NSG2021 27th European Meeting of Environmental and Engineering Geophysics最新文献_第2页

Inversion of VLF Data Using a Non-Linear Smoothing Operator 利用非线性平滑算子反演VLF数据

NSG2021 27th European Meeting of Environmental and Engineering Geophysics Pub Date : 2021-08-29 DOI: 10.3997/2214-4609.202120103

M. A. Uge, G. Karcıoğlu, A. B.Tekkeli, M. S. Arslan

{"title":"Inversion of VLF Data Using a Non-Linear Smoothing Operator","authors":"M. A. Uge, G. Karcıoğlu, A. B.Tekkeli, M. S. Arslan","doi":"10.3997/2214-4609.202120103","DOIUrl":"https://doi.org/10.3997/2214-4609.202120103","url":null,"abstract":"Summary Inversion of electromagnetic induction data, including VLF, is generally realized using smooth inversion methods. The smoothness of the recovered models and the regularization of the ill-conditioned problem is ensured with smoothing matrices. Smoothing matrices are simple linear derivative matrices penalizing the resistivity differences between adjacent cells. Since these matrices are linear operators, they are calculated once at the beginning of the inversion process. Considering its structure, smoothing matrices can be considered similar to low-pass Gaussian filters. Similarly, it’s possible to define a non-linear smoothing operator based on rank order filtering. We have defined a non-linear smoothing constraint based on these filters and penalized the differences from the cells corresponding to the desired rank value. Since the defined constraint is non-linear it is re-calculated as the model parameters change. The defined constraint is tested on synthetic data and its results are compared to the results obtained with a traditional smoothing matrix. Accordingly, the defined non-linear rank order smoothing constraint can provide relatively focused, amplified structures, and can increase blockiness.","PeriodicalId":120362,"journal":{"name":"NSG2021 27th European Meeting of Environmental and Engineering Geophysics","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124791343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Surface-Waves Extraction Using a Shot-Receiver-Time Transformation 利用发射-接收时间变换提取表面波

NSG2021 27th European Meeting of Environmental and Engineering Geophysics Pub Date : 2021-08-29 DOI: 10.3997/2214-4609.202120015

Y. Ding, A. Malehmir

{"title":"Surface-Waves Extraction Using a Shot-Receiver-Time Transformation","authors":"Y. Ding, A. Malehmir","doi":"10.3997/2214-4609.202120015","DOIUrl":"https://doi.org/10.3997/2214-4609.202120015","url":null,"abstract":"Summary Seismic data contain rich information carried by different types of waves, such as direct arrivals (P- and S-waves), reflections, diffractions and surface-waves. In order to utilize a specific type of wave, one needs to isolate this wanted signal from others. We propose a method to extract and/or remove mainly the dispersive surface-waves based on their geometrical property in the shot-receiver-time domain for seismic data acquired along 2D acquisition profiles. We first assemble all shot gathers into a pseudo 3D data with dimensions of shot locations, receiver locations, and time. The shot-receiver-time domain enables us to process the data along different dimensions, not restricted to the shot domain only. With the assumption of a 1D velocity model, we find that the dispersive surface-waves in a shot gather behave linearly in a time isochrone, which cuts through all shots and receivers. The linear geometrical property of the surface-waves in the time isochrone allows us to extract them efficiently and effectively using for example curvelet-based transforms. By applying the method along the time isochrones for the time samples where surface-waves are present, surface-waves can be extracted from the pseudo 3D data. We exemplify this method using a synthetic data and a field data.","PeriodicalId":120362,"journal":{"name":"NSG2021 27th European Meeting of Environmental and Engineering Geophysics","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124620503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Capacitive Electrical Resistivity: An Alternative Non-Invasive Method for Permafrost Monitoring 电容电阻率:冻土监测的一种非侵入性替代方法

NSG2021 27th European Meeting of Environmental and Engineering Geophysics Pub Date : 2021-08-29 DOI: 10.3997/2214-4609.202120013

S. Bazin, S. Syed, G. Gilbert, B. Etzelmüller

引用次数: 1

Ensemble-Based Time-Lapse ERT Inversion with Model and Data Space Compression Through Deep Variational Autoencoders 基于深度变分自编码器模型和数据空间压缩的集成时移ERT反演

NSG2021 27th European Meeting of Environmental and Engineering Geophysics Pub Date : 2021-08-29 DOI: 10.3997/2214-4609.202120116

A. Vinciguerra, M. Aleardi

{"title":"Ensemble-Based Time-Lapse ERT Inversion with Model and Data Space Compression Through Deep Variational Autoencoders","authors":"A. Vinciguerra, M. Aleardi","doi":"10.3997/2214-4609.202120116","DOIUrl":"https://doi.org/10.3997/2214-4609.202120116","url":null,"abstract":"Summary Time-lapse electrical resistivity tomography (TL-ERT) aims to image resistivity changes in the subsurface. This is an ill-posed and non-unique inverse problem and hence the estimation of the model uncertainties is of crucial importance. To reduce the computational cost of the probabilistic inversion, model and data can be re-parameterized into low-dimensional spaces where the inverse solution can be computed more efficiently. Among the many compression methods, deep learning algorithms based on deep generative models provide an efficient approach to reduce model and data spaces. Here, we propose a TL-ERT probabilistic inversion where the data and model spaces are compressed through deep variational autoencoders, while the optimization procedure is driven by the ensemble smoother with multiple data assimilation, an iterative ensemble-based algorithm that performs a Bayesian updating step at each iteration. This method provides multiple realizations for the quantification of the uncertainty by iteratively updating an initial ensemble of models that we generate according to previously defined prior model and spatial variability pattern. A finite-element code constitutes the forward operator. We test the method on synthetic data computed over a schematic subsurface model. Our tests demonstrate the applicability and the reliability of the proposed TL-ERT inversion.","PeriodicalId":120362,"journal":{"name":"NSG2021 27th European Meeting of Environmental and Engineering Geophysics","volume":"160 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132016250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Drone Geophysics for Forecasting and Monitoring Natural Hazards 无人机地球物理预测与监测自然灾害

NSG2021 27th European Meeting of Environmental and Engineering Geophysics Pub Date : 2021-08-29 DOI: 10.3997/2214-4609.202120098

B. Dupuy, A. Tobiesen, A. Grover, A. Einbu, A. Romdhane

引用次数: 0

The potential of electrical imaging for field root zone phenotyping 电成像对田间根区表型的潜力

NSG2021 27th European Meeting of Environmental and Engineering Geophysics Pub Date : 2021-08-29 DOI: 10.3997/2214-4609.202120221

S. Garré, T. Deswaef, I. Borra‐Serrano, P. Lootens, G. Blanchy

{"title":"The potential of electrical imaging for field root zone phenotyping","authors":"S. Garré, T. Deswaef, I. Borra‐Serrano, P. Lootens, G. Blanchy","doi":"10.3997/2214-4609.202120221","DOIUrl":"https://doi.org/10.3997/2214-4609.202120221","url":null,"abstract":"Summary Providing enough food for a growing population while preserving natural resources and biodiversity is one of the challenges of the 21st century. A key pathway to maximize yields in a sustainable way is to select and grow crops that are optimally adapted to their environment. Plant performance is determined by characteristics or ‘traits’ which are partially genetically determined. Nevertheless, cultivars with the same genome (G) express different appearances or ‘phenomes’ in different environments (E) and under different management practices (M). Phenotyping the below-ground traits of plants is not straightforward, due to the opaque nature of soil. Non-invasive geophysical techniques to study the root zone have substantially advanced in recent years.Their biggest potential lies in indirect monitoring of water depletion in the root zone, especially in time-lapse mode. To explore the potential of integrating geophysics in a field phenotyping platform, we first generated a range scenarios of soil moisture dynamics for different soils and grass cultivars. Then we generated ERT data from these distributions for selected electrode setups and then inverted them back to obtain conductivity distributions. In this way, we checked the performance of different electrode arrays to delineate root water uptake patterns in various realistic conditions.","PeriodicalId":120362,"journal":{"name":"NSG2021 27th European Meeting of Environmental and Engineering Geophysics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128849209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Preliminary Evaluation of Geothermal Energy Potential in Western Part of Dahomey Basin, Southwestern Nigeria 尼日利亚西南部达荷美盆地西部地热能潜力初步评价

NSG2021 27th European Meeting of Environmental and Engineering Geophysics Pub Date : 2021-08-29 DOI: 10.3997/2214-4609.202120119

E. Ayolabi, O. Balogun, M. O. Okunubi, R. Akinwale

引用次数: 0

Gas Hazard and Origin: Near-Surface Zone of the Upper and Lower Silesian Coal Basins 瓦斯危害及成因:上西里西亚盆地和下西里西亚盆地近地表带

NSG2021 27th European Meeting of Environmental and Engineering Geophysics Pub Date : 2021-08-29 DOI: 10.3997/2214-4609.202120008

M. Kotarba, H. Sechman

{"title":"Gas Hazard and Origin: Near-Surface Zone of the Upper and Lower Silesian Coal Basins","authors":"M. Kotarba, H. Sechman","doi":"10.3997/2214-4609.202120008","DOIUrl":"https://doi.org/10.3997/2214-4609.202120008","url":null,"abstract":"Summary In 1991–2001 the all coal mines in the Lower Silesian Coal Basin (LSCB) were closed and remediated. In the middle of the 1990s mine restructuring process started at the Upper Silesian Coal Basin (USCB). At that time 65 coal mines were operational. In 2019 22 mines were still active. The main aims of this presentation are to determine the origin of soil gases in the USCB and LSCB and evaluate gas hazard caused by secondary migration of coalbed methane and carbon dioxide from Carboniferous coal-bearing strata to near-surface zone connected with the restitution of groundwater level to the original position (“piston effect”). For evaluating gas hazard surface geochemical survey and determining the origin of soil and coalbed gases, stable isotope analyses and simulation of generation of thermogenic gases by hydrous pyrolysis experiments were performed. Comprehensive geochemical, geological and hydrogeological studies carried out in the zones of closed mines in the USCB and LSCB allowed for detecting the surface range of occurrence of anomalous concentrations of methane and carbon dioxide at the surface, the mechanism of the flow of these formation gases into the near-surface zone and establish to what an extent the local population living in post-mining areas is hazarded.","PeriodicalId":120362,"journal":{"name":"NSG2021 27th European Meeting of Environmental and Engineering Geophysics","volume":"71 1-2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116720789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Integrating Electrical Resistivity and Seismic Refraction Tomography at an Active Landslide Site 活动滑坡场地的电阻率和地震折射层析成像集成

NSG2021 27th European Meeting of Environmental and Engineering Geophysics Pub Date : 2021-08-29 DOI: 10.3997/2214-4609.202120127

J. Whiteley, A. Watlet, S. Uhlemann, P. Wilkinson, J. Boyd, C. Jordan, M. Kendall, J. Chambers

引用次数: 0

Most Accurate or Fastest Possible? The Multi-Frequency SIP Excitation Enables a Choice 最准确还是最快?多频SIP激励支持选择

NSG2021 27th European Meeting of Environmental and Engineering Geophysics Pub Date : 2021-08-29 DOI: 10.3997/2214-4609.202120022

T. Radić

引用次数: 1