scholarly journals Exploration of Seafloor Massive Sulfide Deposits with Fixed-Offset Marine Controlled Source Electromagnetic Method: Numerical Simulations and the Effects of Electrical Anisotropy

Minerals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 457 ◽  
Author(s):  
Ronghua Peng ◽  
Bo Han ◽  
Xiangyun Hu
Keyword(s):  
Numerical Simulations ◽  
Mineral Exploration ◽  
Data Interpretation ◽  
Massive Sulfide ◽  
Reliable Data ◽  
Electromagnetic Method ◽  
Electrical Anisotropy ◽  
Controlled Source ◽  
Marine Csem ◽  
Seafloor Massive Sulfide

Seafloor massive sulfide (SMS) deposits have attracted growing interest and become the focus of current seafloor mineral exploration. One key challenge is to delineate potential SMS accumulations and estimate their quantity and quality for prospective resource mining. Recently, geophysical electromagnetic methods which are routinely used for land-based mineral exploration are being adapted to detect and assess SMS occurrences by imaging their conductivity distributions. However, the rough seafloor topography and electrical anisotropy of the seafloor formations encountered in practical surveys pose challenges for reliable data interpretation, and recent studies have revealed that the rough bathymetry could cause measurable distortions. Here, we consider a fixed-offset marine controlled-source electromagnetic method (CSEM) for SMS exploration, and investigate the effects of electrical anisotropy of sedimentary formations through numerical simulations for marine CSEM surveys aiming at conductive targets in the shallow regions of the seafloor. Numerical results demonstrate that the presence of electrical anisotropy could impose significant influence on fixed-offset marine CSEM data and suggest that the distortions should be sufficiently accounted for reliable data interpretation, thus lending confidence to subsequent quantification of available SMS minerals.

scholarly journals Sensitivity and Resolution of Controlled-Source Electromagnetic Method for Gas Hydrate Stable Zone

Energies ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 8318
Author(s):  
Zhenwei Guo ◽  
Yunxi Yuan ◽  
Mengyuan Jiang ◽  
Jianxin Liu ◽  
Xianying Wang ◽  
...  
Keyword(s):  
Natural Gas ◽  
Gas Hydrates ◽  
Gas Hydrate ◽  
Synthetic Data ◽  
Electromagnetic Method ◽  
Natural Gas Hydrate ◽  
Controlled Source ◽  
Transverse Resistance ◽  
Marine Csem ◽  
Stable Zone

Natural gas hydrate is one of the most important clean energies and part of carbon cycle, due to the least carbon content. Natural gas hydrates depend on high pressure and low temperatures, located under seabed or permafrost. Small changes in temperature and pressure may lead gas hydrates to separate into water and gas, commonly as methane. As a powerful greenhouse gas, methane is much stronger than carbon dioxide. Therefore, it is necessary to detect the gas hydrates stable zone (GHSZ) before the methane gas escapes from GHSZ. Marine controlled source electromagnetic method (CSEM) is a useful tool to detect gas hydrate in offshore. The results from 3D CSEM method are a resistivity cube to describe the distribution of gas hydrates. In order to study the detectability of CSEM method, we simulate the sensitivity and resolution of marine CSEM synthetic data. By using the sensitivity and resolution, a simple statement may be quickly judged on the existence and occurrence range of the natural gas hydrate. In this paper, we compare the resolution of marine CSEM method with various transverse resistance. This information may help researchers find out whether the GHSZ exists or not.

Mineral exploration with 3-D controlled-source electromagnetic method: a synthetic study of Sukhoi Log gold deposit

2019 ◽  
Vol 219 (3) ◽  
pp. 1698-1716 ◽  
Author(s):  
M Malovichko ◽  
A V Tarasov ◽  
N Yavich ◽  
M S Zhdanov
Keyword(s):  
Finite Difference ◽  
Gold Deposit ◽  
Large Scale ◽  
Mineral Exploration ◽  
Mineral Deposit ◽  
Hydrocarbon Exploration ◽  
Contraction Operator ◽  
Inversion Algorithm ◽  
Controlled Source ◽  
Regularized Inversion

SUMMARY This paper presents a feasibility study of using the controlled-source frequency-domain electromagnetic (CSEM) method in mineral exploration. The method has been widely applied for offshore hydrocarbon exploration; however, nowadays this method is rarely used on land. In order to conduct this study, we have developed a fully parallelized forward modelling finite-difference (FD) code based on the iterative solver with contraction-operator preconditioner. The regularized inversion algorithm uses the Gauss–Newton method to minimize the Tikhonov parametric functional with the Laplacian-type stabilizer. A 3-D parallel inversion code, based on the iterative finite-difference solver with the contraction-operator preconditioner, has been evaluated for the solution of the large-scale inverse problems. Using the computer simulation for a synthetic model of Sukhoi Log gold deposit, we have compared the CSEM method with the conventional direct current sounding and the CSEM survey with a single remote transmitter. Our results suggest that, a properly designed electromagnetic survey together with modern 3-D inversion could provide detailed information about the geoelectrical structure of the mineral deposit.

Economic Seafloor Massive Sulfide Mining by Japan’s Model

2016 ◽  
Author(s):  
Tetsuo Yamazaki ◽  
Yosuke Takeda ◽  
Rei Arai ◽  
Naoki Nakatani
Keyword(s):  
Papua New Guinea ◽  
Waste Disposal ◽  
Mining Operation ◽  
Massive Sulfide ◽  
Sea Surface ◽  
Flexible Link ◽  
Private Companies ◽  
Mining Site ◽  
Seafloor Massive Sulfide ◽  
Disposal Cost

Because of the higher Au, Ag, and Cu contents, seafloor massive sulfides (SMS) have received much attention as future commercial mining targets by private companies and nations. One of them, Solwara 1 Project in Papua New Guinea (PNG), is scheduled to start the commercial mining operation from 2018. Because the mining site is inter-island area and almost no cost is necessary for the waste disposal in PNG, the economy of the mining is expected very well. In contrast with this, because all the SMS distribution sites in Japan locate outer ocean areas and the waste disposal cost on land in Japan is very expensive, the economy of SMS mining in Japan is quite negative. In order to overcome the problems, a self-standing riser with flexible link to the sea surface platform and a primary ore separation on the seafloor prior to the ore lift-up are proposed. The improved SMS mining concept named Japan’s model is examined.

Prediction of double stacking hydrocarbon using Marine Controlled Source Electromagnetic method

2014 ◽  
Author(s):  
Muhammad Rauf ◽  
Noorhana Yahya ◽  
Tadiwa Elisha Nyamasvisva ◽  
Adeel Ansari ◽  
Afza Shafie ◽  
...  
Keyword(s):  
Electromagnetic Method ◽  
Controlled Source

Pb-Nd-Sr Isotope Geochemistry of Metapelites from the Iberian Pyrite Belt and Its Relevance to Provenance Analysis and Mineral Exploration Surveys

2021 ◽  
Author(s):  
Filipa Luz ◽  
António Mateus ◽  
Ezequiel Ferreira ◽  
Colombo G. Tassinari ◽  
Jorge Figueiras
Keyword(s):  
Isotope Geochemistry ◽  
Mineral Exploration ◽  
Hanging Wall ◽  
Massive Sulfide ◽  
Iberian Pyrite Belt ◽  
Isotopic Signature ◽  
Sr Isotope ◽  
Provenance Analysis ◽  
Basement Rocks ◽  
World Class

Abstract The boundary in the Iberian Pyrite Belt is a world-class metallogenic district developed at the Devonian-Carboniferous boundary the Iberian Variscides that currently has seven active mines: Neves Corvo (Cu-Zn-Sn) and Aljustrel (Cu-Zn) in Portugal, and Riotinto (Cu), Las Cruces (Cu), Aguas Teñidas (Cu-Zn-Pb), Sotiel-Coronada (Cu-Zn-Pb), and La Magdalena (Cu-Zn-Pb) in Spain. The Iberian Pyrite Belt massive sulfide ores are usually hosted in the lower sections of the volcano-sedimentary complex (late Famennian to late Visean), but they also occur in the uppermost levels of the phyllite-quartzite group at the Neves Corvo deposit, stratigraphically below the volcano-sedimentary complex. A Pb-Nd-Sr isotope dataset was obtained for 98 Iberian Pyrite Belt metapelite samples (from Givetian to upper Visean), representing several phyllite-quartzite group and volcano-sedimentary complex sections that include the footwall and hanging-wall domains of ore horizons at the Neves Corvo, Aljustrel, and Lousal mines. The combination of whole-rock Nd and Sr isotopes with Th/Sc ratios shows that the siliciclastic components of Iberian Pyrite Belt metapelites are derived from older quartz-feldspathic basement rocks (–11 ≤ εNdinitial(i) ≤ –8 and (87Sr/86Sr)i up to 0.727). The younger volcano-sedimentary complex metapelites (upper Tournaisian) often comprise volcanic-derived constituents with a juvenile isotopic signature, shifting the εNdi up to +0.2. The Pb isotope data confirm that the phyllite-quartzite group and volcano-sedimentary complex successions are crustal reservoirs for metals found in the deposits. In Neves Corvo, where there is more significant Sn- and Cu-rich mineralization, the higher (206Pb/204Pb)i and (207Pb/204Pb)i values displayed by phyllite-quartzite group and lower volcano-sedimentary complex metapelites (up to 15.66 and 18.33, respectively) suggest additional contributions to the metal budget from a deeper and more radiogenic source. The proximity to Iberian Pyrite Belt massive sulfide ore systems hosted in metapelite successions is observed when (207Pb/204Pb)i >15.60 and Fe2O3/TiO2 or (Cu+Zn+Pb)/Sc >10. These are important criteria that should be considered in geochemical exploration surveys designed for the Iberian Pyrite Belt.

Complex Resistivity Method and its Application in Mineral Resource Exploration

2011 ◽  
Vol 396-398 ◽  
pp. 115-118
Author(s):  
Xin Gong Tang ◽  
Xing Bing Xie ◽  
Liang Jun Yan
Keyword(s):  
Oil And Gas ◽  
Supply And Demand ◽  
Mineral Resources ◽  
Underground Water ◽  
Electromagnetic Method ◽  
Complex Resistivity ◽  
West China ◽  
Controlled Source ◽  
Resistivity Method ◽  
Resource Exploration

Complex resistivity (CR) is one of an electromagnetic method which plays an important role in the exploration of oil and gas, underground water as well as solid mineral resources in recent years. Nowadays China is under fast developing and there is still a big gap between the supply and demand of mineral resources. As an effective controlled source electromagnetic method, CR method can be easily used to judge the content of resources, determine the target reservoir and select a favorable drilling area. In this paper, an introduction to CR method and its application in copper mine exploration in west China is present. The result shows that CR is an effective electromagnetic method in the exploration of deep mineral resources.

scholarly journals Chemical Mass Balance, Depositional Efficiency, and Rates of Formation of Seafloor Massive Sulfide Deposits

2020 ◽  
Author(s):  
John Jamieson ◽  
Dennis Sanchez Mora ◽  
Ben Peterkin ◽  
Thibaut Barreyre ◽  
Javier Escartin ◽  
...  
Keyword(s):  
Mass Balance ◽  
Massive Sulfide ◽  
Chemical Mass Balance ◽  
Sulfide Deposits ◽  
Massive Sulfide Deposits ◽  
Seafloor Massive Sulfide

scholarly journals Subseafloor Alteration of a Modern Mafic-Volcaniclastic Hosted Seafloor Massive Sulfide Deposit

2020 ◽  
Author(s):  
Melissa. O Anderson ◽  
Mark Hannington ◽  
Timothy McConachy ◽  
John Jamieson ◽  
Thor Hansteen ◽  
...  
Keyword(s):  
Massive Sulfide ◽  
Sulfide Deposit ◽  
Massive Sulfide Deposit ◽  
Seafloor Massive Sulfide
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