Geochronological, Structural, Isotopes and Fluid Inclusion Constraints of the Polymetallic Domo de Yauli District, Peru


Book Description

L'origine des gisements polymétalliques du Domo de Yauli est liée au magmatisme Miocène ayant affecté les Andes péruviennes. Cette étude met en évidence les relations géochronologiques et structurales entre les intrusions et les corps minéralisés, ainsi que les caractéristiques des fluides hydrothermaux. Les âges obtenus sur les intrusions et les minéralisations indiquent un système pulsé et répétitif durant 9 Ma, alors que les contraintes associées à la formation des gisements montrent un champ hétérogène probablement lié à l'influence de linéaments crustaux. Les rapports isotopiques de Sr, Pb, O et H associés à l'étude des inclusions fluides, par microthermométrie, spectroscopie Raman et LA-ICP-MS, révèlent l'influence d'au moins trois fluides d'origines et de caractéristiques différentes. Leur mélange a conduit à la formation des gisements, alors que les éléments économiquement intéressants ont uniquement été apportés par le fluide s'étant séparé du magma.




The Raúl-Condestable Iron Oxide Copper-gold Deposit, Central Coast of Peru


Book Description

Cette thèse de doctorat est dédiée au gisement de cuivre-or de type "iron oxide copper-gold" de Raúl-Condestable, localisé à 90 km au sud de Lima, sur la côte péruvienne. Le minerai est composé de chalcopyrite, pyrite, pyrrhorite et magnétite, sous la forme de disséminations, remplissages de porosité, remplacements et veines dans des roches amphibolitisées appartenant à une série volcanosédimentaire du Crétacé inférieur.







Economic Geology


Book Description




Hydrothermal Processes and Mineral Systems


Book Description

Hydrothermal processes on Earth have played an important role in the evolution of our planet. These processes link the lithosphere, hydrosphere and biosphere in continuously evolving dynamic systems. Terrestrial hydrothermal processes have been active since water condensed to form the hydrosphere, most probably from about 4.4 Ga. The circulation of hot aqueous solution (hydrothermal systems) at, and below, the Earth’s surface is ultimately driven by magmatic heat. This book presents an in-depth review of hydrothermal proceses and systems that form beneath the oceans and in intracontinental rifts, continental margins and magmatic arcs. The interaction of hydrothermal fluids with rockwalls, the hydrophere and the biophere, together with changes in their composition through time and space, contribute to the formation of a wide range of mineral deposit types and associated wallrock alteration. On Earth, sites of hydrothermal activity support varied ecosystems based on a range of chemotrophic microorganisms both at surface and in the subsurface. This book also provides an overview of hydrothermal systems associated with meteorite impacts and explores the possibility that hydrothermal processes operate on other terrestrial planets, such as Mars, or satellites of the outer planets such as Titan and Europa. Possible analogues of extraterrestrial putative hydrothermal processes pose the intriguing question of whether primitive life, as we know it, may exist or existed in these planetary bodies. Audience: This volume will be of interest to scientists and researchers in geosciences and life sciences departments, as well as to professionals and scientists involved in mining and mineral exploration.







Mineral Deposits at the Beginning of the 21st Century


Book Description

The Joint 6th Biennial SGA-SEG Meeting was held in Krakow in August 2001. This volume contains 274 extended abstracts, grouped thematically under 18 session titles covering topics such as lead-zinc deposits; metamorphism affecting mineral deposits; and the environmental aspects of mining.




Geological and Structural Setting, Age, and Geochemistry of the Orogenic Gold Deposits at the Pataz Province, Eastern Andean Cordillera, Peru


Book Description

La province de Pataz au Nord-Pérou est la plus septentrionale des ceintures paléozoïques d'or, antimoine et tungstène orogéniques (mésothermales) de la Cordillère Orientale des Andes Centrales. Longue de plus de 160 km, elle est connue pour ses veines épigénétiques de quartz aurifères riches en sulfures (ressource : 40 millions d'onces d'or). Les minéralisations, datées à ~314 Ma, sont localisées dans des fractures inverse-décrochantes dextres et d'extension le long des marges et à l'intérieur du batholite de Pataz (329 Ma) et dans les roches métasédimentaires avoisinantes. L'intrusion hôte n'exerce qu'un rôle passif dans leur genèse et fonctionne uniquement comme un réceptacle structural très favorable. La minéralisation est temporellement liée à un stade d'exhumation du bâti et à l'addition d'un flux de chaleur dans une croûte épaissie. Le piégeage de l'or au contact des sulfures microfracturées interviendrait à 5-10 km de profondeur par dilution d'un fluide salin précoce par des eaux superficielles.




The Geology of Ore Deposits


Book Description

Modern civilizations dependence upon an increasing volume and diversity of minerals makes the search for new ore deposits ever more difficult. Now available from Waveland Press, Guilbert & Parks text presents ideas, principles, and data fundamental for beginning economic geologists to understand the genesis and localization of ore deposits and of the minerals associated with them. The authors comprehensively describe the physical and chemical characteristics of ore deposits and correlate them with environments and conditions of deposition, since ore deposits are best interpreted as extensions of the environments responsible for their enclosing rocks. Examples and illustrations emphasize structural, chemical, and temporal controls and encourage the three-dimensional thinking used by productive explorationists as they face unsolved problems. This upper-level undergraduate text is fully illustrated and meticulously indexed. Its reliable, authoritative coverage assumes an upper-level command of chemistry and physics, as well as mineralogy, petrology, and structural geology. Outstanding features . . . develops and combines the abilities of the explorationist and of the researcher of ore-forming processes structures the geologic descriptions into groupings recognized by researchers and explorers alike builds confidence, revitalizes curiosity, and encourages expanded thinking emphasizes that the days of easy discovery of outcropping ores are not over includes revised, expanded, and updated descriptions of districts