Exploration Geophysics最新文献_第9页

Enhanced data fidelity after ground roll attenuation using conditional standard deviation clustering obtained from the GARCH model 利用GARCH模型获得的条件标准差聚类增强了地面滚转衰减后的数据保真度

IF 0.9 4区地球科学

Exploration Geophysics Pub Date : 2022-11-08 DOI: 10.1080/08123985.2022.2135430

Mohammad Amin Aminian, M. Riahi

引用次数: 0

Random noise attenuation using the novel Estimated Noise Pattern Denoising Algorithm 一种新的估计噪声模式去噪算法在随机噪声衰减中的应用

IF 0.9 4区地球科学

Exploration Geophysics Pub Date : 2022-11-07 DOI: 10.1080/08123985.2022.2140654

Mohammad Iranimehr, M. Riahi, A. Goudarzi

引用次数: 0

Cross-validation of time-depth conversion and evaluation of different approaches in the Mesopotamian Basin, Iraq 伊拉克美索不达米亚盆地时间-深度转换的交叉验证和不同方法的评价

IF 0.9 4区地球科学

Exploration Geophysics Pub Date : 2022-11-07 DOI: 10.1080/08123985.2022.2140653

Omar N. A. Al-Khazraji

{"title":"Cross-validation of time-depth conversion and evaluation of different approaches in the Mesopotamian Basin, Iraq","authors":"Omar N. A. Al-Khazraji","doi":"10.1080/08123985.2022.2140653","DOIUrl":"https://doi.org/10.1080/08123985.2022.2140653","url":null,"abstract":"The time-depth conversion process is a significant task in seismic interpretation to establish the link between geophysical information in the time domain and geological information in the depth domain at/away from well locations. Selecting the suitable velocity model for time-depth conversion to generate an accurate depth map is difficult if the accuracy of these models is unknown. In the current study, the cross-validation technique is used as a tool to diagnose and evaluate the performance of time-depth conversion at/away from well controls to predict the depth of Top Hartha and Zubair reservoirs using the dataset of East Baghdad Oil Field. To test this technique, four common velocity model approaches used for time-depth conversion with different scenarios of velocity parameters (initial velocity V 0 and depth gradient (K)) were applied to produce ten velocity models (1–10). According to the gradient variation of velocity with depth, check shot analysis, the velocity models (1–10) include three key velocities layer-cakes: Layer 1 (Middle Miocene-Upper Cretaceous), Layer 2 (Upper Cretaceous), and Layer 3 (Lower Cretaceous) with 18 horizons from Middle Miocene down to Lower Cretaceous. The cross-validation analysis reveals that the velocity model with a variable surface initial velocity and constant depth gradient (Model 9) was the most accurate with fewer mistie between actual and predicted depth. Consequently, this model is used to construct the depth map of the Hartha and Zubair reservoirs. Finally, this study progresses a workflow that can be applied to the region with any geological setting to investigate time-depth conversion uncertainty.","PeriodicalId":50460,"journal":{"name":"Exploration Geophysics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2022-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47966210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Analysis of subsurface velocity using CMP gathers picked up by unshielded GPR system: results from an experimental NAPL contaminated test site 利用无屏蔽GPR系统采集的CMP数据分析地下速度:来自试验性NAPL污染试验场的结果

IF 0.9 4区地球科学

Exploration Geophysics Pub Date : 2022-11-04 DOI: 10.1080/08123985.2022.2131390

Ibrar Iqbal, Bin Xiong, G. Tian, Yu Lu, Yang Yang

{"title":"Analysis of subsurface velocity using CMP gathers picked up by unshielded GPR system: results from an experimental NAPL contaminated test site","authors":"Ibrar Iqbal, Bin Xiong, G. Tian, Yu Lu, Yang Yang","doi":"10.1080/08123985.2022.2131390","DOIUrl":"https://doi.org/10.1080/08123985.2022.2131390","url":null,"abstract":"Adequate knowledge of velocity is required for accurate data imaging and depth conversion, as well as for quantifying the distribution of soil water content. Without complementary borehole information in the form of dielectric permittivity and/or porosity logs along the profile, it is currently impossible to reliably estimate the high-frequency electromagnetic velocity distribution in the probed subsurface region. Here, we present a new method for calculating the precise subsurface velocity structure from ground penetrating radar (GPR) reflection data that does not require boreholes or log data. This study investigates the ability of the pulse_EKKO PRO GPR system to predict a vertical profile for the possible velocity estimation of a layered and contaminated geophysical test site in Hangzhou, China. All data were acquired and saved on the GPR system in various files (projects) before analysis using GPR software to obtain approximated velocity modelling using common midpoint (CMP) gathers. Using the velocity spectrum analysis, a vertical profile of the interval velocities can be derived from each CMP gather. The findings of this study indicate that the proposed method is effective and sustainable. Furthermore, owing to the efficacy of the method in terms of field effort and computational complexity, it can easily be expanded to 3D GPR velocity exploration, increasing its importance in comparison to standard offset-based techniques for estimating velocity using GPR.","PeriodicalId":50460,"journal":{"name":"Exploration Geophysics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2022-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48064348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A novel equivalent staggered-grid finite-difference scheme and its optimization strategy for variable-density acoustic wave modelling 变密度声波模型的等效交错网格有限差分格式及其优化策略

IF 0.9 4区地球科学

Exploration Geophysics Pub Date : 2022-11-02 DOI: 10.1080/08123985.2022.2034477

Jing Wang, Yang Liu, Hongyu Zhou

{"title":"A novel equivalent staggered-grid finite-difference scheme and its optimization strategy for variable-density acoustic wave modelling","authors":"Jing Wang, Yang Liu, Hongyu Zhou","doi":"10.1080/08123985.2022.2034477","DOIUrl":"https://doi.org/10.1080/08123985.2022.2034477","url":null,"abstract":"Compared with the standard staggered-grid finite-difference (FD) methods, equivalent staggered-grid (ESG) ones can significantly reduce the computational memory for acoustic wave modelling in the variable-density media. To further enhance the simulation efficiency and accuracy, one way is to optimize the FD coefficients, another way is to design new FD stencils. In this paper, we propose a modified ESG (M-ESG) scheme which can significantly accelerate the wavefield simulation process while preserving or even improving the modelling accuracy. We calculate the FD coefficients by approximating the temporal and spatial derivatives simultaneously based on time–space domain (TS-D) dispersion relation of the discrete wave equation. Our M-ESG scheme in the TS-D can maintain basically the same accuracy as the conventional ESG (C-ESG) one when the FD coefficients are derived by the Taylor-series expansion (TE) approach. Note that the TS-D dispersion relation is nonlinear with respect to the FD coefficients of the C-ESG scheme, so it is difficult to obtain the optimized FD coefficients for the discrete wave equation. However, we can minimize the L2-norm error of the dispersion relation based on our M-ESG scheme to implement a linear FD coefficients optimization strategy, which is easy and efficient. Comparisons with TE- and optimization-based C-ESG schemes demonstrate the accuracy, stability, and efficiency superiorities of our TE- and optimization-based M-ESG ones.","PeriodicalId":50460,"journal":{"name":"Exploration Geophysics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47640463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Geophysical studies around abu gharadig basin, North Western desert, Egypt 埃及西北沙漠abu gharadig盆地周围的地球物理研究

IF 0.9 4区地球科学

Exploration Geophysics Pub Date : 2022-09-21 DOI: 10.1080/08123985.2022.2123736

Belal Mohamed Abdelhamed, Sultan Awad Sultan Araffa, T. Abdelhafeez

{"title":"Geophysical studies around abu gharadig basin, North Western desert, Egypt","authors":"Belal Mohamed Abdelhamed, Sultan Awad Sultan Araffa, T. Abdelhafeez","doi":"10.1080/08123985.2022.2123736","DOIUrl":"https://doi.org/10.1080/08123985.2022.2123736","url":null,"abstract":"The current study aims to determine the basement configuration and basement-related structural elements of the Abu Gharadig basin.: We delineated subsurface features that affect the configuration of reservoirs in the study area using an integrated interpretation of potential field and seismic reflection data. The study area lies in the North-Western Desert of Egypt to the east of the Qattara Depression, between latitudes 29° 00’ and 30° 00’ N and longitudes 28° 00’ and 30° 00’ E. Gravity data interpretation delineates shallow features, with NNE-SSW as the major trend and NW-SE as the minor trend. Given that the Euler structural index is approximately zero, these trends probably represent major faults with steep dips and large throws, which juxtapose considerable thicknesses of rocks with contrasting magnetization. On the other hand, the most common tectonic trends prevailing in the deeper levels are the NEN-SWS and NW-SE as the major trends and ENE-WSW as a minor trend. At the same time, the dominant tectonic trend from the Euler solution is NNW-SSE as a major trend and NNE -SSW and WNW-ESE as minor trends. The interpretation of magnetic data indicates the study area dissect by different trends where the trends of shallow features are NNW-SSE as a major trend and E-W as a minor trend. On the other hand, the most common tectonic trends prevailing in the deeper levels are the NNE-SSW and WNW-ESE as major trends and E-W, ENE-WSW, NEN-SWS, and NWN-SES as minor trends. At the same time, the dominant tectonic trend from the Euler solution is N-S as a major trend and NW-SE and NE-SW as minor trends. In the study area, the depth to the top of the basement rocks ranges from 1731.7 m to more than 4736.6 m. Main faults only affect the Lower and Upper Cretaceous sequences, according to seismic interpretation, and appear to be in two trends, the NW-SE and NWN-SES. These structural trends affect the configuration of oil reservoirs in the study area. The study area contains valuable reservoirs according to boreholes drilled in the stud area.","PeriodicalId":50460,"journal":{"name":"Exploration Geophysics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2022-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49285152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Application of complex resistivity survey in an epithermal Au-Ag deposit, South Korea 复电阻率测量在韩国某浅成热液型金银矿床中的应用

IF 0.9 4区地球科学

Exploration Geophysics Pub Date : 2022-09-08 DOI: 10.1080/08123985.2022.2091986

J. Son, Seok-Jun Yang, S. Shin, Samgyu Park

{"title":"Application of complex resistivity survey in an epithermal Au-Ag deposit, South Korea","authors":"J. Son, Seok-Jun Yang, S. Shin, Samgyu Park","doi":"10.1080/08123985.2022.2091986","DOIUrl":"https://doi.org/10.1080/08123985.2022.2091986","url":null,"abstract":"Electrochemical reactions at the interface between groundwater and sulphides are remarkable. Sulphides in mineralised zones are relatively abundant compared to hydrothermal alteration zones and host rocks. Complex resistivity is a geophysical tool for visualising difference between various subsurface electrochemical reactions. The epithermal Au–Ag mineralisation at Moisan hill (South Korea) occurs in the extensively disseminated pyrite zone, a typical feature of advanced argillic and argillic alteration zones. The epithermal vein at Moisan had a strike length of >500 m horizontally and approximately 300 m vertically and was controlled by the WNW fault zone. In this context, the deposit was subjected to a test bed to demonstrate the applicability of the complex resistivity survey for mineral exploration. To compare complex resistivity results with geological characteristics of epithermal mineralisation, we visualised the complex resistivity survey results and Au–Ag mineralised zones confirmed by drilling cores in three dimensions. The quartz veins of the targets showed high resistivity and a strong phase response; however, both the alteration zones and host rocks showed lower resistivity and a weaker phase response than the target zones. Through a step-by-step clustering analysis, a simple map integrating both kinds of the geophysical models was generated, to identify the boundary between the target and background. Geologic survey and drilling investigations indicate that the target is well-localised in a mineralised zone. The complex resistivity survey is a useful tool for exploring epithermal Au–Ag deposits.","PeriodicalId":50460,"journal":{"name":"Exploration Geophysics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2022-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42774109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Estimation of pore aspect ratio and capillary pressure coefficient to predict S-wave velocity based on rockphysics modeling in orthorhombic anisotropic reservoirs 基于岩石物理模型的正交各向异性储层孔隙长径比和毛细管压力系数估算S波速度

IF 0.9 4区地球科学

Exploration Geophysics Pub Date : 2022-09-02 DOI: 10.1080/08123985.2022.2117602

Fan Wu, Jingye Li, Xiaohong Chen, W. Geng, Wei Tang

{"title":"Estimation of pore aspect ratio and capillary pressure coefficient to predict S-wave velocity based on rockphysics modeling in orthorhombic anisotropic reservoirs","authors":"Fan Wu, Jingye Li, Xiaohong Chen, W. Geng, Wei Tang","doi":"10.1080/08123985.2022.2117602","DOIUrl":"https://doi.org/10.1080/08123985.2022.2117602","url":null,"abstract":"Accurate prediction of S-wave velocity is of great significance in many aspects, such as inversion, migration, brittleness index calculation, etc. Under normal circumstances, the more types of known input parameters there are, the more accurate the rock’s specific situation, and the more accurate the predicted S-wave velocity. However, considering the actual situation, the types of parameters obtained through logging curves are relatively limited. Some parameters cannot be measured and calculated, which limits the accuracy of S-wave prediction. Therefore, if the parameters can be predicted, a more accurate underground situation is able to described by these parameters. Through rockphysical analysis, the pore aspect ratio and capillary pressure coefficient can affect the velocity. In this way, a new orthorhombic (ORT) rockphysical modeling process considering the pore aspect ratio and capillary pressure coefficient is proposed. The model consists of VTI anisotropy from compaction or textural alignment of minerals, and HTI anisotropy from high-angle fractures caused by stratum pressure, thus showing ORT anisotropy. The inputs of the model can be multiple minerals. And the pore structure and the modulus of the mixed fluids in the pores are considered. We use inverse theory (quantum genetic algorithms) to obtain the pore aspect ratio and capillary pressure coefficient and finally calculate the S-wave velocity through the above parameters. The calculation results in a shale reservoir show that the predicted S-wave velocity is in good agreement with the real logging data. This shows that the proposed rockphysical modeling process and inverse algorithm method are effective.","PeriodicalId":50460,"journal":{"name":"Exploration Geophysics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48311851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

High-resolution imaging: an approach by compensating absorption and dispersion using inverse Q filtering 高分辨率成像:一种利用反Q滤波补偿吸收和色散的方法

IF 0.9 4区地球科学

Exploration Geophysics Pub Date : 2022-09-02 DOI: 10.1080/08123985.2022.2119126

Jizhong Wu, Ying Shi, Weihong Wang, Qianqian Yang

引用次数: 0

Fast hyperparameter-free spectral approach for 2D seismic data reconstruction 二维地震数据重建的快速无超参数谱方法

IF 0.9 4区地球科学

Exploration Geophysics Pub Date : 2022-08-30 DOI: 10.1080/08123985.2022.2114828

Hongjingtian Zhao, Zhihui Liu, Xue Luo, Yuanyuan Li

{"title":"Fast hyperparameter-free spectral approach for 2D seismic data reconstruction","authors":"Hongjingtian Zhao, Zhihui Liu, Xue Luo, Yuanyuan Li","doi":"10.1080/08123985.2022.2114828","DOIUrl":"https://doi.org/10.1080/08123985.2022.2114828","url":null,"abstract":"Reconstruction of missing seismic data is a critical procedure for subsequent applications like multiple wave suppression, wave-equation migration imaging and so on. In this paper, a fast, hyperparameter-free and sparse iterative spectral estimation approach is proposed for the reconstruction of two-dimensional seismic data of randomly missing traces. The proposed approach is based on the harmonic structure of the frequency slice of seismic data and the weighted covariance fitting criterion. Specifically, the method first iteratively estimates the spectrum of the frequency slice by solving a weighted covariance fitting problem. Then, the missing data is reconstructed by using the estimated spectrum and a linear minimum mean-squared error estimator. However, the spectral estimation depends on matrix-vector multiplications for each iteration, which has a high computational cost when the data increase to a large size. To solve this problem, a fast iterative technology is proposed by using an inverse fast Fourier transform, which fully exploits the Hermitian–Toeplitz structure of the covariance matrix and the exponential form of the steering vector and it significantly reduces the computational complexity. The proposed algorithm is hyperparameter-free, can provide super spectral resolution, and thus obtain better reconstruction performance. The experimental results of synthetic and real seismic data show that the proposed algorithm has higher reconstruction accuracy and lower computational complexity compared to other commonly used reconstruction algorithms.","PeriodicalId":50460,"journal":{"name":"Exploration Geophysics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2022-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42405138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0