Mineral Paragenesis

Paragenesis, Mineral

 

the regular, combined occurrence in the earth’s crust of minerals that are related by common conditions of formation. The term “mineral paragenesis” was proposed in 1849 by J. Breithaupt, although the concept had already been introduced as early as 1798 by V. M. Severgin under the name “mineral contiguity.” The concept of mineral paragenesis was most fully developed in the 1920’s by V. I. Vernadskii.

The formation of minerals in paragenetic associations can be of various duration and can occur under different physicochemical and thermodynamic conditions. In many cases, a single paragenetic association of minerals will contain separate mineral inclusions that formed at various times; such mineral inclusions of different ages are called generations.

The most important factors that determine mineral paragenesis are the chemical action and geologic history of the environment and the physicochemical and thermodynamic conditions of mineral formation. Minerals that form under similar conditions constitute paragenetic series; these series are repeated in different deposits in a regular manner. Examples of such series of minerals may be the mineral associations in magmatic rocks, pegmatites, kimberlites, hydrothermal ore veins, and oxidation zones of non-ferrous metal ore deposits.

Mineral paragenesis is closely related to the paragenesis of elements that participate in the formation of minerals. Careful investigation and analysis of mineral paragenesis in rocks makes it possible to reconstruct the course of the mineral-forming process and ascertain the factors that cause regularly repeating combinations of the same minerals in deposits that have similar geochemical histories. The study of mineral paragenesis is very important for finding mineral deposits, because the presence in a rock of a group of easily observed minerals that are characteristic of the given association may point to the presence of industrially valuable satellite minerals.

REFERENCES

Vernadskii, V. I. “Istoriia mineralov zemnoi kory.” Izbr. soch, vol. 4, book 1. Moscow, 1959.
Voronin, Iu. A., and E. A. Eganov. Fatsii i formatsii: Paragenezis. Novosibirsk, 1972.

G. P. BARSANOV