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Any of various dark, granite-textured, crystalline rocks rich in plagioclase feldspar and having little quartz.

[French, from Greek diorizein, to distinguish : dia-, apart, between; see dia- + horizein, to divide, limit; see horizon.]

di′o·rit′ic (-rĭt′ĭk) adj.
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References in periodicals archive ?
The inclusions are dioritic type with distinctive boundary with its host rock and chilled border, which indicates the inclusions are not the residual after partial melting, but the product of magma crystallization.
Rocks of the study area are mainly comprised of stage-2 fine to coarse grained granitoids of Ladakh Batholith The dioritic rocks present in the study area are hornblende bearing having high concentration of plagioclase.
Dioritic to granitic plutons intruded both the low- and high-grade metamorphic units in both the Creignish Hills and North Mountain areas (Fig.
26 Ma) crops out on the southern flank of an E-W-trending range of andesite-dacite volcanic hills where a dioritic pluton intrudes the volcanic cover.
2009): Generation of tonalitic and dioritic magmas by coupled partial melting of gabbroic and metasedimentary rocks within the deep crust of the Famantinian Magmatic Arc, Argentina.
On completion of early stage exploration there has been encouraging results of gold geochemical and geological, including anomalous gold (BLEG sampling) from stream sediment sampling draining an area of dioritic intrusives.
This local name was given to unusual textured magmatic rocks of largely dioritic and granodioritic composition occurred in area of the Marktredwitz.
Although the mass is considered an entity, it is composed of different materials, ranging from dioritic to monzonitic quartz.
In many ancient arc systems, uplift and erosion have removed much of the volcanic arc, so that the crystallized products of the magma chambers are exposed as large plutonic bodies, typically of granitic to dioritic composition.
Underlain by a Cretaceous dioritic batholith, the property hosts spectacular intrusive hosted copper-gold mineralization in subhorizontal fractures and veins over an area of at least four square miles.
There, four roughly east-west-trending, nearly vertical calcite-galena veins cut Grenville-age granitic and dioritic gneiss; these are the Nash (Coal Hill), Jepson (Pardee, Victoria), Ross and Robinson (Indian River) veins.