Category Archives: Uncategorized

Trachybasalt explanation

First post and a little testing.

I chose the name trachybasalt for this site since I have been working on Jan Mayen volcanic eruptions and quite a few of the Jan Mayen eruptions have produced lavas and tephra of trachybasaltic composition. Here is the definition of trachybasalt from the Concise Oxford Dictionary of Earth Sciences (Allaby, 1990):

The fine-grained, *extrusive equivalent of a *syenogabbro. When *undersaturated, *feldspathoidal minerals take the place of *alkali feldspar to generate feldspathoidal trachybasalts known as *tephrites (*olivine-free) and *basanites (olivine present). Trachybasalts are found on the stable *continental crust and on some oceanic islands.