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STRUCTURES OF CRUST AND UPPER MANTLE AND THEIR RELATION TO CENOZOIC TECTONISM IN NORTHERN PART OF NORTH CHINA

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Science China Chemistry 1983年第5期26卷 550-560页

作者：刘国栋刘昌铨 Beijing Zhengzhou State Seismological Bureau geophysical Prospecting brigade Institute of Geology

On the basis of deep seismic profiling carried out in the past six years, the velocity, gcoelectrical and geothermal structures of the crust and upper mantle and tectonic frames of the Moho discontinuity and asthenosphere have been determined for the northern part of North China. A close relationship exists between Cenozoic teetonism and the geodynamic processes in the crust and upper mantle. We surmise that the intense inhomogeneous activities of the asthenospherc between the late Cretaceous and the Cenozoic may have given rise to the following processes: lithospheric breakup, basalt eruptions, increase in geothermal gradient, lower crustal creep, upper crustal spreading, subsidence and the accumulation of sedimentary deposits as well as the development of shallow-level normal faults. The dip angles of such faults gradually decrease with depth and thus disappear in the low velocity layer of the crust.

关键词： STRUCTURES OF CRUST AND UPPER MANTLE AND THEIR RELATION TO CENOZOIC TECTONISM IN NORTHERN PART OF NORTH CHINA than NNE

Characteristic　of　crustal　structure　in　the　Shulu　fault　basin　and　its　vicinity

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Acta Seismologica Sinica(English Edition) 1994年第4期7卷 587-594页

作者：王椿镛张先康林中洋李学清 Institute of Geophysics State Seismological Bureau Beijing China geophysical Prospecting brigade State Seismological Bureau Zhengzhou China

The deep seismic reflection profiling carried out in Xingtai earthquake area provides a new knowledge of the crustal structure of the Shulu fault basin and its vicinity. In the Ningjin-Xinhe and Lincheng-Julu deep seismic reflection profiles trending in NWW, CDP stack profiles respectively show a one-side fault basin (i. e. Shulu fault basin) within TWT 4. 0s. The width of the basin is about 15 km (Eogene system boundary), and Xinhe fault extends to below TWT 4. 0s (i. e. 8 km deep) with listric shape as a main boundary fault. These profiles also display distinctly a detachment in mid-crust. The Xinhe fault extends downward and converges to the detachment. The results of deep seismic sounding and magnetotelluric sounding indicate the low-velocity and highconductive zone beneath the detachment, which is beneficial to the detach between upper and lower plates. The Renxian-Ningjin deep seismic reflection profile trending in NNE lies within the fault basin, which shows the complicated structure of the basin. The shallow part of the profile is divided into three sub-basins by three lateral uplifts. In the mid-lower crust from Gengzhuangqiao to Xiaohezhuang of the profile, there are a lot of strong reflection events with laminae structure, which have been deformed strongly. Two NWW-trending profiles also have similar reflection feature. This may indicate that there is a relative large region where the magma upwell into mid-lower crust. The abnormal low velocity zone in lower crust indicates that the magmatism is still strong at present. The magmatism may be an important factor of the tectonic active region.

关键词： crustal structure deep seismic reflection profile CDP stack detachment magmatism

STUDY ON CRUSTAL THICKNESS IN TAIWAN REGION——PRELIMINARY RESULTS BY 3D GRAVITY INVERSION

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Chinese Science Bulletin 1991年第11期36卷 928-931页

作者：刘光夏赵文俊吴岫云任文菊 geophysical Prospecting brigade State Seismological Bureau Zhengzhou 450003 PRC Seismological Bureau of Hainan Province Haikou 570003PRC

Bouguer anomaly can be considered as the total sum of the attraction effects resulting from the geological bodies beneath the observational point with different scales, densities and depths. How can we extract tlae information of deep crust from Bouguer anomaly?The authors suggested using the formula of 3D positive calculation to determine the surface gravity anomaly caused by the shallow strata. After layering forward calculation, the deep residual gravity anomaly reflecting crustal structure is obtained. If we take Moho depth of 3 l km from DSS in Fujian Province as a controlling point, the crustal thickness throughout the whole region is inversed. As for the calculation and error, see Refs.

关键词： 3D gravity inversion crustal thickness.

The Basic Structure of Dabie Collisional Orogen

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Chinese Science Bulletin 1993年第22期38卷 1884-1888页

作者：董树文孙先如张勇黄德志王刚戴世坤于邦存 Anhui Institute of Geological Sciences Hefei 230001 PRC Group No. 107 of First geophysical Prospecting brigade of MGMR Bengbu 233000 PRC

The continental dynamic research has focused on the theory and model of collisional orogenic belts. As the joining zone between the southern and northern China massives, Dabie orogen has attracted many geologists from China and abroad, for its various distinctions, especially the exposed root profile, which rarely occurs in the world, of the orogenic belt. At present, however, the collision process, structure and deep geology of the orogen are not well known. The magnetotelluric prospecting profile from Lu’an,

关键词： collisional orogen crust structure magnetotelluric prospecting Dabie Mountains

Application of geophysical methods in fine detection of urban concealed karst:A case study of Wuhan City,China

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China Geology 2024年第3期7卷 517-532页

作者： Dao-han Liu Lei Wang Lei Liu Jun-jie Xu Jian-qiang Wu Pan Liu Wuhan Center China Geological SurveyWuhan430205China Central South China Center for Geoscience Innovation Wuhan430205China geophysical Exploration brigade of Hubei Geological Bureau Wuhan 430056China

The construction of modern livable cities faces challenges in karst areas,including ground collapse and engineering ***,with a population of 13.74×10^(6) and approximately 1161 km^(2)of soluble rocks in the urban area of 8569.15 km^(2),predominantly consists of concealed karst areas where occasional ground collapse events occur,posing significant threats to underground engineering *** address these challenges,a comprehensive geological survey was conducted in Wuhan,focusing on major karstrelated *** methods offer advantages over drilling in detecting concealed karst areas due to their efficiency,non-destructiveness,and *** paper reviewed the karst geological characteristics in Wuhan and the geophysical exploration methods for karst,selected eight effective geophysical methods for field experimentation,evaluated their suitability,and proposed method combinations for different karst *** results show that different geophysical methods have varying applicability for karst detection in Wuhan,and combining multiple methods enhances detection *** specific recommendations for method combinations provided in this study serve as a valuable reference for karst detection in Wuhan.

关键词： Ground Penetrating Radar(GPR) Electric Resistivity Tomography(ERT) Opposing-coils Transient Electromagnetic Method(OCTEM) Microtremor Array Measurements(MAM) Multi-channel Analysis of surface wave(MASW) Multi-source surface wave exploration(MSSW) Electromagnetic wave CT(EM CT) Surface Nuclear Magnetic Resonance(SNMR) Concealed karst Urban geological survey engineering

A COMPREHENSIVE STUDY ON LITHOSPHERIC STRUCTURE IN NORTH CHINA

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Chinese Science Bulletin 1988年第21期33卷 1803-1807页

作者：冯锐郑书真 Institute of Geophysics State Seismological Bureau Beijing geophysical Exploration brigade State Seismological Burcau Zhengzhou

In the last three years a vast amount of new geological and geophysical data have been collected and processed in our study. Then a strict three-dimensional gravitational computation combined with seismic data has bee... 详细信息

关键词： lithospheric structure gravitational inversion North China

Denoising of seismic data via multi-scale ridgelet transform

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Earthquake Science 2009年第5期22卷 493-498页

作者： Henglei Zhang Tianyou Liu Yuncui Zhang Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China Key Laboratory of Tectonics andPetroleum Resources (China University of Geosciences) Ministry of Education Wuhan 430074 China The 5th geophysical Prospecting brigade Zhongnan Petroleum Bureau Xiangtan 411104 China

Noise has traditionally been suppressed or eliminated in seismic data sets by the use of Fourier filters and, to a lesser degree, nonlinear statistical filters. Although these methods are quite useful under specific conditions, they may produce undesirable effects for the low signal to noise ratio data. In this paper, a new method, multi-scale ridgelet transform, is used in the light of the theory of ridgelet transform. We employ wavelet transform to do sub-band decomposition for the signals and then use non-linear thresholding in ridgelet domain for every block. In other words, it is based on the idea of partition, at sufficiently fine scale, a curving singularity looks straight, and so ridgelet transform can work well in such cases. Applications on both synthetic data and actual seismic data from Sichuan basin, South China, show that the new method eliminates the noise portion of the signal more efficiently and retains a greater amount of geologic data than other methods, the quality and consecutiveness of seismic event are improved obviously as well as the quality of section is improved.

关键词： ridgelet transform multi-scale random noise sub-band decomposition complex Morlet wavelet

Deep seismic reflection profiling revealing the complex crustal structure of the Tongling ore district

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Science China Earth Sciences 2004年第3期47卷 193-200页

作者： L5 Qingtian1, HOU Zengqian1, ZHAO Jinhua1, SHI Danian1, WU Xuanzhi1, CHANG Yinfo1, PEI Rongfu1,HUANG Dongding2 & KUANG Chaoyang2 1. Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, China 2. The Sixth geophysical Exploration brigade, Petroleum Bureau of East China, Nanjing 210009, China Institute of Mineral Resources Chinese Academy of Geological Sci. Beijing 100037 China The Sixth Geophys. Explor. brigade Petroleum Bureau of East China Nanjing 210009 China

The deep seismic profiling across the Tongling ore district reveals a complex crustal structure. Strong contrasting dipping layered reflections (4—11 s, TWT),which dominate the lower crust of the northern part of the profile, are interpreted as the underplating of the basalt related to extensional tectonism. In the south of the profile, the Yangtze craton is characterized by strong reflections in the middle crust, showing a distinct two-layer crustal structure. Over the region of the Tongling uplift, there appear the complex arc shape reflections, suggesting folded, faulted and intruded structures, and the transparent zone below them reveals the existence of batholith. The south dipping strong reflections between the upper crust and lower crust (4—7 s, TWT) suggest a detachment between them. The detachment provided space for the magma intrusion, and caused the formation of the batholith. The Yangtze craton has a clear Moho re-flection, while the Tongling uplift has a weak Moho, whereas below the reflective lower crust in the northern part of the profile, there are sub-Moho reflections. The abrupt variation of the Moho characteristics within a short distance indicates the complexity of magmatic activity.

关键词： metallogenic belt, ore district, deep seismic profiling, crustal structure.

HEAT FLOW MEASUREMENTS IN PANZHIHUA-XICHANG(PANXI) PALEORIFT ZONE, SW CHINA

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Chinese Science Bulletin 1987年第8期32卷 550-554页

作者：汪集暘汪缉安黄少鹏张文仁周友松金昕 Institute of Geology Academia Sinica Beijing geophysical brigade Panxi Geological Team of Sichuan Geological Bureau Xichang geophysical brigade Panxi Geological Team of Sichuan Geological Bureau Xichangeat flow measurements are of great significance in rift studies. The Panxi area has. been considered to be a paleorift zone of the Hercynian-Indosinian period. For a long time the geological and geophysical community are greatly concerned about the thermal state and the possibility of the existence of high heat flow in this region. And great efforts and research work have been made by joint geothermal study program of Geother

Heat flow measurements are of great significance in rift studies. The Panxi area has. been considered to be a paleorift zone of the Hercynian-Indosinian period. For a long time, the geological and geophysical community are greatly concerned about the thermal state and the possibility of the existence of high heat flow in this region. And great efforts and research work have been made by joint geothermal study program of

关键词： concerned geophysical possibility strata PALEORIFT ZONE PANXI SW CHINA mudstone Paleozoic rock