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Preliminary research and scheme design of deep underground in situ geo-information detection experiment for geology in Time

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International Journal of Mining Science and Technology 2024年第1期34卷 1-13页

作者： Heping Xie Ru Zhang Zetian Zhang Yinshuang Ai Jianhui Deng Yun Chen Yong Zhou Mingchuan Li Liqiang Liu Mingzhong Gao Zeqian Yang Weiqiang Ling Heng Gao Qijun Hao Kun Xiao Chendi Lou State Key laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering Sichuan UniversityChengdu 610065China College of Water Resource&Hydropower Sichuan UniversityChengdu 610065China Guangdong Provincial Key laboratory of Deep Earth Sciences and geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyShenzhen UniversityShenzhen 518060China Institute of geology and geophysics Chinese Academy of SciencesBeijing 100029China Yalong River Hydropower Development Company Limited Chengdu 610051China

The deep earth,deep sea,and deep space are the main parts of the national“three deep”strategy,which is in the forefront of the strategic deployment clearly defined in China’s 14th Five-Year Plan(2021-2025)and the Long-Range Objectives Through the Year *** is important to reveal the evolutionary process and mechanism of deep tectonics to understand the earth’s past,present and *** academic con-notation of geology in Time has been given for the first time,which refers to the multi-field evolution response process of geological bodies at different time and spatial scales caused by geological processes inside and outside the *** on the deep in situ detection space and the unique geological envi-ronment of China Jinping Underground laboratory,the scientific issue of the correlation mechanism and law between deep internal time-varying and shallow geological response is given *** research and frontier exploration on deep underground in situ geo-information detection experiments for geology in Time are designed to be carried out,which will have the potential to explore the driving force of geology in Time,reveal essential laws of deep earth science,and explore innovative technologies in deep underground engineering.

关键词： Deep underground geology in Time China Jinping Underground laboratory In situ detection

Gaussian fitting in gamma-ray spectral decomposition

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Nuclear Science and Techniques 2010年第4期21卷 214-217页

作者： FU Chen WANG Nanping Key laboratory of geo-detection (China University of geosciences Beijing) Ministry of Education Beijing 100083 China

In order to extract the information of 662-keV 137Cs spectra from the overlapping peaks with 583-keV 208Tl,609-keV 214Bi,the overlapping peaks are measured by in-situ γ-ray spectrometer using a NaI(Tl) *** spectral model is optimized by the Gaussian fitting algorithm,and the optimized fitting indexes for fitting/original value are from 0.96 to *** fitting verified by experiment is feasible for γ-ray spectrum *** full energy peak of 137Cs is extracted correctly from the overlapping peaks,it is important for in-situ γ-ray spectrometer to estimate contamination of 137Cs in radiated environment and nuclear accident.

关键词：伽玛射线高斯拟合光谱分解 137Cs 拟合算法拟合指数辐射环境重叠峰

A joint high-resolution processing method and its application for thin inter-beds

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Petroleum Science 2013年第2期10卷 195-204页

作者： Liu Zhiwei Wang Yanchun School of geophysics and Information Technology China University of Geosciences Key laboratory of geo-detection Ministry of EducationChina University of Geosciences

Seismic processing characterizing thickness and borders of thin inter-beds has gradually evolved fi＇om post-stack migration to pre-stack migration, and the latter considers both vertical and lateral resolutions. As the key processing methods for improving vertical and lateral resolution, conventional deconvolution and pre-stack time migration （PSTM） are not simply dominated by the estimation and compression of the wavelet because of its instability. Therefbre, considering the variations of wavelet frequency belbre, during and alter PSTM can obtain good common reflection point （CRP） gathers and imaging profiles of thin inter-beds. Based on the frequency characteristics of the wavelet before, during and after PSTM, a joint high-resolution processing method for thin inter-beds is proposed in this paper, including inverse Q filtering for high-frequency compensation before PSTM, optimum weighting Kirchhoff PSTM for preserving high-frequencies during PSTM, and wavelet harmonizer deconvolution tier consistent processing and frequency-band broadening after PSTM. An application to real data characterized by mudstone beds in the Oriente Basin proved that the joint high-resolution processing method is effective for determining the thickness and borders of thin inter-beds and is favorable for subsequent reservoir prediction and seismic inversions.

关键词： Thin inter-bed seismic wavelet inverse Q filtering optimum weight function harmonizerdeconvolution

3D LBFGS inversion of controlled source extremely low frequency electromagnetic data

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Applied geophysics 2016年第4期13卷 689-700,739,740页

作者： Cao Meng Tan Han-Dong Wang Kun-Peng Key laboratory of geo-detection Ministry of Education and School of geophysics and Information Technology China University of Geosciences Beijing 100083 China

The controlled source extremely low frequency （CSELF） electromagnetic method is characterized by extremely long and powerful sources and a huge measurement range. Its electromagnetic field can therefore be affected by the ionosphere and displacement current. Research on 3D forward modeling and inversion of CSELF electromagnetic data is currently in its infancy. This paper makes exploratory attempts to firstly calculate the 1D extremely low frequency electromagnetic field under ionosphere-air-earth coupling circumstances, and secondly analyze the propagation characteristics of the background electromagnetic field. The 3D staggered-grid finite difference scheme for solving for the secondary electric field is adopted and incorporated with the 1D modeling algorithm to complete 3D forward modeling. Considering that surveys can be carried out in the near field and transition zone for lower frequencies, the 3D Limited-memory Broyden-Fletcher-Goldfarb-Shanno （LBFGS） inversion of CSELF electromagnetic data is presented （in which the sources, or primary fields, are included）, with the aim of directly inverting the impedance data, regardless of where it is acquired. Derivation of the objective functional gradient is the core component in the inversion. Synthetic tests indicate that the well-chosen approximation to the Hessian can significantly speed up the inversion. The model responses corresponding to the coexistence of conductive and resistive blocks show that the off-diagonal components of tensor impedance are much more sensitive to the resistivity variation than the diagonal components. In comparison with conventional scalar inversion, tensor inversion is superior in the recoveries of electric anomalies and background resistivity.

关键词： ELF Ionosphere 3D inversion LBFGS

3D finite-difference modeling algorithm and anomaly features of ZTEM

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Applied geophysics 2016年第3期13卷 553-560,582页

作者： Wang Tao Tan Han-Dong. Li Zhi-Qiang Wang Kun-Peng Hu Zhi-Ming Zhang Xing-Dong Key laboratory of geo-detection Ministry of Education and School of geophysics and Information Technology China University of Geosciences Beijing 100083 China.

The Z-Axis tiPPer eiectromagnetic （ZTEM） technique is based on a frequency-domain airbome electromagnetic system that measures the natural magnetic field. A survey area was divided into several blocks by using the Maxwell＇s equations, and the magnetic components at the center of each edge of the grid cell are evaluated by applying the staggered-grid finite-difference method. The tipper and its divergence are derived to complete the 3D ZTEM forward modeling algorithm. A synthetic model is then used to compare the responses with those of 2D finite-element forward modeling to verify the accuracy of the algorithm. ZTEM offers high horizontal resolution to both simple and complex distributions of conductivity. This work is the theoretical foundation for the interpretation of ZTEM data and the study of 3D ZTEM inversion.

关键词： Z-Axis tipper electromagnetic finite-difference method tipper three-dimensional forward modeling airbome electromagnetic

PML Absorbing Boundary Condition for Seismic Numerical Modeling by Convolutional Differentiator in Fluid-Saturated Porous Media

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Journal of Earth Science 2011年第3期22卷 377-385页

作者：李信富 Key laboratory of geo-detection(China University of geosciences Beijing)Ministry of Education School of geophysics and Information Technology China University of Geosciences

The perfectly matched layer（PML） was first introduced by Berenger as an absorbing boundary condition for electromagnetic wave *** this article,a method is developed to ex-tend the PML to simulating seismic wave propagation in fluid-saturated porous *** non-physical boundary is used at the computational edge of a Forsyte polynomial convolutional differenti-ator（FPCD） algorithm as an absorbing boundary condition to truncate unbounded *** incor-poration of PML in Biot＇s equations is *** results show that the PML absorbing bound-ary condition attenuates the outgoing waves effectively and eliminates the reflections adequately.

关键词： seismic wave numerical modeling convolutional differentiator PML absorbing boundary condition fluid-saturated porous medium.

Modeling of Borehole Radar for Well Logging Using Pseudo-spectral Time Domain Algorithm

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Journal of Earth Science 2009年第6期20卷 978-984页

作者：林树海 Key laboratory of geo-detection (China University of geosciences Beijing) Ministry of Education School of geophysics and Information Technology China University of Geosciencess Beijing

In this article, numerical modeling of borehole radar for well logging in time domain is developed using pseudo-spectral time domain algorithm in axisymmetric cylindrical coordinate for proximate true formation model. The conductivity and relative permittivity logging curves are obtained from the data of borehole radar for well logging. Since the relative permittivity logging curve is not affected by salinity of formation water, borehole radar for well logging has obvious advantages as compared with conventional electrical logging. The borehole radar for well logging is a one-transmitter and two-receiver logging tool. The conductivity and relative permittivity logging curves are obtained successfully by measuring the amplitude radio and the time difference of pulse waveform from two receivers. The calculated conductivity and relative permittivity logging curves are close to the true value of surrounding formation, which tests the usability and reliability of borehole radar for well logging. The numerical modeling of borehole radar for well logging laid the important foundation for researching its logging tool.

关键词： borehole radar well logging pseudo-spectral time domain algorithm conductivity permittivity.

Computation of Magnetic Anomalies and Gradients for Spatial Arbitrary Posture Regular Body

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Journal of Earth Science 2009年第6期20卷 995-1002页

作者：洪东明姚长利郑元满郭伟骆遥 Key laboratory of geo-detection (China University of geosciences Beijing)Ministry of Education Beijing 100083 China School of geophysics and Information Technology China University of GeosciencesBeijing Key laboratory of geo-detection (China University of geosciences Beijing) Ministry of Education Beijing 100083 China China Aero geophysical Survey and Remote Sensing Center for Land and Resources

In the interaction computation for 3D gravity and magnetic anomalies due to arbitrarily shaped homogenous magnetized polyhedron model composed of triangular facets, there are many difficult points, such as mass computing, absence of a mature computer technique in 3D geological body modeling, inconvenient human-computer interaction, hard program coding, etc.. Based on the formulae of the magnetic field due to horizontal regular bodies, and by applying forward theory with the three-dimensional Cartesian coordinate system transformation, the forward problems of magnetic anomalies and gradient tensors for arbitrary slantwise regular bodies were solved. It is shown that the magnetic calculating expressions of the arbitrary posture regular body are corrected by comparing results with the homogeneous polyhedral body model outcome data. Furthermore, in the same condition, the former significantly reduced forward time. Applying a new forward method of regular body expressions in arbitrary posture, developed software for interaction computation between the 3D geological body model and magnetic field has advantages of fast calculation speed, easy manipulation, etc..

关键词： regular magnetic body spatial posture coordinate system transformation transformation matrix forward calculation.

Three-Dimensional P-Wave Velocity Structure of the Crust of North China

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Journal of China University of geosciences 2007年第3期18卷 257-268页

作者：魏文博叶高峰李艳军金胜邓明景建恩 State Key laboratory of geological Processes and Mineral Resources geo-detection laboratory Ministry of Education School of geophysics and Information Technology China University of GeosciencesBeijing 100083China

Since the Xingtai （邢台） earthquake in 1966, China Earthquake Administration has carried out a survey campaign along more than thirty deep seismic sounding （DSS） profiles altogether about twenty thousand kilometers long in North China to study the velocity structure of the crust and the upper mantle in this region, and has obtained a great number of research findings. However, these researches have not provided a 3D velocity structure model of the crust of North China and cannot provide seismic evidence for the study of the deep tectonic characteristics of the crust of the whole region. Hence, based on the information from the published data of the DSS profiles, we have chosen 14 profiles to obtain a 3D velocity structure model of North China using the vectorization function of the GIS software （Arc/Info） and the Kriging data gridding method. With this velocity structure model, we have drawn the following conclusions：（1） The P-wave velocity of the uppermost crust of North China changes dramatically, exhibiting a complicated velocity structure in plane view. It can be divided into three velocity zones mainly trending towards north-west. In the research area, the lowest-velocity zones lie in the Haihe （海河） plain and Bohai （渤海） Bay. Although the geological structure of the sedimentary overburden in the study area is somewhat inherited by the upper crust, there are still several differences between them. （2） Generally, the P-wave velocity of the crust increases with depth in the study area, but there still exists local velocity reversion. In the east, low-velocity anomalies of the Haihe plain gradually disappear with increasing depth, and the Shanxi （山西） graben in the west is mainly characterized by relatively low velocity anomalies. Bounded by the Taihang （太行） Mountains, the eastern and western parts differ in structural trend of stratum above the crystalline basement. The structural trend of the Huanghuaihai （黄淮海） block in the east is mainly north-east, while that of t

关键词： North China crust deep seismic sounding three-dimensional P-wave velocity structure