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中亚造山带南部—鄂尔多斯盆地北部的壳幔结构特征及其构造意义

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地球物理学报 2024年第10期67卷 3707-3720页

作者：王玉辰滕吉文田小波陈赟中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029 中国科学院大学地球与行星科学学院北京100049 中国科学院地球科学研究院北京100029

鄂尔多斯盆地北部至中亚造山带的广大地区,经历了早前寒武纪华北克拉通的形成、古生代古亚洲洋闭合、中生代陆内造山、新生代裂陷等系列重大地质事件,且该区赋存大规模能源和矿产资源、发育河套地震带,因此该区壳幔结构特征对其地质演... 详细信息

鄂尔多斯盆地北部至中亚造山带的广大地区,经历了早前寒武纪华北克拉通的形成、古生代古亚洲洋闭合、中生代陆内造山、新生代裂陷等系列重大地质事件,且该区赋存大规模能源和矿产资源、发育河套地震带,因此该区壳幔结构特征对其地质演化过程、资源富集机制、地震孕育机理均具有重要指示意义.本文基于内蒙古满都拉—陕北延川宽频带线性地震台阵资料,开展同剖面人工源地震测深结果约束下的多频接收函数和面波频散联合反演、接收函数共转换点叠加成像研究,构建了纵跨中亚造山带南部—阴山造山带—河套地堑—鄂尔多斯盆地北部一线的地壳上地幔精细结构.研究结果显示:沿剖面Moho面存在较大起伏,深度变化范围为35~48 km,整体上呈现以河套地堑为中心,相向汇聚、分段加深的近似对称图案;河套地堑地段,Moho面以穹窿形上隆的方式完成过渡,Moho面上隆、上地幔低速区的分布范围与孔兹岩带分布之间具有较好的一致性;大青山、乌拉山、色尔腾山交汇部位的地震活动分布,在空间上呈现速度结构迥异、相对独立的花状构造特征.以上特征指示研究区地壳在古元古代鄂尔多斯—阴山地块碰撞拼合、古生代中亚造山带造山的构造格架基础上,主要记录了中生代燕山运动B幕的强烈南北向挤压变形,并叠加了新生代以来,特别是新近纪至今鄂尔多斯北缘的强烈伸展断陷作用;渐新世河套地堑的初始发育是基于古元古代鄂尔多斯—阴山地块的碰撞拼合带启动的,意味着克拉通陆核的早期结合带在后期演化中依然保持着构造薄弱带的属性;大青山山前断裂、色尔腾山山前断裂是交汇区的主干断裂,它们均具备正断和走滑性质,而乌拉山山前断裂、北缘断裂分别在两者之间起到调节作用,推测1996年包头6.4级地震的发震断层对应北部色尔腾山山前断裂东段沿南倾方向在地壳深部的延伸.

关键词：中亚造山带阴山造山带河套地堑鄂尔多斯盆地接收函数和面波频散联合反演地壳上地幔结构花状构造 1996年包头6.4级地震

Study on crustal, lithospheric and asthenospheric thickness beneath the Qinghai-Tibet Plateau and its adjacent areas

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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

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.

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.

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

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