bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deep learning inversion of seismic data under various observation setups
Authors: Li Duo , Cao Shuai , Yang Senlin , Xu Xinji , Jiang Peng 
Published: February 2021

Abstract
Deep learning has recently drawn massive attention for the task of geophysical inversion because of its strong non-linear mapping ability, especially for seismic inversion. Many works have been proposed. However, to simplify the problem, most of researchers only consider the simple observation setup and regard the task as the directive mapping between seismic data and velocity model, which limits the application in the real scenario. To solve this problem, we adopt the recent proposed SeisInvNet, which reconstructs the velocity model by treating each seismic trace as the essential element. Furthermore, we further extend its encoder part to make it accept randomly sampled traces as input so that it can be suitable for the inversion of seismic data under various observation setups. By comparing with the inversion results, we find that the modified SeisInvNet not only can adapt to various observation setups but also performs slightly better than the original method.
Research on the Universality of Convolutional Networks in Resistivity Inversion
Authors: Liu Benchao , Guo Qian , Pang Yonghao , Jiang Peng 
Published: February 2021

Abstract
Resistivity inversion, as an important method to study the relationship between geological models and apparent resistivity data, is a typical non-linear problem. Convolutional neural networks have huge advantages in processing complex mapping relationships between images, so they are used to solve resistivity inversion problems. The convolutional neural network’s weight sharing greatly improves the learning efficiency of the network, but there is a certain degree of incompatibility between this characteristic and the resistivity data model. In this work, the universality of the method was further verified by designing multiple complex anomalies and different background resistivities. The effectiveness of our proposed method is verified by comparing the inversion effects of different test sets with the results of traditional linear inversion.
Application of surface wave in reinforced concrete invert detection
Authors: Chen Kai , Zhang Zhifu , Zhou Yuteng 
Published: February 2021

Abstract
The thickness of reinforced concrete is an important parameter for tunnel safety, so it is necessary to detect it by non-destructive testing method. We used the multi-channel surface wave (MASW) method to derive velocity of tunnel lining structure in depth and detect thickness of reinforced concrete. The numerical experiment for irregularly dispersive media is conducted to simulate Rayleigh wave. The mode-kissing phenomenon in velocity spectrum is shown, and the modal dispersion curve can be inevitably misinterpreted. The field measurement is carried out on a new construction tunnel site and some Rayleigh wave data are acquired. We compute their velocity spectra. An alternative full velocity spectrum misfit function and a Bayesian inversion scheme are employed to retrieve tunnel lining structure. This study demonstrates that MASW method can effectively retrieve shear velocity of each layer in lining structure and detect the thickness of reinforced concrete inverts.
An application of electrical resistivity tomography to investigate leakage pathways in the exploitation of IREO
Authors: Chen Shu , Min Gang , Cheng Rong , Shu Rongbo , Qiu Lin , Liu Kang 
Published: February 2021

Abstract
For the mining of ionic rare earth ore (IREO) by in-situ leaching, the fracture structure, underground river and karst cave developed beneath the ore body, will become leakage pathways for the leaching liquors to escape and seriously reduce the recovery rate of IREO, in addition, the leach liquor along leakage pathways will also cause environmental pollution. Therefore, it is of great significance to study the deep structures and identify the leakage pathways. Our study area situates in Chang Ting county of Fujian province, which is an important rare earth deposit of China, in order to obtain high resolution deep electrical model, the electrical resistivity tomography based on multi-electrode resistivity method was used in this paper. First, we carried out multi-electrode resistivity method parameter experiment and select appropriate exploration parameters; Then, the Multi-electrode resistivity method data acquisition of 11 lines is completed by using ws-2 device mode; After that, the deep electrical structure model of the study area is obtained by inversion calculation and the thickness of the granite weathering layer (the layer containing rare earth ore) and the spatial distribution characteristics of the deep fracture structure are delineated by the deep electrical structure model of the study area. The interpretation results are consistent with the drilling results laid out in the study area. The exploration results provide important reference for the reserve evaluation of ion type rare earth mine, the sealing of leakage pathways and the layout of recovery pathways.
Application of full waveform inversion method in underground pipeline detection
Authors: Yan Xuhao , Huang Zheng , Wang Zhenyi , Zhang Pan , Zhang Fengjiao 
Published: February 2021

Abstract
Urban underground pipelines are an important part of today’s urban infrastructure. A comprehensive and systematic grasp of the current status of urban underground pipelines can provide people with basic information on urban planning, construction and management, and help people better develop and use cities and their underground space. Full waveform inversion is a well-known method that could reconstruct the underground velocity structures with high resolution. In this paper, we test the ability of full waveform inversion method in underground pipeline detection. The numerical test shows that we could use full waveform inversion to detect the regular urban underground pipelines in different sizes and depths.
Application of update lifting morphological wavelet and non-negative matrix factorization for wheeled and tracked vehicles classification
Authors: Ding Kai , Du Kai , Qi Xiaogang , Xu Yuelin , Cui Junqi 
Published: February 2021

Abstract
This paper presents an available scheme based on update lifting morphological wavelet (ULMW) and Non-negative matrix factorization (NMF) for wheeled and tracked vehicles classification. The ULWM algorithm which utilizes the update operator, means the morphological filter to replace the linear filter can preserve the impulsive shape details in seismic signal. Meanwhile the NMF method can reduce the computation cost. The traditional linear wavelet analysis and statistical analysis are compared with the presented scheme. Experimental results demonstrate that the presented scheme achieves a promising performance on extracting impulsive features of seismic signal and recognizing ground moving target.
Surface-to-Underground Nuclear magnetic Resonance Detection of Aquifer
Authors: Liu Shucai , Qiao Shuai , Jiang Zhihai , Yin Zhixian 
Published: February 2021

Abstract
The water hazard is one of the major accidents in coal mines. The existing geophysical exploration methods do not meet the precise requirements for exploration accuracy. Nuclear magnetic resonance (NMR) is currently the only geophysical method that can directly detect groundwater. This paper firstly introduces the basic principles and working methods of surface-to-underground NMR, and then gave the NMR response of the uniform earth excited by a circular loop source, at last, the NMR responses of some aquifers at different depths were simulated by the numerical modeling. The response for the observation underground is higher than that on the surface, which shows that the surface-to-underground NMR can increase the detection depth.
Exploration of 3D Simulation of Geothermal Field Based on Geophysics Exploration — Geothermal Geological Modeling
Authors: Zhu Yongshan , Zhao Ning , Mi Xiaoli , Wang Mengya , Li Qing , Yao Yao , Wei Zhuohan 
Published: February 2021

Abstract
This paper introduces a method of three-dimensional simulation of geothermal field in the study area by using the finite element method after the geothermal geological modeling based on geophysical exploration. First of all, through geophysical exploration, the three-dimensional geological model of the study area is established, and the thermal conductivity of different strata and lithology of the geological model is assigned, then the three-dimensional geothermal geological model is established;Second, set initial conditions such as surface temperature and heat source for the geothermal geological model, and then use mesh adaptive technology to perform automatic mesh division; Finally, three-dimensional geothermal field was obtained by parallel calculation in three-dimensional simulation space. This method has been applied in geothermal research in Shuguang area of Liaohe Oilfield, and the simulation results are very well.
Lithology Identification of Alluvial and Lacustrine Aquifers in Baiyangdian Area by an Airborne Transient Electromagnetic Survey
Authors: He Yiyuan , Yu Xuezhong , Liang Shengjun , Xie Rukuan , Shan Xipeng , Li Shijun 
Published: February 2021

Abstract
An airborne transient electromagnetic (TEM) has been conducted in Baiyangdian Area to map resistivity distribution within the alluvial and lacustrine aquifers. This investigation evaluated the reliability of resistivity models of the TEM data to infer lithological distribution in alluvial and lacustrine aquifers. The collected airborne TEM data were processed and inverted using spatially constrained 1D inversion method. And the 3D electrical structure, which maps electrical resistivity trends to depths of about 160 m, can be established through interpolation. Comparison of the resistivity models to drill logs indicates resistive permeable coarse-grained sediments and conductive fine-grained sediments which are relatively impermeable. Hence, the 3D electrical structure that are related to lateral and vertical variation in lithology, can serve as baseline information for groundwater potential identification. This research indicates that groundwater detection is an ideal target for mapping with airborne TEM techniques because of the high electrical resistivity of permeable coarse-grained deposits and its contrast with impermeable fine-grained deposits.
Using GRACE and hydrological data to estimate changes of evapotranspiration in the Three Gorges Reservoir
Authors: Zheng Yuhao , Wang Linsong , Fu Zhengyan , Peng Zhenran , Chen Chao 
Published: February 2021

AbstractThe Three Gorges Project (TGP) has driven changes in water storage, which directly affected the migration and redistribution of land water in the Yangtze River Basin. As a result, a new water balance is established, regional or local evapotranspiration fluctuates, and it may change the climate and weaken geological stability. In this study, we use data from GRACE gravity satellites, hydrological models, remote sensing, and in-situ observations to monitor the spatiotemporal evolution of terrestrial water changes and in the Three Gorges Reservoir (TGR) area, and then to estimate the evapotranspiration induced by water storage fluctuations in the TGR. We calculated the downscaled GRACE results based on the Land Surface Models (LSMs) and scale factor method, which can improve the signal amplitude and spatial differences in the study area and its surrounding areas. Combining the scaled GRACE-derived total water storage changes, precipitation and surface runoff, our estimated evapotranspiration (ET) in the TGR area is highly consistent with the MOD16 global ET results from 2002 to 2016. Seasonal ET changes are mainly driven by climate and rainfall, but GRACE-derived ET shown that the fluctuations of evapotranspiration are also affected by artificial water storage directly, e.g., in the main three water impounding stages (2003, 2006, and 2008), the elevation of the water level caused an abnormal increase in regional ET, but during the water drainage period (spring and autumn), high precipitation did not have a great impact on ET. Our results show that the coverage area of the reservoir area and the short-term fluctuations of the reservoir capacity are the main factors determining the ET in the TGR area.
Inspiration of magma source and intrusion of Niukutou polymetallic ore area: evidence from audio frequency magnetotelluric(AMT)
Authors: Han Song , Lu Lichun , Li Ding , Guo Hua , Chang Chang , Zheng Qiang 
Published: February 2021

Abstract
Niukutou research area is located in the north slope of Qimantage mountain in the east Kunlun, which is an important part of the lead, zinc, copper and iron metallogenic belt. The regional mineralization is inseparable from Indosinian magmatism. However, the research area is covered by Quaternary stratum area and the trace of magmatic activity is difficult to find. In order to further understand the underground structure, the spatial distribution characteristics of magmatic rocks and the relationship with polymetallic mineralization of the research area, the audio-frequency magnetotelluric (AMT) survey is deployed. Through the comprehensive analysis based on the electrical structure, we found that the granites encountered in the research area are from the magma source corresponding to the deep F3 channel, the granites are occurred as the veins from multi-channels. There are no granites base in the profiles and the regional metallogeny are controlled by the magma activity and the fault F3.In geologic modeling process of groundwater system, block modeling needs to be established.
Analysis of IP response characteristics in wells on undulating topography
Authors: Wang Xinyu , Yan Liangjun , Mao Yurong , Zhou Lei , Xie Xingbin 
Published: February 2021

Abstract
This paper studies the effect of undulating topography on resistivity method and induced polarization (IP) method between the wells. The 3D forward modeling of borehole resistivity/induced polarization method is realized by abnormal potential algorithm based on unstructured finite-element method (FEM). The algorithm is verified in layered medium and spherical abnormal bodies. We studied the response characteristics of apparent resistivity and apparent polarizability in well-well mode and the situation when the source is at different positions in the well, and analyzed the effects of undulating topography on resistivity and induced polarization. The results show that the apparent polarizability and apparent resistivity response have a great relationship with the depth of the emission source in the well, the relative position of the emission source and the measurement electrode. The undulating topography only affects the measuring electrodes at a short distance, and it has a greater impact on the low-resistance anomalous body.
Magnetotelluric multi-reference array data processing algorithm
Authors: Zhou Cong , Tang Jingtian , Yuan Yuan , Deng Juzhi , Shi Fusheng , Li Yong 
Published: February 2021

Abstract
Rational use of multiple remote reference data is an important way to improve the data quality of MT method. Based on the electromagnetic array data processing model, a data processing algorithm with multiple reference stations is proposed. Firstly, reference channels are selected from multiple remote stations to construct the natural field dominated reference data array; then the polarization parameters of natural sources are extracted from the reference data array by robust principal component analysis method; the parameters are then applied to the target array, which constructed by data from the stations to be processed, to estimate the target tensor impedances by robust estimation method. Finally, the effectiveness of the proposed algorithm is discussed by comparing it with the robust least squares and conventional remote reference methods, using a case study in east China. The results show that the new scheme is an effective strategy by using the multiple reference channel data, which can improve the quality of MT data processing in noisy environment and provide a reasonable correction for MT “dead band” distortions.
Wavelet Nyström fast numerical algorithm for the integral equation in scattering problems
Authors: Xu Yangyang , Shang Yaoda , Meng Xiangyu , Sun Jianguo 
Published: February 2021

Abstract
We present a fast Nyström algorithm to solving the inhomogeneous Lippmann– Schwinger equation for scattering wave field problems. This algorithm transforms the discrete matrix of the linear integral operator into a sparse matrix utilizing the compression property of the wavelet transform. The sparse linear equations are solved by the double conjugate gradient method. In the numerical part, we verified the feasibility and effectiveness of our method by modeling the wave field for a synthetic model.
Inversion of 1D audio magnetotelluric data based on residual convolution neural network
Authors: Liu Zhengguang , Ren Zhengyong , Tang Jingtian , Zhang Liang 
Published: February 2021

Abstract
The 18-layer residual convolution neural network (ResNet18) were used for 1D audio magnetotelluric(AMT) data inversion. In order to avoid the dependence of the traditional iterative algorithm on the initial model and calculate sensitivity matrix, we have trained ResNet18 via providing model parameters instantaneously. The residual network was used to solve the problem of deep network gradient disappearing. Deep network and lots of sample data could improve the generalization of the network. The experimental results showed that it could obtain reliable inversion results for synthetic AMT data.
Study on conical source transient electromagnetic based on AWPSO algorithm
Authors: Huang Gang , Yang Haiyan 
Published: February 2021

Abstract
The transient electromagnetic conical field source device can effectively reduce the inductance between the coils and improve the resolution of the small device to detect the shallow underground layer. However, the conventional inversion method requires an initial model and has the disadvantage of low inversion precision. Combined with the results of previous studies, this paper proposed an adaptive weighted particle swarm optimization (AWPSO) algorithm based on Sigmoid function through the analysis and research of PSO, which solved the problem of artificial initial model and low precision of inversion results. By calculating the test function, the algorithm can effectively improve the searching ability of particle swarm optimization algorithm. Several different typical geoelectric models are designed, and the algorithm is applied to data inversion of transient electromagnetic geoelectric model. Combined with the measured data of a hot spring practice area, the inversion calculation and interpretation of the sounding data were carried out, and the inversion calculation results were confirmed by the geological and hydrological data. The results show that the proposed particle swarm optimization algorithm has a high inversion fitting degree to the theoretical model and the measured data, achieves the separation of the apparent resistivity anomalies in the shallow subsurface, and improves the resolution and interpretation accuracy of the measured data in the conical field source transient electromagnetic method.
FCT finite difference forward simulation of the submarine viscoelastic seismic wavefield
Authors: Xi Jianjun , Cui Dandan 
Published: February 2021

Abstract
The actual seafloor is the typical viscoelastic medium, covered with unconsolidated geological bodies like sand, gravel, sludge, and detritus on the surface. When the seismic wave is propagating therein, viscosity of the seafloor strata will cause seismic wave energy loss, amplitude attenuation and gradual frequency reduction at the wavelet center, and then the accurate subsurface information and high-resolution images cannot be obtained directly from the seismic data due to the reduced signal resolution and SNR. Considering seabed viscoelastic media properties, a model including quality factor, density, and other physical parameters, the flux corrected transport (FCT) algorithm is established to describe the target seafloor and solve the wave equation, in which, the finite difference numerical simulation method of FCT is used to suppress the numerical dispersion generated by differential calculation in coarse grid, improve the seismic wavefield simulation accuracy and computational efficiency. Based on the submarine ancient channel types and the basic characteristics of the real and typical marine geological phenomena, the seismic responses to the three types of submarine ancient channel models, which are straight, curved and braided, are calculated, with good results acquired.
A new landslide classification method based on electrical differences and relevant examples
Authors: Xie Xinglong , Ma Xuemei , Ming Yuanyuan , Li Qinchen , Ren Zhengwei 
Published: February 2021

Abstract
A new landslide classification method based on electrical differences is proposed in this paper. The electrical parameters are obtained by the high-density electrical method, which is commonly used in landslide exploration. In this paper, landslides are divided into four categories based on the electrical difference between overburden and bedrock, and on this basis, the landslides are further divided into four categories according to the local electrical difference of landslides, totally eight kinds of landslides. The high-density resistivity method works well for exploration of both type I and type II slides. However, for type III and type IV, other geophysical methods should be supplemented. For type V-VIII landslides, they are simplified into type I-IV landslides in sections according to their electrical characteristics. As for complex landslides caused by multiple factors, more survey lines need to be laid systematically, combined with various methods, as well as information of drilling and trenching for comprehensive prospecting. The landslide classification method proposed in this paper provides some basis and reference for landslide exploration.
3D characterization of archaeological remains buried under obstacles using annular array electric resistivity tomography
Authors: Shi Zhanjie , Yu Tianxiang , Xu Liuwei 
Published: February 2021

Abstract
When archaeological remains are buried under buildings or other obstacles, it is very difficult to detect them by performing the traditional electric resistivity tomography (ERT) which commonly sets out survey lines right above those remains. We presented an annular array ERT method to solve the above problem. All electrodes were arranged around the obstacles in an annular array form. The apparent resistivity data were acquired through a special electrode shifting design. The electrode moved in the same serial number order with the cross diagonal survey of a 3D rectangular array. ERT apparent resistivity data were inverted by a 3D resistivity inversion package named RESINVM3D. The proposed method was tested using a synthetic model and field data. Synthetic results show that the target buried under obstacles can be imaged through the annular array. The result of field case indicates grave chamber buried under grave mound can be characterized using the proposed method. We conclude that the annular array ERT is an effective and valuable scheme for the detection and characterization of archaeological remains buried under obstacles.