seismic profiles

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Earthquake Science 2009年第1期22卷 21-31页

作者： qiusheng li Rui Gao Zhanwu Lu Ye Guan Jisheng Zhang Pengwu li Haiyan Wang Rizheng He Marianne Karplus lithosphere Research Center Institute of Geology Chinese Academy of Geology ScienceBeijing 100037 China Earthprobe and Geodynamics Open Laboratory of Chinese Academy of Geology Science Beijing 100037 China Crustal Geophysics Group Stanford University Stanford CA 94305 USA

The Tibetan plateau as one of the youngest orogen on the Earth was considered as the result of continent-continent collision between the Eurasian and Indian plates. The thickness and structure of the crust beneath Tibetan plateau is essential to understand deformation behavior of the plateau. Active-source seismic profiling is most available geophysical method for imaging the structure of the continental crust. The results from more than 25 active-sources seismic profiles carried out in the past twenty years were reviewed in this article. A preliminary cross crustal pattern of the Tibetan Plateau was presented and discussed. The Moho discontinuity buries at the range of 60-80 km on average and have steep ramps located roughly beneath the sutures that are compatible with the successive stacking/accretion of the former Cenozoic blocks northeastward. The deepest Moho （near 80 km） appears closely near IYS and the crustal scale thrust system beneath southern margin of Tibetan plateau suggests strong dependence on collision and non-distributed deformation there. However, the -20 km order of Moho offsets hardly reappears in the inline section across northern Tibetan plateau. Without a universally accepted, convincing dynamic explanation model accommodated the all of the facts seen in controlled seismic sections, but vertical thickening and northeastern shorten of the crust is quite evident and interpretable to a certain extent as the result of continent-continent collision. Simultaneously, weak geophysical signature of the BNS suggests that convergence has been accommodated perhaps partially through pure-shear thickening accompanied by removal of lower crustal material by lateral escape. Recent years the result of Moho with -7 km offset and long extend in south-dip angle beneath the east Kunlun orogen and a grand thrust fault at the northern margin of Qilian orogen has attract more attention to action from the northern blocks. The broad lower-velocity area in the upper-middle crust of the Lhasa block was once considered

关键词： crustal structure crustal thickness active-sources seismic Tibetan plateau