The term catazone (or katazone) designates a region subjected to strong metamorphism, in temperature (more than 700°C) and in pressure, inducing the crystallization of potassium
feldspar, calcium plagioclases, sillimanite,
garnet, etc...
In terms of metamorphic
gradient, it is the facies of granulites and
eclogites, with frequent presence of sillimanite and biotite
gneisses. Catazone is the final stage of metamorphism before fusion or
anatexis.