THE ROLE OF BLACK-SHALE STRATA IN THE FORMATION OF THE NATALKA AND PAVLIK GOLD DEPOSITS (Yana-Kolyma orogenic belt)

The experience of LA—ICP determining of the isotopic composition of sulfur pyrite and arsenopyrite of gold deposits of the Baikal-patomsky plateau is considered. The technique is characterized. It is shown that all the studied samples have values δ34S and δ33S strictly corresponding to the law of mass-dependent fractionation of sulfur isotopes. A regular alleviation of the isotopic composition of sulfur of pyrite as its crystals grow for Sukhoi Log and the isotopic homogeneity of pyrite and pyrrhotite of the Golets Vysokhashiy deposit are established. It is concluded that the possible role of metamorphism of the Mamsko-Oronsky belt in the formation of isotopic homogeneity of ore sulfides.

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The geochemistry, origin, and role of carbon dioxide, water, sulfur, and boron in the Yellowknife gold deposits, Northwest Territories, Canada

Economic Geology ◽

10.2113/gsecongeo.54.8.1506 ◽

1959 ◽

Vol 54 (8) ◽

pp. 1506-1524 ◽

Cited By ~ 12

Author(s):

Robert William Boyle

Keyword(s):

Carbon Dioxide ◽

Northwest Territories ◽

Gold Deposits

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Biotransformation of Metalloporphyrins by Microorganisms Isolated from Organic-Rich Metal-Bearing Black Shale

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.71-73.709 ◽

2009 ◽

Vol 71-73 ◽

pp. 709-712 ◽

Cited By ~ 1

Author(s):

Renata Matlakowska ◽

Aleksandra Sklodowska

Keyword(s):

Carbon Source ◽

Black Shale ◽

Bacterial Cells ◽

Indigenous Microorganisms ◽

Copper Tailings ◽

Naturally Occurring ◽

Laboratory Cultures ◽

Potential Use ◽

Sole Energy

Indigenous microorganisms isolated from organic-rich copper-bearing black shale from the Fore-Sudetic Monocline were able to transform naturally occurring metalloporphyrins in laboratory cultures. It was also demonstrated that these bacteria can utilize synthetic metalloporphyrins as the sole energy and carbon source. The first step in metalloporphyrin biotransformation was identified as the highly effective bioaccumulation of these compounds in bacterial cells. The ability of both living and dead cells to biosorb metalloporphyrins was also confirmed. Besides contributing to the important biogeochemical role of these microorganisms in the environment, their biotransformation activities are of potential use in the bioremediation of copper tailings as well as in the recovery of metals from organic-rich black shale ore, which is not possible using traditional hydrometallurgical procedures.

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Genesis of Carbonate Breccia Containing Invisible Gold in Taebaeksan Basin, South Korea

Minerals ◽

10.3390/min10121087 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1087

Author(s):

Sang-Gun No ◽

Maeng-Eon Park ◽

Bong-Chul Yoo ◽

Seung-Han Lee

Keyword(s):

South Korea ◽

Carbonate Rock ◽

Gold Deposits ◽

Invisible Gold ◽

Gold Particles ◽

X Ray ◽

Taebaeksan Basin ◽

The Matrix ◽

Backscattered Electron

The Yemi breccia developed and is distributed within the Paleozoic carbonate rock (Maggol Formation) in the central part of the Taebaeksan Basin, South Korea. Explanation for the genesis of the Yemi breccia has been controversial. We investigated the petrological and mineralogical properties of the breccia and the matrix materials at 60 outcrops. The Yemi breccia is divided into crackle, mosaic, and chaotic breccias based on morphology. In addition, these are divided into blackish, reddish, grayish, and white to pinkish matrix breccias according to the materials of the matrix. Quartz, calcite, pyrite, hematite (after pyrite), and minor epidote, chlorite, and opaque materials mainly comprise the matrix materials. The pyrite grains from the Yemi breccia can be divided into two types based on the mineral texture: diagenetic and hydrothermal. We analyzed the chemistry of pyrite and hematite (after pyrite) from the Yemi breccia with an electron probe X-ray microanalyzer (EPMA). Invisible gold was detected within the pyrite grains by EPMA and disseminated micron-sized isolated gold particles were discovered by backscattered electron (BSE) images. The texture of Au-bearing pyrite and gold particles in the Yemi breccia is especially well matched with pyrite and gold from the Shuiyindong Carlin-type hydrothermal gold deposits, China. Therefore, we suggest an important role of hydrothermal fluid in karstification within the Paleozoic carbonate rock.

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Modelling Seismically Induced Mesothermal Goldfields along the Deep-Rooted Cadillac-Larder Lake Fault, Abitibi, Canada

Geofluids ◽

10.1155/2018/9479528 ◽

2018 ◽

Vol 2018 ◽

pp. 1-21 ◽

Cited By ~ 1

Author(s):

Pierre Bedeaux ◽

Silvain Rafini ◽

Pierre Pilote ◽

Réal Daigneault

Keyword(s):

Gold Deposits ◽

Hydrothermal Systems ◽

High Potential ◽

Seismic Events ◽

Two Dimensional ◽

Ore Formation ◽

Predictive Mapping ◽

Geological Constraints ◽

Structural Heterogeneities

Gold deposits are not uniformly distributed along major faults due to complex (and long-debated) interactions between seismicity, hydrothermalism, and structural heterogeneities. Here, we use static stress modelling (SSM) to quantitatively investigate these interactions, by exploring the role of Cadillac-Larder Lake Fault (CLLF) Archean seismicity in the genesis of the regional goldfields. Various rheological factors are evaluated for optimizing the models’ ability to reproduce known gold occurrences, regarded as the fossil primary markers of synkinematic hydrothermal systems. We propose that the marked structural heterogeneities of the CLLF induced persistent seismic segmentation and recurrent ruptures of the same fault windows that arrested on robust node points. These ruptures favour repeated occurrences of seismically triggered hydrothermalism along long-existing fluid pathways having an enhanced permeability and iterative ore formation into supracrustal discharge zones by means of episodic drops and build-ups of pressure. Two-dimensional SSM permits the predictive mapping of these high-potential zones. These modelled zones correlate positively with the actual observed gold distribution. We demonstrate that (1) the ruptures along the Joannes Segment arresting on the Davidson Fault and Lapa’s bend can explain the occurrence and location of the Rouyn and Malartic goldfields; (2) the models’ validity is improved by implementing regional geological constraints; and (3) the distant gold occurrences from the CLLF, including the Bourlamaque field, can be explained by doublet seismic events along the Rivière-Héva and Lapause subsidiary faults. Our results provide new perspectives from a fundamental standpoint and for exploration purposes.

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