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

References in periodicals archive ?
The Raman spectrums obtained were evaluated with Crystal Sleuth program to determine the mineral paragenesis. Chemical composition of pyrolusite was determined with microprobe analysis conducted at Montan Universitat in Leoben (Austria).
Mineral paragenesis in the study area was investigated with ore microscopy studies as well as XRD, Raman spectroscopy, and microprobe analysis for pyrolusite.
Neuhoff, P.S., Fridriksson, T., and Arnorsson, S., Porosity evolution and mineral paragenesis during low-grade metamorphism of basaltic lavas at Teigarhorn, Eastern Iceland, Am.
If the protolith is siliceous carbonate, then calc-silicate minerals will be part of the mineral paragenesis. Figure 2 illustrates the stability field of periclase, brucite and some of the other mineral assemblages that are expected at 1.5 kbar in silicious dolomite, a geological setting that can be approximated by a CaO-MgO-Si[O.sub.2]-[H.sub.2]O-C[O.sub.2] system.
The heavy mineral paragenesis is characterized by ilmenite, zircon, rutile and garnet, sometimes with substantial amounts of other heavy minerals.
Inevitably this would be followed by a "systematic" arrangement of the minerals (native elements, sulfides, sulfosalts, oxides, etc.), with perhaps some token exhibits devoted to mineral paragenesis; that is, how some of the more common minerals formed.
The mineral associations that typically occur in Sweet Home mine specimens are discussed, but mineral paragenesis is not.
Mineral paragenesis (order of mineral growth) provides a record of relative progression of time, and as demonstrated in Figure 190, the specimens of the Sweet Home mine distinctly display an order of mineral growth.
Detailed studies of mineral paragenesis have been carried out in the Cave in Rock bedding replacement deposits by various writers including Hall and Friedman (1963), Heyl (1982), and Richardson and Pinckney (1984).
Hall and Friedman (1963) and Richardson and Pinckney (1984) give contradictory information about the later mineral paragenesis. The earlier writers found overwhelming evidence that the deposition of quartz, sphalerite, galena and late fluorite occurred under conditions oscillating near equilibrium (between precipitation and solution) over a long period of time.
Mineral paragenesis has been described in two articles, one of which was published by Zebec and Soutek in 1986 and another by Zorz et al., in 1988.
His more important contribution was his work on mineral paragenesis: Die Paragenesis der Mineralien (1849).]