Geochemical characteristics of mineral deposits: implications for ore genesis

Abstract

Geochemistry is an important field in the study of mineral deposits because mineralization involves several processes, of which chemical processes are the ones that finally result in the precipitation of metals or formation of minerals. Studying the geochemical characteristics of mineral deposits is, therefore, important in: (a) understanding ore genesis (the usage of term ‘ore’ here does not necessarily mean a mineral deposit that can be exploited at an economic profit); (b) mineral deposit classification; (c) mineral exploration; (d) extractive metallurgy or mineral processing; and (e) geo-environmental studies. Understanding the genesis and classification of mineral deposits have traditionally been carried out together (cf. Westra & Keith 1981; Hitzman et al . 2003; Dill 2010). Knowledge of various geological processes relevant to the mineral deposit formation provides a conceptual framework for the application of geocomputational technique for generating mineral exploration targets (cf. Bonham-Carter 1994; Porwal & Kreuzer 2010; Carranza 2011 a ). Knowledge of ore genesis is important in developing geoenvironmetal models for mineral deposits (Seal & Foley 2002). Cabri (1988) and Clout (2003) have demonstrated the relevance of understanding of the genesis of ore deposits in providing guidance for mineral processing and metal extraction. Thus, of the different fields of application of geochemical characterization of mineral deposits, understanding ore genesis is the most important because it provides information that is essential to the other applications. To understand ore genesis using geochemistry, rock samples from mineral deposits are analysed for any of the following: 1. major/trace elements (Loftus-Hills & Solomon 1967; Ghosh 1972; Pearce & Gale 1977); 2. rare-earth elements (Graf 1977; Fryer & Taylor 1987; Lottermoser 1992); 3. fluid inclusion microthermometry (Sawkins 1966; Eadington 1983; Roedder & Bodnar 1997); 4. solute chemistry (Crerar & Barnes …