Scientific publications

Talc transformations may be suffered by ultramafic to felsic rocks in a wide temperature and pressure range when chemical components, required for talc formation, are added. The scope of talc formation depends on some geological factors. Significant talc deposits were produced by a certain combination of these factors in peridotitic komatiite fields. However, talc is also formed in pyroxenitic komatiites, picrites and Mg-rich basalts. Talc-forming processes are characteristic of the rock complexes of greenstone structures. They often add to the formation of copper-nickel, diamond, gold and other ore and non-ore deposits, producing the parageneses of consecutive formation. A spatial relationship in some cases is provided by structural-tectonic, petrographic and stratigraphic control. The presence of talc-bearing rocks may provide a generalpurpose direct prospecting sign for high-Mg rock units (serpentinized, talcified ultramafic rocks - serpentinites, soapstone and talc ores) and an indirect prospecting sign for ultramaficsrelated ore deposits and diamondiferous kimberlitic rocks.