bluuebunny/crossref_metadata_2025_split huggingface dataset:
The analysis on PS wave reflection coefficient in equivalent porous fractured media
Authors: Dou Xiying , Wang Enli , Yang Qing , Du Bingyi , Zhang Bo 
Published: February 2021

Abstract
Combining the equivalent fractured media with Thomsen fractured media theory, the anisotropic parameters expressed in compliance are obtained. The new PS wave reflection coefficient formula presented in matrix porosity, fluid type, and fracture density were established. Numerical simulations show that the PS wave reflection coefficient in water-saturated fracture media is more sensitive to the fracture density than that in gas-saturated media; the difference between the reflection coefficients in the gas-saturated and water-saturated state greatly increases when the matrix porosity of fractured media exceeds 0.01. It shows that fracture density and matrix porosity can be used as good fluid indicators in fractured reservoir.
Application of 4D full waveform inversion in the CO2 storage monitoring: a synthetic example
Authors: Huang Zheng , Yan Xuhao , Wang Zhenyi , Zhang Pan , Zhang Fengjiao 
Published: February 2021

Abstract
The time-lapse seismic method is a technique that uses repeated seismic surveys to monitor the dynamic change of reservoir parameters. Nowadays, it has been widely used in the dynamic monitoring of marine oil and gas reservoirs. It could also be used for monitoring the CO2 injection at CO2 geological storage sites. It can give us a clear image of the injected CO2 in the reservoir. Seismic waveform inversion is a relatively new method for time-lapse monitoring. In this paper, we test the double difference full waveform inversion method on a synthetic 4D seismic data set. The preliminary results show that it is possible to use 4D full waveform inversion method to monitor the velocity changes caused by CO2 injection.
Research on Propagation Characteristics of Seismic Signal for Moving Armoured Targets
Authors: Ding Kai , Zheng Shoujun , Li Xinghua , Rong Yingjiao 
Published: February 2021

Abstract
This paper is focused on the Seismic Signal characteristics of wheel and track vehicles. The effect of vehicle speed of these two vehicles on the Seismic Signal was studied through experimental and theorical methods. The Seismic Signal s of these two vehicles with two different speeds were tested firstly. Then the measured signals were analyzed by means of the power spectrum method and the wavelet transform method, respectively. And the time- and frequency domain features of the signals were obtained subsequently. Finally, the influence of the speed and type of vehicle on the time- and frequency domain features of the signal and its propagation characteristic were investigated. The results show that, with the propagation of vehicle speed and distance, there is a similar varying law of the Seismic Signal for different vehicles. However, the difference of the time- and frequency domain feature between the two vehicles are striking.
Factors influencing microtremor data collected using nested-triangular array configurations
Authors: Chen Gaoxiang , Ge Shuangcheng , Zhao Yonghui , Chen Kanfu , Hu Shufan 
Published: February 2021

AbstractThe availability of microtremor data is potentially affected by various external factors. By combining field data and artificial interference, this work aims to determine the correlation between these factors and the dispersion curve of fundamental-mode Rayleigh waves extracted from microtremors. The first step was to obtain real, high-quality microtremor records using a triangular ten-station array of 48-m radius. Secondly, a series of artificial or semi-artificial interferences of varying type, duration, amplitude, etc., were generated and combined with the real records to imitate actual interferences. Thirdly, all the dispersion curves of the fundamental-mode Rayleigh waves of these modified microtremor records were estimated using the extended spatial autocorrelation method (ESAC). Finally, by comparing the experimental dispersion curves with the original curve, in terms of overlap ratio, we obtained useful conclusions that can be directly applied to microtremor data collection and analysis.
The Short-term Mass Change of Greenland Ice Sheet and the Atmospheric Forcing
Authors: Peng Zhenran , Wang Linsong , Chen Chao 
Published: February 2021

Abstract
In recent decades, the global warming drives the huge ice sheet melting in northern hemisphere. Previous studies on long-term melting rates of Greenland have basically reached agreement, but there is still a lack of the knowledge of the pattern the short-term ice mass change, makes it difficult to fulfill the understanding of the mechanism of the ice sheet. In this study, we used Gravity Recovery and Climate Experiment (GRACE) RL06 data to derive the time series of mass variation of Greenland Ice Sheet (GrIS), from January 2003 to December 2015. We derived the short-term mass change rate during 2003-2015 and found that the GrIS has experienced four melting stages, i.e., a steady melting (-204.4 Gt/yr) phase form 2003 to 2009, an abrupt accelerating (-384.6 Gt/yr) phase form 2010 to 2012, an abnormal pause (+24.8 Gt/yr) year in 2013 and a recovering (-207.3 Gt/yr) phase from 2014 to 2015. In addition, using ensemble empirical mode decomposition (EEMD), the high frequency signal has been removed and the annual mass change has been studied, which shows inter-annual variability. Meanwhile, we correlated the annual mass change with the Greenland Blocking Index (GBI) and North Atlantic Oscillation (NAO) during summertime and the correlation for 2003-2015 was found at r=-0.63 between the summer GBI and the annual mass change, while r=0.57 between summer NAO and the annual mass change. Our results indicate that the short-term mass change of GrIS mainly forced by atmospheric variability.
3-D Regularized focusing migration method for gravity data
Authors: Ding Yidan , Ma Guoqing , Meng Qingfa 
Published: February 2021

Abstract
Potential field migration of gravity data is a kind of method using the migration concept to efficiently obtain the density distributions subsurface. To get migration imaging results with the high resolution, we propose the regularized focusing migration method that adopts the regularization theory to realize focusing migration imaging and the conjugate migration direction method to solve the optimal solution of model parameters, which effectively improves the divergence of the conventional migration imaging. Synthetic model tests demonstrate that the proposed advanced method improves the imaging resolution significantly while guaranteeing the computational efficiency, and can bring about the relatively convergent results in a random Gaussian noise environment. This method is applied to the interpretation of the gravity anomaly from Huayangchuan, Shaanxi Province, which predicts the spatial distribution of uranium deposits.
Deep electrical structure of nailinba polymetallic mine in Balinzuo Banner, Inner Mongolia
Authors: Wang Tianqi , Han Jiangtao , Ma Guoqing , Liu Wenyu , Zhou Zikun , Kang Jianqiang , Guo Zhenyu , Yuan Tianmeng 
Published: February 2021

Abstract
The middle part of the Da hinggan mountains is an important mineral resource base in China. Since the Mesozoic, due to the uplift of the mantle, the extension of the crust, the strong intraplate volcanic eruption and magmatic intrusion, the Mesozoic magmatic tectonic belt has attracted worldwide attention. For further exploring the deep structure of this area, the final geoelectricity structure was established based on a 50-kilometer magnetotelluric sounding profile in this area. Through data acquisition, phase tensor decomposition processing, and nonlinear conjugate gradient inversion, the model reveals the main electrical structural characteristics of this area: 1. The whole has a characteristic of “longitudinal layering and horizontal block”, and the shallow electrical structure is consistent with known geological conditions; 2. There is a distribution inferred that a low-resistance anomaly appears due to the fragmentation of the surface rock layer caused by the uplift of deep intrusive rocks on the surface; 3. There are three more obvious electrical gradient zones or low-resistance anomalies in the deep part, which are presumed to be fault zones or structural erosion variable zone; 4. Three electrical gradient zones in the section divide the deep structure into four large-scale and high-resistance bodies, which reflects the spatial distribution of deep concealed granite, thereby restoring the complex anticline, secondary grade anticline, oblique uplift and depression. In addition, given the electrical structural characteristics and known the mine locations and the field exploration conditions, we conclude that the location of the prospecting target should be on a belt with Shuangjianzishan Pb-Zn-Ag mine, Nailinba Cu-Ag mine, Nailinba Fe mine, and Baiyinnuoer Pb-Zn mine. Moreover, this target is further divided into the middle area of Nailinba Cu-Ag mine and Baiyinnuoer Pb-Zn mine in combination with field surveys.
The application of ground high-precision magnetic survey to the geology and mineral investigation in Huanghe Town area
Authors: Lu Yuguo , Xiong Bin , Wang Yanhe , Su Xiaoqin 
Published: February 2021

Abstract
Three projects have been done to investigate the geology and mineral distribution in Huanghe town area A’nyemaqen-Bayanhar orogen, during the year 2013~2017. Ground high-precision magnetic method on a scale of 1:50000 has been used to study the magnetic character of the geological body and rocks. Correction has been taken in order to normalize magnetic anomaly calculated by different zero points. With the understanding of magnetic character, the distribution of stratum and geological structure can be known. After four years’ job, 16 faults have been recognized and an acid-intermediate intrusive lithosome has been found.
Application of integrated geophysical methods in geothermal exploration: a case in Zhangjiakou
Authors: Zhang Dailei , Yuan Wenzhen , Xing Yifei , Li Yanyan , Lei Xiaodong , Yu Guoming 
Published: February 2021

Abstract
Geothermal energy has become increasingly important in our energy structure as it is a kind of clean and sustainable resource. Zhangjiakou, along with Beijing, is the host city of Winter Olympic Game 2022 and has the demand of geothermal resources. In the central-south part of Zhangjiakou area, integrated geophysical exploration was carried out in 2019, including regional and local high-precision gravity, magnetotelluric (MT), controlled source audio magnetotelluric (CSAMT) and seismic measurement. Combined with geothermal geological survey, new secondary faults, the contour maps of depth of geothermal reservoir and basement are achieved, which plays a vital role in delineating geothermal anomalous area. Based on the analysis of geophysical interpretation results, geological and hydrological information, the geothermal favorable zone and drilling target areas are determined. The work done in the year of 2019 is the beginning and basis of this geothermal resource survey project, and will provide technical support for the drilling work.
Study on the application of comprehensive geophysical prospecting technology for the goaf detection in coal mine
Authors: Chen Fengge , Wang Xuan , Wang Zhihao , Zheng Jianqi 
Published: February 2021

Abstract
Aiming at the problem that drilling technology is time-consuming and challenging to be used to explore the goaf of a coal mine, a comprehensive geophysical exploration technology is proposed to quickly delineate the goaf. Through the layout of the TEM survey line to survey the development characteristics of goaf in the work area, and then with the help of magnetotelluric sounding method to verify the goaf delineated by TEM, the abnormal area of apparent resistivity obtained by the two methods were basically consistent. And it is consistent with the mining data of coal face. Based on the comprehensive geophysical exploration technology, the problem of multiple solutions of a single geophysical exploration method is solved, which provides technical support for the exploration of goaf in similar projects in this area in the future.
Analysis on the predicting significance of mid-strong earthquake swarms in Gansu and its surrounding areas
Authors: Dou Xiying , Wang Enli , Zhang Hui , Zhang Bo , Zhang Liqiong , Jiang Jiajia 
Published: February 2021

Abstract
In order to obtain the accurate prediction efficiency of earthquake swarms in Gansu province, the statistics of minor-moderate earthquake swarms that have occurred in Gansu since 1980 are performed. The earthquake swarm parameters are calculated and the precursory earthquake swarms are extracted based on the criteria of distinguishing the abnormal earthquake swarm. The precursory swarms obtained were analyzed correspondingly with the earthquakes with M≥5 in and around Gansu, and the prediction efficiency of them was evaluated. The accurate precursor index of the earthquake swarms in Gansu were summarized, which provided a judging basis for the seismic trending and made a certain contribution to earthquake prevention and disaster reduction.
Mann-Kendall Mutation Analysis of Temporal Variation of Apparent Stress in Qinba Mountains and Its Adjacent Areas
Authors: Wang Weidong , Yi Zheng , Chen Dou 
Published: February 2021

Abstract
In this abstract, we use the Mann-Kendall Mutation analysis to determine the source parameters of 125 earthquakes in the Qinba Mountains and its neighboring areas between 1997 and 2013. Seismic moments, apparent stress, and seismic radiant energy of the earthquakes were calculated. The Mann-Kendall mutation test was used to analyze the temporal data of the apparent stress. The results indicate that there occurred three downward mutation points in apparent stress in June 1998, October 1998 and March 1999, and then only one earthquake, Wudu 4.5earthquake with magnitude greater than 4 occurred in this area till September 2001. The average apparent stress decreases from 0.16 MPa from July 1997 to March 1999 to 0.15 MPa from April 1999 to September 2001. After the rising mutation point in apparent stress in October 2001, the average apparent stress increases from 0.15 MPa from April 1999 to September 2001 to 0.18 MPa from October 2001 to December 2013. A series of moderate to strong earthquakes with ML4.9, ML6.0, ML5.9, and ML5.2 then occurred in April 2003, May 2008, July 2008 and September 2009. The results demonstrate that the Mann-Kendall mutation analysis can fairly reflect the trend of apparent seismic stress, which is helpful for seismic activity prediction.
Ground penetrating radar exploration at archaeological site in Shi Village, Xia County, Shanxi Province
Authors: Wang Zhuo , Zeng Zhaofa , Zhang Ling 
Published: February 2021

Abstract
With the rapid development of city construction, it’s necessary to make archaeological exploration process more convenient, efficient and undamaged. As a result, some geophysical methods begin to be used firstly to find anomaly roughly during exploration. Ground penetrating radar (GPR), as a non-destructive and high-resolution method, should be an effective method in relatively shallow archaeological exploration. To verify the effectiveness of GPR, this paper mainly discusses the application of a combining method of GPR and Luoyang Spade – a traditional archaeological method at pre-Qin period site in Shi Village, Xia County, Yuncheng City, Shanxi Province, used GPR to find the anomaly area, then used Luoyang Spade to excavate to verify. This method can greatly shorten exploration time and reduce damage of culture relics.
A fast forward algorithm for three-dimensional gravity gradient tensor using the compact difference schemes
Authors: Hu Shuanggui , Pan Kejia , Tang Jingtian 
Published: February 2021

Abstract
We propose a fast and accurate 3D large-scale forward modeling method to compute the gravity gradient tensor, in terms of a fourth-order compact finite difference scheme and the extrapolation cascadic multigrid (EXCMG) method. Firstly, the 19-point fourth-order compact finite difference scheme with unequal mesh sizes in different coordinate directions is used to discretize the governing 3D Poisson equation. The resulted symmetric positive definite linear systems are solved by the EXCMG method. Then, the second-order derivatives (gravity gradient tensor) are calculated by solving a series of tridiagonal linear systems resulting from the fourth-order compact finite difference discretization. Finally, numerical result for a cubic model with positive density is used to verify the accuracy of our presented method. It shows that our method can give nearly fourth-order accurate approximations to gravitational potential and gravity gradient tensor. The accuracy is much higher and more efficient than traditional finite difference methods.
Application of airborne electromagnetic method in the exploration of Qingchengzi mine in Liaoning Province, China
Authors: Fu Changmin , Di Qingyun , lei Da 
Published: February 2021

Abstract
Qingchengzi area of Liaoning Province is an important concentration of polymetallic minerals in China. But with the long-term mining, Qingchengzi mining area has become a crisis mine, and the prospecting and prediction in the mining area has become a key work. The resistivity data is closely related to the existence of minerals. We carried out the VTEM airborne electromagnetic observation in this area. The primary processing results show that the inversion result is very consistent with the existing geological information. The processing results of airborne electromagnetic data will provide an important guarantee for the electrical structure, fault distribution and structural framework in the ore concentration area, as well as the delineation of the mineral target area.
Investigation and Analysis of Airborne Gamma Radiation Absorbed Dose Rate of Danjiangkou Reservoir
Authors: Li Yichuan , Yu Junchuan , Yu Xuezhong , Mi Yaohui , Hao Jingyan , Li Jiaojiao 
Published: February 2021

Abstract
Airborne gamma-ray spectrometry is widely used in regional nuclear radiation surveys and environmental nuclear radiation pollution assessments. This paper aims at analyzing the status of nuclear radiation in the Danjiangkou Reservoir area by using airborne gamma spectrometry data. Mapping of the gamma radiation air absorbed dose rate in the study area was completed by using the Beck formula and divided into three different grades according to relevant national standards. Basing on the survey results, the main sources of high radioactive anomalies in the Danjiangkou Reservoir and surrounding areas were identified. Furthermore, a protection proposal was put forward to guarantee the water quality and safety of residents in the South-to-North Water Diversion Source.
Research on the application of UAV airborne transient electromagnetic in the detection of shallow sliding surface
Authors: Wang Yong , Zhai Songtao , Zhang Xiaopei , Du Lizhi 
Published: February 2021

Abstract
In complex terrain conditions, how to achieve fast and efficient detection of the sliding surface is primary issue for the shallow landslide hazard investigation. In this paper, the UAV (Unmanned Aerial Vehicle) airborne transient electromagnetic method of Lengshui landslide in Fujian province was detecting a sliding surface. The comparison and analysis of resistivity data and borehole data show that the consistency of resistivity data and borehole geological stratification is good, and the three-dimensional distribution characteristics of the landslide can be inferred from resistivity data. Also, this paper determines the acquisition parameters of UAV airborne transient electromagnetic flight state and array types through experimental research, which has certain practical reference and guidance significance.
Three-dimensional electromagnetic method in shallow surface exploration in complex piedmont belt
Authors: Hu Zuzhi , Liu Xuejun , Wei Qiang , Yang Hui , Li Qing , Tao Deqiang 
Published: February 2021

Abstract
In the complex piedmont area, the quality of seismic data is generally poor, and it is difficult to build the shallow velocity model, which leads to the inaccurate determination of the stratigraphic and structural positions. The combination of seismic and non-seismic exploration is an effective way for oil and gas exploration in complex piedmont belt. In the northwest of Sichuan Province, the joint exploration of three-dimensional audio-magnetotelluric (AMT) and transient electromagnetic (TEM) is carried out. The transient electromagnetic data is used as static correction for audio-magnetotelluric data, and the AMT data is used to detect the shallow surface structure within 1.5km buried depth. The three-dimensional geoelectric model of the study area is obtained by using AMT three-dimensional inversion, and the geological structure interpretation is carried out by combining well logging with the statistical data of rock physical properties, which provides a basis for seismic building the shallow surface model.
Application of wavelet multi-scale analysis in the separation of aeromagnetic data potential field
Authors: Sun Hailong , Liu Yingxin , Wei Zheng , shi Xu , Wang Yahong , Lu Lichun 
Published: February 2021

Abstract
The aeromagnetic data obtained in the field is a comprehensive reflection of all geological bodies in the ground. When interpreting and inferring a field in different depths, it is necessary to separate the anomalies. As a widely used mathematical transform, wavelet transform introduces the concept of multi-scale analysis, which can effectively separate the aeromagnetic anomalies, clearly reflect the abnormal forms in different depths, and effectively. It improves the recognition accuracy of aeromagnetic data and provides a solid foundation for the processing and interpretation of aeromagnetic data.
Suggestions on Using Three-dimensional Models to Transform Mining Villages into Smart Villages in the Context of Big Data-Taking Songshumao Molybdenum Mining Area in Xingcheng, Liaoning as an Example
Authors: Li Zhongtan , Xue Linfu , Liu Jiwen 
Published: February 2021

Abstract
The construction of smart villages is the trend of future rural development. This article uses Songbei Village as an example, using unmanned aerial vehicle (UAV) to achieve efficient and fast aerial photography to establish a three-dimensional (3D) model of the area. After the mining, the current situation of Songbei Village was analyzed, and some suggestions were provided for the economic development and rural layout of Songbei Village to promote the construction of smart villages in Songbei Village.
Prediction of oil and gas distribution in K area by inheritance classification
Authors: Shi Yanling , Wang Yongtao , Liu Xuejun , Yun Zhineng , Xu Shichao , Yang Shujiang 
Published: February 2021

Abstract
Inheritance classification is an interactive multi-attribute pattern recognition method. In the interpretation of geophysical data, combined with the advantages of multiple attributes of gravity, magnetic and electromagnetic in the identification of special lithologic bodies, complex reservoirs and other targets, the heritance classification method can be used to qualitatively predict the distribution of favorable target. Multiple data complementing each other and multi-attribute intelligent classification can effectively reduce the multiple solution of geological interpretation.