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Related to trachytic: Perthite, Trachytic Texture


 (trā′kīt′, trăk′īt′)
A light-colored igneous rock consisting essentially of alkali feldspar.

[French, from Greek trākhus, rough.]

tra·chyt′ic (trə-kĭt′ĭk) adj.


(Geological Science) (of the texture of certain igneous rocks) characterized by a parallel arrangement of crystals, which mark the flow of the lava when still molten
References in periodicals archive ?
enc] RaFm Basaltic andesite Doleritic AN52A RaFm Dacitic vitric-tuff (-15% C) AN52B RaFm Dacitic vitric-tuff (-15% C) AN20 RaFm Andesite Doleritic AN21A RaFm Andesite Doleritic AN21B RaFm Bt-Granite Hypidiomorphic AN22 RaFm Monzogranite Allotriomorphic AN23 RaFm Granodiorite Hypidiomorphic AN24 RaFm Basaltic andesite Trachytic AN25 RaFm Andesitic crystal-rich tuff AN26 RaFm Dacitic crystal-rich tuff AN27 RaFm Andesitic/Dacitic crystal-rich tuff AN20A PlaFm Gabbro/basalt Doleritic AN20B PlaFm Gabbro/basalt Ophitic AN20C PlaFm Gabbro/basalt Ophitic AN20D PlaFm Gabbro/basalt Doleritic AN20E PlaFm Gabbro/basalt Subophitic Sample Main mineralogy ANC1 Pl+Qz+Afs+(Bt) ANC10 Afs+Qz+(Bt) ANC3 Qz+Pl+Ms/Chl+(Opq) ANC4 Pl+Cpx+Ilm ANC5 Cpx+Pl+Ilm+(Ol?
Hornblende-feldspar porphyries, displaying flow or trachytic textures, occur as the extrusive equivalent of the intrusive dikes.
Many samples preserve relict igneous or sedimentary textures, such as intergranular and trachytic textures in mafic flows, eutaxitic banding in felsic flows, ffagmental texture in tuffaceous rocks, and bedding in epiclastic rocks.
loose, fragmental) know as local trachytic basalt-andesite with an estimated age of 20000-30000 years BP (Asio 1996; Jahn and Asio 1998).
Where the road crosses the Reventazon at Angostura, the river cuts its way through a mass of a solid trachytic porphyry.
All Samoan tempers were derived alike from basaltic or associated trachytic source rocks, but the beach sands, colluvial debris, and crushed rock that served as temper in other Samoan sherd suites are unlike the stream sands used for Pulemelei temper.
5 mm in maximum dimension, in a groundmass with a trachytic texture.
There are two types of deposits on Sardinia, a sedimentary bentonite of Miocene age and a hydrothermally altered trachytic tuff (Annedda, 1956).
The youngest rocks outcrop only in the southern sector of the island (Monte Guardia) as a sequence of partly subaerial pyroclastic and trachytic lava deposits.
The well-preserved igneous texture of fresh trachyandesite is trachytic as shown by fluidally aligned plagioclase laths up to 0.