The distribution of Pt, Pd, Os, and Ir was examined in the ores of 22 gold ore fields in Siberia and northeastern Kazakhstan and one field in the Urals. The ore-hosting rocks of all of these fields are characterized by low PGE background contents (from 0.3 to 13 ppb with predominant average contents of 5 ppb). Elevated PGE contents (0.1-1.3 ppm) were detected in early albite-potassium feldspar metasomatic rocks, late beresites and listwenites, argillisites (0.08-1.9 ppm), and sulfide-telluride aggregates (2.8-26 ppm) in metasomatic rocks. The max mum average contents of Pt (8.4-18 ppm) were found in the su fide-arsenic ores of the Voronstovskoe, Olimpiadinskoe, Vasil'evskoe, and Ol'khovsko-Chibizhekskoe multistage gold deposits. The main concentrator minerals of PGEs are arsenopyrite, pyrite, and other sulfides. Complex ore occurrences and deposits of this type are characterized by the discontinuous accumulation of Au and PGEs during sedimentogenesis, metamorphism, and late metasomatism. PGEs often show no correlations with Au, probably because their deposition occurred during different stages of a single ore-metasomatic process.
|Состояние||Опубликовано - 1998|
ASJC Scopus subject areas
- Geochemistry and Petrology