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Chinese Science Bulletin 2007年第6期52卷 797-804页

作者： ZHANG XueMei SUN RuoMei teng jiwen Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China College of Geo-exploration Science and Technology Jilin University Changchun 130026 China

Based on the results of pure dispersions of Rayleigh wave tomography in the Qinghai-Tibet Plateau and its adjacent areas, taking S wave velocities from previous linear inversion as the initial model, us-ing the simulated annealing algorithm, a nonlinear simultaneous inversion has been carried out for S wave velocity and thickness of different layers, including the crust, the lithosphere and the astheno-sphere. The results indicate: The crustal thickness shows strong correlation with geology structures sketched by the sutures and major faults. The crust is very thick in the Qinghai-Tibet Plateau, varying from 60 km to 80 km. The lithospheric thickness in the Qinghai-Tibet Plateau is thinner (130―160 km) than its adjacent areas. And two blocks can be recognized, divided by an NNE strike boundary running between 90°E―92°E inside the plateau. Its asthenosphere is relatively thick, varies from 150 km to 230 km, and the thickest area is located in the western Qiangtang. India has a thinner crust (32―38 km), a thicker lithosphere of 190 km and a rather thin asthenosphere of only 60 km. Sichuan and Tarim basins have the crust thickness less than 50 km. Their lithospheres are thicker than the Qinghai-Tibet Plateau, and their asthenospheres are thinner. A discussion has been made on the character and formation mechanism of the typical crust-mantle transition zone in the western Qiangtang block.

关键词：青藏高原邻近地区地壳厚度岩石圈厚度岩流圈厚度

The 3-D structure of shear wave in South China and the southward extension of Tanlu fault

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Chinese Science Bulletin 2001年第4期46卷 284-289页

作者： teng jiwen WANG Guangjie ZHANG Zhongjie HU Jiafu Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100101China Yunnan University Kunming 650091China

By processing the CSND Rayleigh wave data with the matched filter FTAN technique, Rayleigh wave dispersion for southeast China is obtained. The 4°×4°S wave dispersion of the pure path is calculated using random inversion scheme, and 3-D S wave velocity structure is set up. Incorporating the above-mentioned results with wide angle seismic sounding data, we studied structure framework and the extending of faults in this area, which demonstrates that the depth of Moho in South China varies from 30 to 40 km, shallower from west to east. The depth of Moho varies from 25 to 28 km for the offshore. The depth of the asthenosphere in upper mantle varies from 60 to 100 km. The depth difference of layers at the two sides of Tanlu fault is more than 10 km at the south part of the Yangtze River, and the fault extends downward more than 170 km. The fault exceeds the main land at Hainan Island and slips into the southern China Sea. Both Tanlu fault and the huge bend of gravity gradient anomaly are influenced by

关键词： seismic surface wave Moho mantle cover layer as-thenosphere 3-D velocity structure Tanlu fault.

Deep Mechanical Background for the Cenozoic Volcanism in the Tibetan Plateau

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Journal of China University of Geosciences 2005年第4期16卷 334-339页

作者： Xiong Xiong Wang Jiye teng jiwen Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Institute of Geology and Geophysics Chinese Academy of Sciences Beij ing 100101 China Graduate School Chinese Academy of Sciences Beijing 100038 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100101 China

The principle prerequisite for the formation of a volcano is the generation of a channel for magma transportation. There is little research on the deep mechanical mechanism for the formation of a magma transportation channel in the Tibetan plateau. Based on the subcrustal mantle convectiongenerated stress field inversed by gravity anomalies, together with its relationship to the Cenozoic volcanism in the plateau, and the mechanism of crustal fracture formation, as well as the numerical results of the evolution of mantle convection beneath the plateau, this paper investigates the deep mechanical mechanism for the formation of a magma transportation channel in the Tibetan plateau. There are two significant extensional convection-generated stress zones beneath the plateau, in which the volcanic rocks in the central and northern parts of the plateau are distributed. The Linzizong volcanism in southern Tibet correlates the upwelling mantle flow prior to the India-Asia collision or during the early stage of the collision. The magnitude of the stress is - 100 MPa, which is the same order of force that causes crustal fractures. The evidence implies that the mantle convection-generated stress is one of the principle causes of crustal fractures, and furthermore, the formation of the magma transportation channel in the Tibetan plateau.

关键词： mantle convection stress field Tibetan plateau volcanism magma channel.

Some important scientific problems in current lithospheric physics research in China

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Applied Geophysics 2007年第1期4卷 66-72页

作者： teng jiwen The Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Jilin University Changchun 130026 China

China has achieved much during recent years in the area of lithospheric physics research and promoted the development of the geosciences （teng, 2004）. However, in the 21^st century, national needs and policy challenges the science of lithospheric physics. I suggest a general analysis, research, and development direction for lithospheric physics and point out clearly the content, core problems, and key scientific problems in this field. The realization of the earth and the discovery of the basic mechanisms of mountains, basins, minerals, and natural disasters depend basically on high-resolution observations of geophysics, the delineation of the fine structure of crust and mantle （2D and 3D） inside the lithosphere, substance and energy exchanges in the deep earth, the process of deep physical, mechanical, and chemical actions, and deep dynamical response. Therefore, geophysics should be the pioneer in the geosciences field in the first half of the 21^st century. I end with an analysis and discussion of some problems and difficulties in the research of lithospheric physics.

关键词： Physics of the lithosphere exchanges of deep substance and energy resources energy and disaster pioneer function and deep dynamical process.

Crustal wide-angle reflection imaging along Lianxian-Gangkou profile in Guangdong province,China

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Earthquake Science 2009年第4期22卷 357-363页

作者： Zhongjie Zhang Bing Zhao Xi Zhang jiwen teng State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

A 400 km-long wide-angle seismic experiment along Lianxian-Gangkou profile in South China was carried out to study contact relationship between southeast continental margin of Yangtze block and northwest continental margin of Cathaysia block. We reconstructed crustal wide-angle reflection structure by the depth-domain pre-stack migration and the crustal velocity model constructed from the traveltime fitting. The wide-angle reflection section shows different reflection （from crystalline basement and Moho） pattern beneath the Yangtze and Cathaysia blocks, and suggests the Wuchuan-Sihui fault is the boundary between them. A cluster of well-developed reflections on Moho and in its underlying topmost mantle probably comes from alternative thin layers, which may be seismic signature of strong interaction between crust and mantle in the tectonic environment of lithosphere extension.

关键词： Yangtze block Cathaysia block seismic sounding seismic wide-angle reflection Moho reflection clustering crust/mantle interaction

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高精度地球物理学是创新未来的必然发展轨迹

地球物理学报 2021年第4期64卷 1131-1144页

作者：滕吉文中国科学院地质与地球物理研究所北京100029 中国科学院大学北京100049 吉林大学长春100044

地球物理学在整个地球科学研究与探索中占有重要地位,突破该领域以描述、推断为主体的框架,并逐步向量化或半量化前进确为必然.地球物理学逐步向高精度升华乃深化理解各有关科学问题的时代需求.基于物理学概念,从定义出发促使多学科交... 详细信息

地球物理学在整个地球科学研究与探索中占有重要地位,突破该领域以描述、推断为主体的框架,并逐步向量化或半量化前进确为必然.地球物理学逐步向高精度升华乃深化理解各有关科学问题的时代需求.基于物理学概念,从定义出发促使多学科交叉和不断创新,是地球物理学能否抢占地球科学制高点的核心所在.为此,真正意义上的高精度观测、高分辨率的数据采集和精细结构的刻画构成了高精度地球物理学的基石,是深化理解地球科学中有关壳幔形成、演化问题的深层次的内核.本文通过较系统地分析和研究提出,(1)地球科学研究进程中的定性描述和依据于浅表层过程与现象的推断有待突破;(2)夯实与把握基础科学理论是高精度地球物理学捕获真谛的“钥匙”;(3)高精度地球物理学是深化认识地球本体和逼近彼岸的基石.

关键词：高精度地球物理学多学科交叉科学理念科学真谛发展轨迹

An efficient source wavefield reconstruction scheme using single boundary layer values for the spectral element method

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Earth and Planetary Physics 2019年第4期3卷 342-357页

作者： YouShan Liu Tao Xu YangHua Wang jiwen teng José Badal HaiQiang Lan State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China Department of Earth Science and Engineering Imperial College London SW7 2AZ UK Physics of the Earth Sciences-B University of Zaragoza Pedro Cerbuna 12 50009 Zaragoza Spain

In the adjoint-state method, the forward-propagated source wavefield and the backward-propagated receiver wavefield must be available simultaneously either for seismic imaging in migration or for gradient calculation in inversion. A feasible way to avoid the excessive storage demand is to reconstruct the source wavefield backward in time by storing the entire history of the wavefield in perfectly matched layers. In this paper, we make full use of the elementwise global property of the Laplace operator of the spectral element method (SEM) and propose an efficient source wavefield reconstruction method at the cost of storing the wavefield history only at single boundary layer nodes. Numerical experiments indicate that the accuracy of the proposed method is identical to that of the conventional method and is independent of the order of the Lagrange polynomials, the element type, and the temporal discretization method. In contrast, the memory-saving ratios of the conventional method versus our method is at least N when using either quadrilateral or hexahedron elements, respectively, where N is the order of the Lagrange polynomials used in the SEM. A higher memorysaving ratio is achieved with triangular elements versus quadrilaterals. The new method is applied to reverse time migration by considering the Marmousi model as a benchmark. Numerical results demonstrate that the method is able to provide the same result as the conventional method but with about 1/25 times lower storage demand. With the proposed wavefield reconstruction method, the storage demand is dramatically reduced;therefore, in-core memory storage is feasible even for large-scale three-dimensional adjoint inversion problems.

关键词： spectral element method source wavefield reconstruction single boundary layer memory-saving ratio adjoint method reverse time migration

ABNORMAL GEOMAGNETIC FIELD RESPONSE AT INTRAPLATE TECTONIC BOUNDARY IN CONTINENT AND CONTINENTAL MARGIN IN SOUTHEASTERN CHINA

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Geotectonica et Metallogenia 2004年第2期28卷 93-117页

作者： teng jiwen YAN Yafen Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

We used matched filter, spectrum analysis, and continuation methods of potential field for data processing and obtained the geomagnetic field distribution about the continent and continental margin in southeast China. On the basis of grid data, inversion was conducted and magnetic field distribution and magnetic structure on bedding of different depths were obtained. The new results show that: 1. The magnetic field characteristics are largely different in horizontal and vertical directions and they can be divided into zones according to the continental blocks of Yangtze, Cathaysia, Kangdian (Sichuan-Yunnan) and Qinling-Dabie. 2. The Tanlu fault extends southward along the Ganjiang fault and the Wuchuan-Sihui fault after it crossed over the Yangtze River and was offset locally in the east-west direction. The Tanlu fault finally slips into the South China Sea at Hainan Island. 3. The boundary between Yangtze and Cathaysia blocks starts from Hangzhou Bay in the east, extends along Jiangshao fault and passes through Nanchang, Changsha, and Guilin, and finally enters the sea at Qinzhou, Guangxi. 4. The distribution of buried structure zone is located at 24.5°-26° N.

关键词： geomagnetic field landmass effect of boundary field deep process intraplate tectonic zone

Observation and research of deep underground multi-physical fields—Huainan–848 m deep experiment

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Science China Earth Sciences 2023年第1期66卷 54-70页

作者： Yun WANG Yaxin YANG Heping SUN Chengliang XIE Qisheng ZHANG Xiaoming CUI Chang CHEN Yongsheng HE Qiangqiang MIAO Chaomin MU Lianghui GUO jiwen teng School of Geophysics and Information Technology China University of GeosciencesBeijing 100083China School of Geophysics and Measurement-control Technology East China University of TechnologyNanchang 330013China Innovation Academy for Precision Measurement Science and Technology Chinese Academy of SciencesWuhan 430077China Institution of Engineering Protection IDEAMSPLALuoyang 471023China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081China

Compared with the surface,the deep environment has the advantages of allowing“super-quiet and ultra-clean”-geophysical field observation with low vibration noise and little electromagnetic interference,which are conducive to the realization of long-term and high-precision observation of multi-physical fields,thus enabling the solution of a series of geoscience *** the Panyidong Coal Mine,where there are extensive underground tunnels at the depth of 848 m below sea level,we carried out the first deep-underground geophysical observations,including radioactivity,gravity,magnetic,magnetotelluric,background vibration and six-component seismic *** concluded from these measurements that(1)the background of deep subsurface gravity noise in the long-period frequency band less than 2 Hz is nearly two orders of magnitude weaker than that in the surface observation environment;(2)the underground electric field is obviously weaker than the surface electric field,and the relatively high frequency of the underground field,greater than 1 Hz,is more than two orders of magnitude weaker than that of the surface electric field;the east-west magnetic field underground is approximately the same as that at the surface;the relatively high-frequency north-south magnetic field underground,below 10 Hz,is at least one order of magnitude lower than that at the surface,showing that the underground has a clean electromagnetic environment;(3)in addition to the highfrequency and single-frequency noises introduced by underground human activities,the deep underground space has a significantly lower background vibration noise than the surface,which is very beneficial to the detection of weak earthquake and gravity signals;and(4)the underground roadway support system built with ferromagnetic material interferes the geomagnetic *** also found that for deep observation in the“ultra-quiet and ultra-clean”environment,the existing geophysical equipment and observation technology hav

关键词： Multi-physical fields Radioactivity Gravity Geomagnetic Electromagnetic Earthquake Observations deep underground

Seismic traveltime inversion of 3D velocity model with triangulated interfaces

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Earthquake Science 2014年第2期27卷 127-136页

作者： Fei Li Tao Xu Minghui Zhang Zhenbo Wu Chenglong Wu Zhongjie Zhang jiwen teng State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences

Seismic traveltime tomographic inversion has played an important role in detecting the internal structure of the solid earth. We use a set of blocks to approximate geologically complex media that cannot be well described by layered models or cells. The geological body is described as an aggregate of arbitrarily shaped blocks,which are separated by triangulated interfaces. We can describe the media as homogenous or heterogeneous in each block. We define the velocities at the given rectangle grid points for each block,and the heterogeneous velocities in each block can be calculated by a linear interpolation algorithm. The parameters of the velocity grid positions are independent of the model parameterization,which is advantageous in the joint inversion of the velocities and the node depths of an interface. We implement a segmentally iterative ray tracer to calculate traveltimes in the 3D heterogeneous block *** damped least squares method is employed in seismic traveltime inversion,which includes the partial derivatives of traveltime with respect to the depths of nodes in the triangulated interfaces and velocities defined in rectangular grids. The numerical tests indicate that the node depths of a triangulated interface and homogeneous velocity distributions can be well inverted in a stratified model.

关键词： Traveltime inversion 3D Triangulated interface Block modeling