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Velocity　structure　of　the　crust　and　upper　mantle　in　Xingtai　earthquake　region　and　its　adjacent　area

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Acta Seismologica Sinica(English Edition) 1995年第3期8卷 405-412页

作者：祝治平张称康盖玉杰张建狮聂文英石金虎张成科阮红 geophysical prospecting Brigade State Seismological Bureau Zhengzhou China

Two seismic refraction profiles which are perpendicular to each other, running through Xingtai earthquake region,reveal the anomalous variations of crust-mantle velocity structure and deep tectonics. Pg wave attenuatesrapidly with distance in the earthquake region. A group of strong reflections from a depth of 21. 0 km can be identified along the section from Longyao to the piedmont of Taihang Mountain, but P. waves characterized generally by strong amplitude are not obvious. Under the earthquake region and its western neighboring region, thecrustal velocity structure features high and low velocities changed alternatively. From North China plain toShanxi plateau, the velocity at the top of the upper mantle decreases progressively, while crustal thickness increases by 11 km. Moho uplifts locally in the earthquake region. The crustal fault stretching deeply to Moho andthe discontinuous sections of Moho in the earthquake region are supposed to be the channels and zones for magmatic intrusion. The uplifting of upper mantle and magmatic intrusion are responsible for the formation ofanomalous crust-mantle structures and extending basins, and for the occurrence of Xingtai earthquake as well.

关键词： velocity structure lower crust upper crust upper mantle refraction

True Amplitude Extraction Technology and Its Application in Pre-Stack Seismic Data

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Journal of Earth Science 2015年第4期26卷 522-529页

作者： Xiaohui Yang Siyuan Cao Dian Yuan CNPC Key Laboratory of geophysical prospecting China University of Petroleum

Common-reflection-point （CRP） gather is a bridge that connects seismic data and petro- physical parameters. Pre-stack attributes extraction and pre-stack inversion, both of them are impor- tant means of reservoir prediction. Quality of CRP gather usually has great impact on the accuracy of seismic exploration. Therefore, pre-stack CRP gathers noise suppression technology becomes a major research direction. Based on the vector decomposition principle, here we propose a method to suppress noise. This method estimates optimal unit vectors by searching in various directions and then sup- presses noise through vector angle smoothing and restriction. Model tests indicate that the proposed method can separate effective signal from noise very well and suppress random noise effectively in single wavenumber case. Application of our method to real data shows that the method can recover effective signal with good amplitude preserved from pre-stack noisy seismic data even in the case of low signal to noise ratio （SNR）.

关键词： vector decomposition noise suppression angle smooth spline function.

Shift sampling theory of Fourier transform computation

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Science China(Technological Sciences) 1997年第1期40卷 21-27页

作者：柴玉璞 Bureau of geophysical prospecting China Oil Corporation Gucheng 072659 China

The DFT transform us extended to DFTξη transform and the relationship between FT and DFTξη is given by the Fourier transform discretization theorem. Based on the theorem, the DFTξη algorithm-error equation (DFTξη A-E equation) is established, and the minimization property of discrete effect and the oscillation property of truncation effect are demonstrated. All these construct the shift sampling theory——a new theory about Fourier transform computation.

关键词： Fourier transform shift sampling theory DFTξη A-E equation discrete effect minimization truncation effect oscillation.

Structural Styles of Fronts of Thrust-Detachment Faults in Petroleum-bearing Areas of Western China

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Acta Geologica Sinica(English Edition) 1999年第4期73卷 371-383页

作者： Wang Tonghe Institute of Geology Bureau of Oil Geophysical ProspectingHebei 072750

The front of a thrust-detachment fault may have various styles such as decoupling, fold, forethrust and backthrust ones because of differences in magnitude, direction and time of the forces exerted on the fault and the inhomogeneity of rock mechanical properties. They have different characteristics and are usually associated with gravity structure, inverse structure and diapir structure. These structures exist together in the same thrust-detachment fault and can influence, compensate for and convert into each other. They provide important grounds not only for the study of the dynamic state, propagation mode, evolutionary process and formation mechanism but also for the analysis of the petroleum generation, migration, accumulation and preservation and arrangement of drill holes in foreland basins.

关键词： structural style front thrust-detachment fault petroleum-bearing areas of western China

Sequence architecture and sedimentary characteristics of a Middle Jurassic incised valley,western Sichuan depression,China

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Petroleum Science 2018年第2期15卷 230-251页

作者： Jun-Long Liu Wei Yin You-Liang Ji Tian-Yun Wang Fu-Xiang Huang Hai-Yue Yu Wen-Shu Li Sinopec Exploration&Production Research Institute Beijing 100083China State Key Laboratory of Petroleum Resources and prospecting China University of PetroleumBeijing 102249China Xinxing geophysical Department Bureau of Geophysical ProspectingCNPCZhuozhou 072751HebeiChina Daqing Oil company CNPCDaqing 163000HeilongjiangChina

The Middle Jurassic Shaximiao Formation encompasses tens of meters of thick lowstand meandering valley （LMV） strata in the western Sichuan foreland basin. Ancient LMVs newly discovered in this area were further studied based on sequence stratigraphy and seismic sedimentology. The aim of the present study was to investigate the sedimentary characteristics, sequence architecture, and the controls on LMV deposition in this tectonically active basin using field survey data, seismic sections, seismic amplitude imaging, core description, and comprehensive application of drilling data. The results show the following：（1） Three regional sequence boundaries and two flooding surfaces were recognized, and the Shaximiao For- mation was divided into two-third-order sequences and four systems tracts. （2） Three sedimentary facies associations were identified： incised valley-fill, tributary channel, and overbank facies. Incised valleys are 5-17 km wide, 20-60 m deep and traceable for 120 km along their axes. （3） In the downstream segment, the role of tectonism gradually diminishes, and periodic base-level changes control the form and evolution of the incised valleys. Three types of LMVs--AI, A2, and A3--developed with changes in base level （lake level）; of these types, the base level of the A3 LMV was likely the lowest.

关键词： Sequence architecture Sedimentary characteristic Lowstand meandering valley Western Sichuandepression Shaximiao Formation

TECTONIC MIGRATION OF OIL AND GAS BASINS IN EASTERN CHINA

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Science China Chemistry 1989年第9期32卷 1125-1134页

作者：王同和 geophysical prospecting Bureau Ministry of Oil Industry of PRC Zhuozhou

This paper deals with the tectonic migration of various types of basins and the regu-larity of time-space distribution of oil and gas in the eastern China basins from the availa-ble geological, geophysical and drill data, and then a preliminary discussion is made onthe relationship between tectonic migration and oil and gas formation.

关键词： tectonic migration oil and gas basin eastern China

Effect of regularization parameters on geophysical reconstruction

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Petroleum Science 2009年第2期6卷 119-126页

作者： Zhou Hui Wang Zhaolei Qiu Dongling Li Guofa Shen Jinsong State Key Laboratory of Petroleum Resource and prospecting China University of Petroleum Beijing 102249 China Key Laboratory of CNPC geophysical prospecting China University of Petroleum Beijing 102249 China Research Institute Bureau of Geophysical Prospecting Hebei 072751 China China University of Petroleum Beijing 102249 China

In this paper we discuss the edge-preserving regularization method in the reconstruction of physical parameters from geophysical data such as seismic and ground-penetrating radar data. In the regularization method a potential function of model parameters and its corresponding functions are introduced. This method is stable and able to preserve boundaries, and protect resolution. The effect of regularization depends to a great extent on the suitable choice of regularization parameters. The influence of the edge-preserving parameters on the reconstruction results is investigated and the relationship between the regularization parameters and the error of data is described.

关键词： geophysical data inversion error of data regularization regularization parameters

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

Two exact first-order k-space formulations for low-rank viscoacoustic wave propagation on staggered grids

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Petroleum Science 2023年第3期20卷 1521-1531页

作者： Hong-Yu Zhou Yang Liu Jing Wang China Universityof Petroleum(Bejing) State Key Laboratory of Petroleum Resources and Prospecting and CNPC Key Laboratory of Geophysical ProspectingBeijing102249China China University of Petroleum(Bejing) Karamay CampusKaramayXinjiang834000China

Wave propagation in the viscoacoustic media is physically dispersive and *** excluding the numerical dispersion error from the physical dispersion in the viscoacoustic wave simu-lation is indispensable to understanding the intrinsic property of the wave propagation in attenuated media for the petroleum exploration *** recent years,a viscoacoustic wave equation char-acterized by fractional Laplacian gains wide attention in geophysical ***,the first-order form of the viscoacoustic wave equation,often solved by the conventional staggered-grid pseu-dospectral method,suffers from the numerical dispersion error in time due to the low-order finite-difference *** is challenging to completely eliminate the error because the viscoacoustic wave equation contains two temporal derivatives,which stem from the time stepping and the amplitude attenuation terms,*** tackle the issue,we derive two exact first-order k-space viscoacoustic formulations that can fully exclude the numerical error from the physical *** the homoge-neous case,two formulations agree with the viscoacoustic analytical solution very well and have the same *** the heterogeneous case,our second k-space formulation is more efficient than the first one because the second formulation significantly reduces the number of the wavenumber-space mixed-domain operators,which are the expensive part of the viscoacoustic k-space ***-merical cases validate that the two first-order k-space formulations are effective and efficient alternatives to the current staggered-grid pseudospectral formulation for the viscoacoustic wave simulation.

关键词： Viscoacoustic K-space Staggered-grid Low-rank