Remote sensing, SWIR, Raman and XRD applications in Pesovets epithermal system mapping, Panagyurishte ore district, Bulgaria

Remote sensing UAV based study combined with field mapping, SWIR, XRD Raman and XRF tests for mineral detection outlined advanced argillic alteration domains in the Pesovets silica cap to demonstrate quick approach for epithermal gold exploration targeting and evaluation. As and Ti increasing trend toward epithermal high-sulphidation Cu-Au mineralization could be employed as a proximal path finder.

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HYDROTHERMAL ALTERATION AND MINERALIZATION OF THE PETROTA EPITHERMAL SYSTEMS (W.THRACE, GREECE)

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.16687 ◽

2004 ◽

Vol 36 (1) ◽

pp. 369 ◽

Cited By ~ 2

Author(s):

Κ. Μιχαήλ ◽

Μ. Δημήτρουλα

Keyword(s):

Hydrothermal Alteration ◽

Hydrothermal Systems ◽

Alteration Zones ◽

Epithermal System ◽

Argillic Alteration ◽

Ore Mineralization ◽

System 2 ◽

Advanced Argillic Alteration ◽

Hydrothermal Alteration Zones ◽

Host Rocks

At the Petrota graben important epithermal zones are developed. On the basis of the mineral assemblages of alteration zones and the type of the host rocks, the epithermal zones can be grouped into three epithermal systems: 1. Perama epithermal system 2. Mavrokoryfi epithermal system and 3. Othondoto epithermal system Hydrothermal alteration zones are developed within volcanoclastic rocks - epiclastic sandstones, andésite tuffs (Perama epithermal system), hyaloclastites (Mavrokoryfi) and rhyolitic rocks (Othondoto). Silicification (in various types) and advanced argillic alteration are the most important alteration zones and are established on the largest scale. Ore mineralisation occurs as veins, veinlets in silicification zones or secondary mineralisation in the supergene zone (Perama epithermal system). Disseminated ore mineralization is also found in the silicification zone at Othondoto and Mavrokoryfi epithermal systems. Based on the geological environment, the type of hydrothemal alteration zones (silicification and advanced argillic alteration) and the mineral compositon of the ore (enargite- luzonite), the hydrothermal systems of Petrota graben can be referred as high sulfidation systems.

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Chapter 22: Gold Deposits of the Yanacocha District, Cajamarca, Peru

10.5382/sp.23.22 ◽

2020 ◽

pp. 451-465

Author(s):

Richard Pilco ◽

Sean McCann

Keyword(s):

Joint Venture ◽

Volcanic Rocks ◽

Gold Deposits ◽

Epithermal Gold ◽

Sulfide Deposits ◽

High Sulfidation ◽

Significant Potential ◽

Argillic Alteration ◽

Northern Peru ◽

Advanced Argillic Alteration

Abstract The Yanacocha district of northern Peru has produced >37 million ounces (Moz) Au since production commenced in 1993. Recognized as one of the world’s most prolific high-sulfidation epithermal gold districts, its discovery was made over a four-year period (1984–1988) through a joint venture alliance operated by Newmont Corporation. Over the past 30 years the geologic understanding of the district has been enhanced by research and documentation by many academic and Newmont geoscientists. The gold deposits are hosted within Tertiary volcanic rocks consisting of pyroclastic sequences cut by several generations of breccias and intrusions, all of which have undergone silicic and advanced argillic alteration. A dominant NE-trending structural corridor bounds all deposits in the district, and local northwest fault intersections with this trend are complimentary controls on mineralization. There are 12 major deposits discovered and exploited at Yanacocha. The largest, Cerro Yanacocha, has produced >17.5 Moz Au, whereas the newest deposit to be delineated, Antonio, has a >1.0 Moz resource. The depletion of shallow, supergene-oxidized deposits has necessitated the current underground development to exploit deeper sulfide deposits. Significant potential remains within the Yanacocha district in both oxide and sulfide deposits, and ongoing exploration efforts, are leveraging learnings from mined deposits and advances in exploration technologies and tools to extend the mine life.

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Comparison of Different Algorithms to Map Hydrothermal Alteration Zones Using ASTER Remote Sensing Data for Polymetallic Vein-Type Ore Exploration: Toroud–Chahshirin Magmatic Belt (TCMB), North Iran

Remote Sensing ◽

10.3390/rs11050495 ◽

2019 ◽

Vol 11 (5) ◽

pp. 495 ◽

Cited By ~ 19

Author(s):

Lida Noori ◽

Amin Pour ◽

Ghasem Askari ◽

Nader Taghipour ◽

Biswajeet Pradhan ◽

...

Keyword(s):

Remote Sensing ◽

Hydrothermal Alteration ◽

Remote Sensing Data ◽

Base Metals ◽

Argillic Alteration ◽

Mineral Assemblages ◽

Vein Type ◽

North Of Iran ◽

Advanced Argillic Alteration ◽

Hydrothermal Alteration Zones

Polymetallic vein-type ores are important sources of precious metal and a principal type of orebody for various base-metals. In this research, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) remote sensing data were used for mapping hydrothermal alteration zones associated with epithermal polymetallic vein-type mineralization in the Toroud–Chahshirin Magmatic Belt (TCMB), North of Iran. The TCMB is the largest known goldfield and base metals province in the central-north of Iran. Propylitic, phyllic, argillic, and advanced argillic alteration and silicification zones are typically associated with Au-Cu, Ag, and/or Pb-Zn mineralization in the TCMB. Specialized image processing techniques, namely Selective Principal Component Analysis (SPCA), Band Ratio Matrix Transformation (BRMT), Spectral Angle Mapper (SAM) and Mixture Tuned Matched Filtering (MTMF) were implemented and compared to map hydrothermal alteration minerals at the pixel and sub-pixel levels. Subtle differences between altered and non-altered rocks and hydrothermal alteration mineral assemblages were detected and mapped in the study area. The SPCA and BRMT spectral transformation algorithms discriminated the propylitic, phyllic, argillic and advanced argillic alteration and silicification zones as well as lithological units. The SAM and MTMF spectral mapping algorithms detected spectrally dominated mineral groups such as muscovite/montmorillonite/illite, hematite/jarosite, and chlorite/epidote/calcite mineral assemblages, systematically. Comprehensive fieldwork and laboratory analysis, including X-ray diffraction (XRD), petrographic study, and spectroscopy were conducted in the study area for verifying the remote sensing outputs. Results indicate several high potential zones of epithermal polymetallic vein-type mineralization in the northeastern and southwestern parts of the study area, which can be considered for future systematic exploration programs. The approach used in this research has great implications for the exploration of epithermal polymetallic vein-type mineralization in other base metals provinces in Iran and semi-arid regions around the world.

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Hydrothermal corundum, topaz, diaspore and alunite supergroup minerals in the advanced argillic alteration lithocap of the Kassiteres-Sapes porphyry-epithermal system, western Thrace, Greece

Neues Jahrbuch für Mineralogie - Abhandlungen Journal of Mineralogy and Geochemistry ◽

10.1127/0077-7757/2014/0251 ◽

2014 ◽

Vol 191 (2) ◽

pp. 117-136 ◽

Cited By ~ 5

Author(s):

Panagiotis C. Voudouris

Keyword(s):

Epithermal System ◽

Argillic Alteration ◽

Advanced Argillic Alteration

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Extraction of Altered Mineral from Remote Sensing Data in Gold Exploration Based on the Nonlinear Analysis Technology

2018 10th IAPR Workshop on Pattern Recognition in Remote Sensing (PRRS) ◽

10.1109/prrs.2018.8486248 ◽

2018 ◽

Author(s):

Han Haihui ◽

Wang Yilin ◽

Zhang Zhuan ◽

Ren Guangli ◽

Yang Min

Keyword(s):

Remote Sensing ◽

Nonlinear Analysis ◽

Remote Sensing Data ◽

Sensing Data ◽

Gold Exploration

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The Land of Britain, 1930-1990: A Comparative Study of Field Mapping and Remote Sensing Techniques

Geographical Journal ◽

10.2307/3060075 ◽

1994 ◽

Vol 160 (2) ◽

pp. 173 ◽

Cited By ~ 12

Author(s):

R.M. Fuller ◽

J. Sheail ◽

C.J. Barr

Keyword(s):

Remote Sensing ◽

Comparative Study ◽

Field Mapping ◽

Remote Sensing Techniques

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The alternation haloes as the main target of epithermal gold exploration

55th EAEG Meeting ◽

10.3997/2214-4609.201411564 ◽

1993 ◽

Author(s):

R. Kontarovich ◽

E. Ruderman ◽

E. Ostrovskij ◽

V. Golubkov ◽

G. Chernjak ◽

...

Keyword(s):

Epithermal Gold ◽

Gold Exploration ◽

Main Target

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A Remote Sensing-Based Application of Bayesian Networks for Epithermal Gold Potential Mapping in Ahar-Arasbaran Area, NW Iran

Remote Sensing ◽

10.3390/rs12010105 ◽

2019 ◽

Vol 12 (1) ◽

pp. 105 ◽

Cited By ~ 9

Author(s):

Seyed Mohammad Bolouki ◽

Hamid Reza Ramazi ◽

Abbas Maghsoudi ◽

Amin Beiranvand Pour ◽

Ghahraman Sohrabi

Keyword(s):

Remote Sensing ◽

Bayesian Network ◽

Hydrothermal Alteration ◽

Gold Mineralization ◽

Epithermal Gold ◽

Alteration Zones ◽

Mineral Potential ◽

Potential Map ◽

Bayesian Network Classifier ◽

Hydrothermal Alteration Zones

Mapping hydrothermal alteration minerals using multispectral remote sensing satellite imagery provides vital information for the exploration of porphyry and epithermal ore mineralizations. The Ahar-Arasbaran region, NW Iran, contains a variety of porphyry, skarn and epithermal ore deposits. Gold mineralization occurs in the form of epithermal veins and veinlets, which is associated with hydrothermal alteration zones. Thus, the identification of hydrothermal alteration zones is one of the key indicators for targeting new prospective zones of epithermal gold mineralization in the Ahar-Arasbaran region. In this study, Landsat Enhanced Thematic Mapper+ (Landsat-7 ETM+), Landsat-8 and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) multispectral remote sensing datasets were processed to detect hydrothermal alteration zones associated with epithermal gold mineralization in the Ahar-Arasbaran region. Band ratio techniques and principal component analysis (PCA) were applied on Landsat-7 ETM+ and Landsat-8 data to map hydrothermal alteration zones. Advanced argillic, argillic-phyllic, propylitic and hydrous silica alteration zones were detected and discriminated by implementing band ratio, relative absorption band depth (RBD) and selective PCA to ASTER data. Subsequently, the Bayesian network classifier was used to synthesize the thematic layers of hydrothermal alteration zones. A mineral potential map was generated by the Bayesian network classifier, which shows several new prospective zones of epithermal gold mineralization in the Ahar-Arasbaran region. Besides, comprehensive field surveying and laboratory analysis were conducted to verify the remote sensing results and mineral potential map produced by the Bayesian network classifier. A good rate of agreement with field and laboratory data is achieved for remote sensing results and consequential mineral potential map. It is recommended that the Bayesian network classifier can be broadly used as a valuable model for fusing multi-sensor remote sensing results to generate mineral potential map for reconnaissance stages of epithermal gold exploration in the Ahar-Arasbaran region and other analogous metallogenic provinces around the world.

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