H2S origin, generation, and distribution in the Etame Marin Permit, offshore Gabon: A three-dimensional migration modeling prediction using field data

AbstractThis paper is concerned with the inverse scattering problem for the three-dimensional Maxwell equations in bi-anisotropic periodic structures. The inverse scattering problem aims to determine the shape of bi-anisotropic periodic scatterers from electromagnetic near-field data at a fixed frequency. The factorization method is studied as an analytical and numerical tool for solving the inverse problem. We provide a rigorous justification of the factorization method which results in the unique determination and a fast imaging algorithm for the periodic scatterer. Numerical examples for imaging three-dimensional periodic structures are presented to examine the efficiency of the method.

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ACOUSTIC THREE-DIMENSIONAL EFFECTS AROUND THE TAIWAN STRAIT: COMPUTATIONAL RESULTS

Journal of Computational Acoustics ◽

10.1142/s0218396x99000035 ◽

1999 ◽

Vol 07 (01) ◽

pp. 15-26 ◽

Cited By ~ 8

Author(s):

CHI-FANG CHEN ◽

JANG-JIA LIN ◽

DING LEE

Keyword(s):

Field Data ◽

Bottom Topography ◽

Three Dimensional ◽

Propagation Model ◽

Computational Results ◽

Submarine Canyons ◽

Offshore Area ◽

Ocean Environment ◽

The Taiwan Strait ◽

Good Agreement

A set of experiments were performed in the offshore area off the coasts of Taiwan and three-dimensional (3-D) measurements recorded. The 3-D effect on underwater propagation due to azimuthal variation of bottom topography is studied for the offshore regions southwest of Taiwan, where submarine canyons exist. A 3-D acoustic propagation model, FOR3D, is used to detect the 3-D effect. Computational results show that the 3-D effect is more prominent along the axis of the canyon than across it. Calculations show a very good agreement with field data, which indicate that the 3-D effect exists in this realistic ocean environment.

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Modern techniques in illustration and recording in geology

Geological Field Sketches and Illustrations ◽

10.1093/oso/9780198835929.003.0016 ◽

2019 ◽

pp. 267-282

Author(s):

Matthew J. Genge

Keyword(s):

Field Data ◽

Earth Science ◽

Three Dimensional ◽

Field Observations ◽

Valuable Data ◽

New Methods ◽

Geological Features ◽

Field Notes ◽

Digital Methods ◽

Three Dimensional Models

Advances in technology have enabled new methods in the acquisition and recording of field data in geology and its presentation within publications. These techniques compliment, rather than replace, traditional field observations. This chapter describes the use of photogrammetry and aerial drone surveys in constructing three-dimensional models of geological features, which provide valuable data when combined with field notes on lithology. Digital methods in the analysis and processing of images are discussed together with methods in digital drawing and painting to produce publication-ready diagrams for Earth Science. Photographs for use in publications should be corrected to ensure optimal contrast and brightness.

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Effects of three-dimensional electric field on saltation during dust storms: An observational and numerical study

10.5194/acp-2019-439 ◽

2019 ◽

Author(s):

Huan Zhang ◽

You-He Zhou

Keyword(s):

Electric Field ◽

Field Data ◽

Numerical Study ◽

Three Dimensional ◽

Vertical Component ◽

Dust Storms ◽

Dust Particles ◽

Sand Transport ◽

Dust Transport ◽

Dust Events

Abstract. Particle tribo-electrification being ubiquitous in nature and industry, potentially plays a key role in dust events, including the lifting and transport of sand and dust particles. However, the properties of electric field (E-field) and its influences on saltation during dust storms remain obscure as the high complexity of dust storms and the existing numerical studies mainly limited to one-dimensional (1-D) E-field. Here, we quantify the effects of real three-dimensional (3-D) E-field on saltation, through a combination of field observations and numerical modelling. The 3-D E-fields in the sub-meter layer from 0.05 to 0.7 m above the ground during a dust storm are measured at Qingtu Lake Observation Array site. The measured results show that each component of the 3-D E-field data nearly collapses on a single 3-order polynomial curve when normalized. Interestingly, the vertical component of the 3-D E-field increases with increasing height in the saltation layer during dust storms. Such 3-D E-field data close to the ground within a few centimeters has never been reported and formulated before. Using the discrete element method, we then develop a comprehensive saltation model, in which the tribo-electrification between particle-particle midair collisions is explicitly accounted for, allowing us to evaluate the tribo-electrification in saltation properly. By combining the results of measurements and modelling, we find that although the vertical component of the E-field (i.e. 1-D E-field) inhibits sand transport, 3-D E-field enhances sand transport substantially. Furthermore, the model predicts that 3-D E-field enhances the total mass flux by up to 63 %. This suggests that a truly 3-D E-field consideration is necessary if one is to explain precisely how the E-field affects saltation during dust storms. These results will further improve our understanding of particle tribo-electrification in saltation and help to provide more accurate characterizations of sand and dust transport during dust storms.

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Three-dimensional mobile mapping system and its use in road engineering

MATEC Web of Conferences ◽

10.1051/matecconf/201819604082 ◽

2018 ◽

Vol 196 ◽

pp. 04082

Author(s):

Zuzana Florkova ◽

Lukas Duris ◽

Michal Veselovsky ◽

Stefan Sedivý ◽

Dasa Kovalova

Keyword(s):

Data Collection ◽

Field Data ◽

Three Dimensional ◽

Research Paper ◽

Mobile Mapping ◽

Road Engineering ◽

Mapping System ◽

Field Data Collection ◽

Mapping Technology ◽

Mobile Mapping System

The paper focuses on the issue of the use of three-dimensional mobile mapping system and the following processing of obtained data. The first part is devoted to the description of the three-dimensional mobile mapping technology using LiDAR, specifically to the mobile three-dimensional scanner - Lynx SG1 from Teledyne OPTECH. It describes into more details the process of works from the field data collection to their so called "postprocessing" as well as a variety of output options and interpretations of results obtained in the measurements. Advantages of the system together with its limits of use are summarized in the conclusion of the research paper.

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Real-Time Reconstruction of Contaminant Dispersion from Sparse Sensor Observations with Gappy POD Method

Energies ◽

10.3390/en13081956 ◽

2020 ◽

Vol 13 (8) ◽

pp. 1956 ◽

Cited By ~ 2

Author(s):

Zheming Tong ◽

Yue Li

Keyword(s):

Real Time ◽

Field Data ◽

Complex Geometry ◽

Sensor Placement ◽

Three Dimensional ◽

Time Estimation ◽

Sensor Data ◽

Real Time Control ◽

Time Control ◽

Gappy Pod

Real-time estimation of three-dimensional field data for enclosed spaces is critical to HVAC control. This task is challenging, especially for large enclosed spaces with complex geometry, due to the nonuniform distribution and nonlinear variations of many environmental variables. Moreover, constructing and maintaining a network of sensors to fully cover the entire space is very costly, and insufficient sensor data might deteriorate system performance. Facing such a dilemma, gappy proper orthogonal decomposition (POD) offers a solution to provide three-dimensional field data with a limited number of sensor measurements. In this study, a gappy POD method for real-time reconstruction of contaminant distribution in an enclosed space is proposed by combining the POD method with a limited number of sensor measurements. To evaluate the gappy POD method, a computational fluid dynamics (CFD) model is utilized to perform a numerical simulation to validate the effectiveness of the gappy POD method in reconstructing contaminant distributions. In addition, the optimal sensor placement is given based on a quantitative metric to maximize the reconstruction accuracy, and the sensor placement constraints are also considered during the sensor design process. The gappy POD method is found to yield accurate reconstruction results. Further works will include the implementation of real-time control based on the POD method.

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Wind-Driven Hydrodynamics in the Shallow, Micro-Tidal Estuary at the Fangar Bay (Ebro Delta, NW Mediterranean Sea)

Applied Sciences ◽

10.3390/app10196952 ◽

2020 ◽

Vol 10 (19) ◽

pp. 6952

Author(s):

Marta F-Pedrera Balsells ◽

Manel Grifoll ◽

Manuel Espino ◽

Pablo Cerralbo ◽

Agustín Sánchez-Arcilla

Keyword(s):

Numerical Experiments ◽

Field Data ◽

Three Dimensional ◽

Estuarine Circulation ◽

Water Circulation ◽

Ebro Delta ◽

Small Scale ◽

Strong Wind ◽

Axially Symmetric ◽

Nw Mediterranean

This article investigates water circulation in small-scale (~10 km2), shallow (less than 4 m) and micro-tidal estuaries. The research characterizes the hydrodynamic wind response in these domains using field data from Fangar Bay (Ebro Delta) jointly with three-dimensional numerical experiments in an idealized domain. During calm periods, field data in Fangar Bay show complex water circulation in the inner part of the estuary owing to its shallow depths and positive estuarine circulation in the mouth. Numerical experiments are conducted to investigate wind-induced water circulation due to laterally varying bathymetry. For intense up-bay wind conditions (wind intensities greater than 9 m·s−1), an axially symmetric transverse structure occurs with outflow in the central channel axis and inflow in the lateral shallow areas. These numerical results explain the water circulation observed in Fangar Bay during strong wind episodes, highlighting the role of the bathymetry in a small-scale environment. During these episodes, the water column tends to homogenize rapidly in Fangar Bay, breaking the stratification and disrupting estuarine circulation, consistent with other observations in similar domains.

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Three‐dimensional seismic exploration—A cost‐effective approach

Geophysics ◽

10.1190/1.1442710 ◽

1989 ◽

Vol 54 (7) ◽

pp. 815-823

Author(s):

F. M. Peterson ◽

W. C. Reynish

Keyword(s):

Data Processing ◽

Field Data ◽

Three Dimensional ◽

Cost Effective ◽

Seismic Exploration ◽

Effective Solution ◽

Total Cost ◽

Oil Companies ◽

Cost Effective Approach ◽

Data Field

Three‐dimensional (3-D) seismic prospecting is generally perceived as a very expensive tool that is not suitable for use by other than major oil companies or for the solution of conventional exploration geophysics problems. We illustrate how 3-D techniques were used to provide a very cost‐effective solution to a specific exploration project. A basic geologic and historical seismic outline establishes the economic and environmental framework for the survey. Drilling results and comparisons with conventional data illustrate the effectiveness of the 3-D approach. This survey was carried out during February of 1982 in the Black Creek basin of northwestern Alberta. Prolific and abundant Devonian Keg River pinnacle reefs with reserves in the 0.2 to 100 million barrel recoverable categories provide the exploration target. A prospective area of approximately [Formula: see text] was covered with a 165 ft subsurface grid of 1200 percent CDP data. Field data were acquired with a conventional 96-trace dynamite crew using a rolling, crossed‐array technique. Data processing was carried out with a flexible, conventional seismic processing package, including wavelet deconvolution, surface‐consistent statics, 3-D migration, and geologic slice displays. Total cost of the survey was $50,000 Canadian per sq mi. This paper demonstrates the interpretive power of 3-D surveys.

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Three-dimensional deformation and strain induced by municipal pumping, part 1: Analysis of field data

Journal of Hydrology ◽

10.1016/j.jhydrol.2005.06.028 ◽

2006 ◽

Vol 319 (1-4) ◽

pp. 123-142 ◽

Cited By ~ 31

Author(s):

Thomas J. Burbey ◽

Sandy M. Warner ◽

Geoff Blewitt ◽

John W. Bell ◽

Emma Hill

Keyword(s):

Field Data ◽

Three Dimensional

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Toward a three‐dimensional automatic interpretation of potential field data via generalized Hilbert transforms: Fundamental relations

Geophysics ◽

10.1190/1.1441706 ◽

1984 ◽

Vol 49 (6) ◽

pp. 780-786 ◽

Cited By ~ 279

Author(s):

Misac N. Nabighian

Keyword(s):

Hilbert Transform ◽

Potential Field ◽

Field Data ◽

Three Dimensional ◽

Analytic Signal ◽

Three Dimensions ◽

Hilbert Transforms ◽

Potential Field Data ◽

Automatic Interpretation ◽

The Hilbert Transform

The paper extends to three dimensions (3-D) the two‐dimensional (2-D) Hilbert transform relations between potential field components. For the 3-D case, it is shown that the Hilbert transform is composed of two parts, with one part acting on the X component and one part on the Y component. As for the previously developed 2-D case, it is shown that in 3-D the vertical and horizontal derivatives are the Hilbert transforms of each other. The 2-D Cauchy‐Riemann relations between a potential function and its Hilbert transform are generalized for the 3-D case. Finally, the previously developed concept of analytic signal in 2-D can be extended to 3-D as a first step toward the development of an automatic interpretation technique for potential field data.

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