Three‐dimensional numerical analysis of downhole applied potential methods: volcanogenic massive sulphide example, Golden Grove, Western Australia

2003 ◽  
Author(s):  
Hashim Carey ◽  
Graham Heinson ◽  
Mike Sexton
Keyword(s):  
Numerical Analysis ◽  
Western Australia ◽  
Three Dimensional ◽  
Massive Sulphide ◽  
Applied Potential ◽  
Volcanogenic Massive Sulphide ◽  
Potential Methods

Reprocessing legacy three-dimensional seismic data from the Halfmile Lake and Brunswick No. 6 volcanogenic massive sulphide deposits, New Brunswick, Canada

2019 ◽  
Vol 56 (5) ◽  
pp. 569-583 ◽  
Author(s):  
Gilles Bellefleur ◽  
Saeid Cheraghi ◽  
Alireza Malehmir
Keyword(s):  
New Brunswick ◽  
Seismic Data ◽  
Three Dimensional ◽  
Massive Sulphide ◽  
Seismic Survey ◽  
Deep Zone ◽  
3D Seismic ◽  
Massive Sulphide Deposits ◽  
Volcanogenic Massive Sulphide ◽  
Sulphide Deposits

We reprocessed legacy three-dimensional (3D) seismic data from the Halfmile Lake and Brunswick areas, both of which were acquired for mineral exploration in the Bathurst Mining Camp, New Brunswick. Each 3D seismic survey was acquired over known volcanogenic massive sulphide deposits and covered areas with strong mineral potential. Most improvements resulted from a reduction of coherent and random noise on prestack gathers and from an improved velocity model, combined with re-imaging with dip moveout corrections and poststack migration or prestack time migration. At Halfmile Lake, the new imaging results show the Deep zone and a possible extension of the sulphide mineralization at greater depth. True amplitude processing has shown that this anomaly has strong amplitudes and is offset from the Deep zone by a shallowly dipping fault (<15°). With the clearer geological context provided by our results, this anomaly, which appears as a stand-alone anomaly on an original image obtained by Noranda Exploration Ltd., becomes a defendable exploration target. Nonorthogonal acquisition geometry and receiver patches of the Brunswick No. 6 3D seismic survey generated artefacts after dip moveout processing that reduced the overall quality of the seismic volumes. By using a filtering approach based on the application of a weighted Laplacian-Gaussian filter in the Kx–Ky domain, we reduced the noise and improved the continuity of reflections. We also imaged the short and flat reflections observed previously only in the shallow part of prestack time migrated data. These short reflections appear as diffractions on the filtered stacked section with dip moveout corrections, indicating that they originate from small geological bodies or discontinuities in the subsurface.

scholarly journals Three-dimensional stochastic assimilation of gravity data in Lalor volcanogenic massive sulphide, Manitoba, Canada

2019 ◽  
Vol 56 (5) ◽  
pp. 556-568
Author(s):  
Shiva Tirdad ◽  
Erwan Gloaguen ◽  
Abderezzak Bouchedda ◽  
J. Christian Dupuis
Keyword(s):  
Conceptual Model ◽  
Gravity Data ◽  
Bouguer Anomaly ◽  
Three Dimensional ◽  
Massive Sulphide ◽  
Sequential Gaussian Simulation ◽  
Multiple Point ◽  
Deformation Method ◽  
Geological Unit ◽  
Volcanogenic Massive Sulphide

We propose a new numerical workflow based on stochastic data integration where we merge a conceptual geological model, drillhole geophysical and geological logs, and surface geophysical data to compute a unified numerical model of a volcanogenic massive sulphide (VMS) deposit. The first step of the workflow consists in building a three-dimensional (3D) numerical conceptual model of the geology. This conceptual model, as well as geological logs, is then used to generate multiple equiprobable scenarios of the geology by means of multiple-point simulation (MPS). The MPS method studies high-order statistics in the space of a numerical conceptual model, making it possible to reproduce complex geological structures. We then use conventional conditional sequential Gaussian simulation, which is a method based on a node-by-node sequential process, to stochastically populate the geological grid with densities. For this purpose we use available density logs to simulate multiple equiprobable spatial distributions of the density at high spatial resolution within each geological unit separately. The stochastic high-resolution density models are iteratively combined by the gradual deformation method to minimize the difference between measured Bouguer anomaly data and the data computed on the combined realizations of density. Application of the proposed method to the Lalor deposit, a VMS deposit in Manitoba, Canada, produces a density model that honours the geology of the deposit and the Bouguer anomaly data. This unified model has the advantage to include all the available information (geological and density logs and surface geophysics) at scales appropriate for mining applications.

Hydrothermal alteration and lithogeochemistry of the Boundary volcanogenic massive sulphide deposit, central Newfoundland, Canada

2016 ◽  
Vol 53 (5) ◽  
pp. 506-527 ◽  
Author(s):  
Michael J. Buschette ◽  
Stephen J. Piercey
Keyword(s):  
Hydrothermal Alteration ◽  
Three Dimensional ◽  
Mobile Element ◽  
Short Wave ◽  
Massive Sulphide ◽  
Massive Sulphide Deposit ◽  
Sulphide Deposit ◽  
Element Geochemistry ◽  
Volcanogenic Massive Sulphide ◽  
Short Wave Infrared

The Boundary volcanogenic massive sulphide deposit (0.50 Mt at 3.5% Cu, 4.0% Zn, and 1.0% Pb, 34 g/t Ag) is hosted by the Tally Pond group (∼510 Ma), Victoria Lake supergroup, central Newfoundland, Canada, and represents a subseafloor replacement-style massive sulphide deposit. The deposit is hosted by rhyolitic lapilli tuff of the Bindons Pond formation. The rhyolites have immobile element signatures consistent with the formation of felsic rocks through the melting of juvenile-weakly evolved crust within an extensional rift environment (rifted peri-continental arc). The host rocks of the Boundary deposit contain elevated alteration indices, including high Ba/Sr, Hg/Na2O, chlorite–carbonate–pyrite index, and Ishikawa alteration index values. The mobile element geochemistry effectively differentiates between three distinct hydrothermal alteration styles: intense chlorite, chlorite-sericite, and quartz-sericite. Intense chlorite alteration exhibits mass gains in MgO and Cu and depletions in K2O and Ba. Chlorite-sericite alteration contains variable gains and losses of SiO2, K2O, Ba, MgO, and Fe2O3 depending on the dominant matrix mineral phase (i.e., chlorite vs. sericite). The quartz-sericite assemblage has mass gains in SiO2, K2O, Ba, and Fe2O3. Short-wave infrared spectroscopic data, particularly AlOH and FeOH absorption hulls, differentiate alteration styles and correlate with lithogeochemical results: AlOH absorption features increase in length (>2208 nm) proximal to Zn mineralization and wavelength variations correspond to relative abundances of sericite and chlorite. Electron probe microanalyses indicate that increasing short-wave infrared wavelengths correlate with increasing Mg–Fe and Fe contents in sericite and chlorite, respectively. Collectively, these data have been used to develop a three-dimensional alteration model of the Boundary deposit.

Three dimensional numerical analysis of heat transfer during spray quenching of 22MnB5 steel with a single nozzle

2020 ◽  
Author(s):  
Emre Bulut ◽  
Gökhan Sevilgen ◽  
Ferdi Eşiyok ◽  
Ferruh Öztürk ◽  
Tuğçe Turan Abi
Keyword(s):  
Heat Transfer ◽  
Numerical Analysis ◽  
Three Dimensional ◽  
22Mnb5 Steel

Optimization of the Navy’s three-dimensional mine impact burial prediction simulation model, Impact35, using high-order numerical methods

2021 ◽  
pp. 154851292110286
Author(s):  
Athanasios Donas ◽  
Ioannis Famelis ◽  
Peter C Chu ◽  
George Galanis
Keyword(s):  
Numerical Analysis ◽  
Numerical Methods ◽  
Prediction Model ◽  
Simulation Model ◽  
Three Dimensional ◽  
Simulation System ◽  
High Order ◽  
Alternative Methodology ◽  
Runge Kutta ◽  
Fifth Order

The aim of this paper is to present an application of high-order numerical analysis methods to a simulation system that models the movement of a cylindrical-shaped object (mine, projectile, etc.) in a marine environment and in general in fluids with important applications in Naval operations. More specifically, an alternative methodology is proposed for the dynamics of the Navy’s three-dimensional mine impact burial prediction model, Impact35/vortex, based on the Dormand–Prince Runge–Kutta fifth-order and the singly diagonally implicit Runge–Kutta fifth-order methods. The main aim is to improve the time efficiency of the system, while keeping the deviation levels of the final results, derived from the standard and the proposed methodology, low.

scholarly journals Air Ventilation Performance of School Classrooms with Respect to the Installation Positions of Return Duct

2021 ◽  
Vol 13 (11) ◽  
pp. 6188
Author(s):  
Sungwan Son ◽  
Choon-Man Jang
Keyword(s):  
Air Quality ◽  
Numerical Analysis ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Three Dimensional ◽  
Cross Infection ◽  
School Students ◽  
Height Range ◽  
Air Ventilation ◽  
Ventilation Performance

For students, who spend most of their time in school classrooms, it is important to maintain indoor air quality (IAQ) to ensure a comfortable and healthy life. Recently, the ventilation performance for indoor air quality in elementary schools has emerged as an important social issue due to the increase in the number of days of continuous high concentrations of particulate matter. Three-dimensional numerical analysis has been introduced to evaluate the indoor airflow according to the installation location of return diffusers. Considering the possibility of the cross-infection of infectious diseases between students due to the direction of airflow in the classroom, the airflow angles of the average respiratory height range of elementary school students, between 1.0 and 1.5 m, are analyzed. Throughout the numerical analysis inside the classroom, it is found that the floor return system reduces the indoor horizontal airflow that causes cross-infection among students by 20% compared to the upper return systems. Air ventilation performance is also analyzed in detail using the results of numerical simulation, including streamlines, temperature and the age of air.

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