Amphibolite


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Related to Amphibolite: Amphibolite Facies

amphibolite

[am′fib·ə‚līt]
(petrology)
A crystalloblastic metamorphic rock composed mainly of amphibole and plagioclase; quartz may be present in small quantities.

Amphibolite

 

a schistose metamorphic rock composed chiefly of alumina-bearing amphibole (hornblende) and plagiociase; sometimes contains granite. Amphibolite is formed from various matrices subjected to profound metamorphism sometimes accompanied by metasomatism and the introduction of silica, magnesium, and iron. Some black varieties of amphibolite are used as industrial gems and ashlars.

References in periodicals archive ?
This is based on the following evidences: Field relations between the different lithotypes of metabasites reflect the occurrence of a prograde metamorphism, which is manifested by an increase of metamorphism from the greenschist facies (chlorite and actinolite schists with or without garnet, and metabasalts) to the amphibolite facies (amphibolites with or without garnet).
Both holes collared in amphibolite and intersected 20m wide zones of chlorite-epidote+/-sericite alteration near surface, with anomalous gold values ranging from trace to 0.
The metamorphic rocks of the Silgara Formation in the Santander Massif (Figure 1) were metamorphosed to upper amphibolites facies during the Caledonian orogeny, developing a sequence of metamorphic zones (biotite, garnet, staurolite and sillimanite) that defines the regional thermal structure.
1990) the high-grade metamorphic rocks in both the Chuggin Road and Lime Hill units include biotite, bioitite-cordierite, and sillimanite-bearing paragneiss, migmatitic paragneiss, marble, quartzite, amphibolite, and tonalitic orthogneiss.
The acoustopolarigrams of amphibolite, as a rule, point to the influence of four factors occurring in different combinations and rate: elastic anisotropy, the LAAA effect, microcracks and heterogeneity.
2002): Geochemistry and geotectonic setting of migmatitic gneisses and amphibolites in the Okene-Lokoja area of SW Nigeria.
Other possible minor sources of amphibolite are Early Permian glacial tillites which occur near Lithgow on the western side of the Blue Mountains, in the central Hunter Valley, and in the Shoalhaven region.
Preliminary geological assessment suggests that one important lode is hosted near the margin of an amphibolite rock.
According to Sono Resources Inc, the licenses include both Ghanzi (Kalahari Belt) and Matchless Amphibolite style mineralization.
Metamorphic rocks Amphibolite Dry 32 Gneiss Dry 26-29 Gneiss Wet 23-26 Slate Dry 25-30 Slate Wet 21 Table 2.
These systematics were examined in a sample of banded amphibolite gneiss, part of the Ropes Creek Metabasalt, collected near Carrollton, GA.