Trachytic Texture

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Trachytic Texture

 

a texture of extrusive rocks in which the groundmass contains little volcanic glass and consists predominantly of minute tabular crystals, namely, sanidine microlites. The microlites are parallel, forming flow lines along the directions of lava flow and around inclusions. Trachytic texture occurs in rocks that are rich in alkalies; hence the vitreous mass of the rocks has a relatively low viscosity. Trachytic texture is especially characteristic of trachytes and rocks similar to trachytes. (See alsoTEXTURE AND STRUCTURE OF ROCKS. ) [26–513—4]

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.