Publication Type:

Journal Article

Authors:

Davies, J. F.; Whitehead, R. E.

Source:

Exploration and Mining Geology, Canadian Institute of Mining, Metallurgy and Petroleum, Montreal, QC, Canada, Volume 19, Number 1-2, p.13-22 (2010)

ISBN:

0964-1823

Keywords:

alkalic composition, aluminum oxides, argillization, Asia, Bingham mining district, chemical composition, chemical ratios, chemical reactions, China, copper ores, crystal chemistry, Europe, Far East, feldspar group, framework silicates, france, geochemistry, gold ores, granodiorites, greisen, Hydrothermal alteration, igneous rocks, metal ores, Metallogeny, Metamorphic rocks, metasomatic rocks, metasomatism, mineral composition, mineral deposits, genesis, Mineral exploration, molybdenum ores, oxides, Peru, petrography, plagioclase, plutonic rocks, PORPHYRY COPPER, quartz monzonite, silicates, South America, tin ores, Trace elements, United States, utah, veins, Western Europe

Abstract:

Alkali/alumina and MgO/alumina molar ratio plots graphically portray both chemical and mineralogical changes accompanying potassic, phyllic, argillic, chloritic, and alunitic alteration of quartz monzonites and granodiorites hosting porphyry (as well as lode and greisen) ore deposits. The molar ratio plots can be used to identify different types of alteration. In most cases, the identification based on molar ratios coincides with petrographic data. In those instances where the molar ratio and petrographic identifications do not agree, the mineralogy might need to be re-examined. Hydrothermal alteration studies using trace elements could benefit from the application of complementary alkali/alumina molar ratio plots.

Notes:

GeoRef, Copyright 2018, American Geological Institute.<br/>2010-095261<br/>San Rafael Deposit<br/>Sibert Deposit<br/>Zijinshan Deposit