THE 3D TRANSIENT ELECTROMAGNETIC FORWARD MODELING OF VOLCANOGENIC MASSIVE SULFIDE ORE DEPOSITS

2016 ◽  
Vol 59 (6) ◽  
pp. 725-733 ◽  
Author(s):  
LI Rui-Xue ◽  
WANG He ◽  
XI Zhen-Zhu ◽  
LONG Xia ◽  
HOU Hai-Tao ◽  
...  
Keyword(s):  
Forward Modeling ◽  
Massive Sulfide ◽  
Ore Deposits ◽  
Volcanogenic Massive Sulfide ◽  
Transient Electromagnetic ◽  
Sulfide Ore

scholarly journals U-Th-He Geochronology of Pyrite from the Uzelga VMS Deposit (South Urals)—New Perspectives for Direct Dating of the Ore-Forming Processes

Minerals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 629
Author(s):  
Olga Yakubovich ◽  
Mary Podolskaya ◽  
Ilya Vikentyev ◽  
Elena Fokina ◽  
Alexander Kotov
Keyword(s):  
Methodological Approach ◽  
Massive Sulfide ◽  
Ore Deposits ◽  
South Urals ◽  
Volcanogenic Massive Sulfide ◽  
Ore Formation ◽  
Relative Simplicity ◽  
Facies Metamorphism ◽  
Thermal Extraction ◽  
Pyrite Sample

We report on the application of the U-Th-He method for the direct dating of pyrite and provide an original methodological approach for measurement of U, Th and He in single grains without loss of parent nuclides during thermal extraction of He. The U-Th-He age of ten samples of high-crystalline stoichiometric pyrite from unoxidized massive ores of the Uzelga volcanogenic massive sulfide (VMS) deposit, South Urals, is 382 ± 12 Ma (2σ) (U concentrations ~1–5 ppm; 4He ~10−4 cm3 STP g−1). This age is consistent with independent (biostratigraphic) estimations of the age of ore formation (ca, 389–380 Ma) and is remarkably older than the probable age of the regional prehnite-pumpellyite facies metamorphism (~340–345 Ma). Our results indicate that the U-Th-He dating of ~1 mg weight pyrite sample is possible and open new perspectives for the dating of ore deposits. The relative simplicity of U-Th-He dating in comparison with other geochronological methods makes this approach interesting for further application.

3D seismic imaging of volcanogenic massive sulfide deposits in the Flin Flon mining camp, Canada: Part 2 — Forward modeling

Geophysics ◽  
2012 ◽  
Vol 77 (5) ◽  
pp. WC81-WC93 ◽  
Author(s):  
Michal Malinowski ◽  
Ernst Schetselaar ◽  
Donald J. White
Keyword(s):  
Synthetic Data ◽  
Massive Sulfide ◽  
Ore Deposits ◽  
Earth Model ◽  
Seismic Modeling ◽  
Volcanogenic Massive Sulfide ◽  
Data Set ◽  
Rock Interaction ◽  
Time Migration ◽  
Flin Flon

We applied seismic modeling for a detailed 3D geologic model of the Flin Flon mining camp (Canada) to address some imaging and interpretation issues related to a [Formula: see text] 3D survey acquired in the camp and described in a complementary paper (part 1). A 3D geologic volumetric model of the camp was created based on a compilation of geologic data constraints from drillholes, surface geologic mapping, interpretation of 2D seismic profiles, and 3D surface and grid geostatistical modeling techniques. The 3D modeling methodology was based on a hierarchical approach to account for the heterogeneous spatial distribution of geologic constraints. Elastic parameters were assigned within the model based on core sample measurements and correlation with the different lithologies. The phase-screen algorithm used for seismic modeling was validated against analytic and finite-difference solutions to ensure that it provided accurate amplitude-variation-with-offset behavior for dipping strata. Synthetic data were generated to form zero-offset (stack) volume and also a complete prestack data set using the geometry of the real 3D survey. We found that the ability to detect a clear signature of the volcanogenic massive sulfide with ore deposits is dependent on the mineralization type (pyrite versus pyrrhotite rich ore), especially when ore-host rock interaction is considered. In the presence of an increasing fraction of the host rhyolite rock within the model volume, the response from the lower impedance pyrrhotite ore is masked by that of the rhyolite. Migration tests showed that poststack migration effectively enhances noisy 3D DMO data and provides comparable results to more computationally expensive prestack time migration. Amplitude anomalies identified in the original 3D data, which were not predicted by our modeling, could represent potential exploration targets in an undeveloped part of the camp, assuming that our a priori earth model is sufficiently accurate.

Performance of low-fold scalar migration for downhole seismic imaging of massive sulfide ore deposits at Norman West, Sudbury, Canada

Geophysics ◽  
2012 ◽  
Vol 77 (5) ◽  
pp. WC3-WC13 ◽  
Author(s):  
Christof Mueller ◽  
Gilles Bellefleur ◽  
Erick Adam ◽  
Gervais Perron ◽  
Marko Mah ◽  
...  
Keyword(s):  
Seismic Data ◽  
Seismic Imaging ◽  
Signal To Noise Ratio ◽  
Massive Sulfide ◽  
Ore Deposits ◽  
Ore Deposit ◽  
Seismic Scattering ◽  
Vertical Seismic Profiling ◽  
Sudbury Igneous Complex ◽  
Sulfide Ore

The Downhole Seismic Imaging consortium conducted two consecutive vertical seismic profiling surveys in the Norman West mining camp (Sudbury, Canada) in 1998 and 1999. These were aimed toward imaging a massive sulfide ore deposit situated within the footwall of the Sudbury Igneous Complex (SIC). Three-component seismic data were acquired in four boreholes with variable signal-to-noise ratio and poor polarization quality. Consequently, the images suffered from strong azimuthal ambiguity. A strike filter, passing only reflections originating from within the SIC, was applied during migration to enhance interpretability of the images obtained. Migrated images showed structures correlating with the known position of an ore deposit located 1800 m away from one borehole (N40). Diffraction coherency migration enhanced the image of the deposit, and suggested strong seismic scattering from within the footwall of the SIC.

Development of a laser ablation ICP-MS method for the analysis of fluid inclusions associated with volcanogenic massive sulfide deposits

2021 ◽  
pp. geochem2020-043
Author(s):  
Madison A. Schmidt ◽  
Matthew I. Leybourne ◽  
Jan M. Peter ◽  
Duane C. Petts ◽  
Simon E. Jackson ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Fluid Inclusions ◽  
Inductively Coupled Plasma ◽  
Massive Sulfide ◽  
Ore Deposits ◽  
Volcanogenic Massive Sulfide ◽  
Metals And Metalloids ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Vms Deposits

There is increasing acceptance of the presence of variable magmatic contributions to the mineralizing fluids in the formation of volcanogenic massive sulfide (VMS) deposits. The world-class Windy Craggy Cu-Co-Au deposit (>300 MT @ 2.12 wt.% Cu) in northwestern British Columbia is of interest because, unlike most VMS deposits, quarts fluid inclusions from within the deposit range from relatively low to intermediate salinity (most 6-16 wt.% equivalent). In this study we used an excimer (193 nm) laser ablation system interfaced to a quadrupole inductively coupled plasma mass spectrometer to quantify key metals and metalloids that are considered by many to be indicative of magmatic contributions to hydrothermal ore deposits. Although LA-ICP-MS signals from these low-salinity inclusions are highly transient, we were able to quantify Na, Mg, K, Ca, Mn, Fe, Co, Cu, Zn, Sr, Sn, Ba, Ce, Pb and Bi consistently – of the 34 elements that were monitored. Furthermore, Cl, Sb, Cd, Mo, Rb, Br, and As were also measured in a significant number of inclusions. Comparison of the fluid inclusion chemistry with unaltered and altered mafic volcanic and sedimentary rocks and mineralized samples from the deposit indicate that enrichment in the main ore metals (Cu, Zn, Fe, Pb) in the inclusions reflects that of the altered rocks and sulfides. Metals and metalloids that may indicate a magmatic contribution typically show much greater enrichments in the fluid inclusions much greater over the host rocks at the same Cu concentration; in particular Bi, Sn and Sb are significantly elevated when compared to the host rock samples. These data are consistent with the ore-forming fluids at Windy Craggy having a strong magmatic contribution.

Transient electromagnetic surveys in the Okiep district

Geophysics ◽  
1992 ◽  
Vol 57 (5) ◽  
pp. 736-744 ◽  
Author(s):  
M. J. Maher
Keyword(s):  
Time Constant ◽  
Massive Sulfide ◽  
Sulfide Mineralization ◽  
Limited Size ◽  
Modern Times ◽  
Transient Electromagnetic ◽  
Diamond Drilling ◽  
Ore Bodies ◽  
Sulfide Ore ◽  
Massive Sulfide Mineralization

In the Okiep District early miners produced massive sulfide ore from some five deposits. Some of these deposits later contributed to the reserves of disseminated ore mined during modern times. It is unreasonable to assume that all of the massive sulfide bodies present within the area are intersected by the erosion surface and thus were discovered by the early miners. Consequently, blind massive sulfide ore bodies could be present and may have large quantities of disseminated ore associated with them. The transient electromagnetic method is ideally suited to exploring for massive sulfide bodies, and six test surveys were carried out at various sites in the district. Four of these surveys were unsuccessful whereas, at the remaining two sites, excellent anomalies were recorded. At Ezelsfontein East Extension an anomaly was recorded indicative of a massive sulfide body at shallow depth and of generally flat attitude. This anomaly has a time constant of 15 ms and the interpreted body was confirmed by a limited diamond drilling program. A deep, flat‐lying conductor was interpreted from the TEM results at Fonteintjie West Prospect. This anomaly, with a time constant of 0.6 ms, has limited size. Diamond drilling confirmed the presence of submassive to massive sulfide mineralization at this locale. Neither of these two drilled prospects had economic mineralization.

A Special Issue on Archean Magmatism, Volcanism, and Ore Deposits: Part 2. Volcanogenic Massive Sulfide Deposits Preface,

2013 ◽  
Vol 109 (1) ◽  
pp. 1-9 ◽  
Author(s):  
P. Mercier-Langevin ◽  
H. L. Gibson ◽  
M. D. Hannington ◽  
J. Goutier ◽  
T. Monecke ◽  
...  
Keyword(s):  
Massive Sulfide ◽  
Ore Deposits ◽  
Special Issue ◽  
Volcanogenic Massive Sulfide ◽  
Sulfide Deposits ◽  
Massive Sulfide Deposits ◽  
Volcanogenic Massive Sulfide Deposits

Pyrite deformation textures in the massive sulfide ore deposits of the Norwegian Caledonides

2010 ◽  
Vol 483 (3-4) ◽  
pp. 269-286 ◽  
Author(s):  
Craig D. Barrie ◽  
Alan P. Boyle ◽  
Nigel J. Cook ◽  
David J. Prior
Keyword(s):  
Massive Sulfide ◽  
Ore Deposits ◽  
Sulfide Ore ◽  
Deformation Textures ◽  
Norwegian Caledonides
Sign in / Sign up

Export Citation Format

Share Document