porphyritic rock


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Related to porphyritic rock: Porphyritic Texture, Pyroclastic rock
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.porphyritic rock - any igneous rock with crystals embedded in a finer groundmass of mineralsporphyritic rock - any igneous rock with crystals embedded in a finer groundmass of minerals
groundmass - (geology) the matrix of fine-grained crystalline material in which larger crystals are embedded
igneous rock - rock formed by the solidification of molten magma
References in classic literature ?
The soil, in fact, was bestrewn with quartz and porphyritic rocks.
The property has intense hydrothermal alteration developed in volcanic rock intruded by quartz-feldspar porphyritic rock displaying textures consistent with epithermal systems.
The porphyritic rock types used also have a petrographically wide range.
Thus, the porphyritic rock types are the result of mineral accumulation, and the aphyric rock types are the result of mineral separation.
As the landscape changes, taking in Lindisfarne and Budle Bay, and - less visibly - sandstone and igneous and porphyritic rock, the soundscape will describe a similar trajectory.
These crystals allow easy identification of porphyritic rock.
One of these boulders, (A quartz-feldspar porphyritic rock with disseminated MoS2,) which are typically angular, and up to 50 kilograms in weight, was recently assayed and returned an analysis of 7.