Bysmalith

bysmalith

[′biz·mə‚lith]
(geology)
A body of igneous rock that is more or less vertical and cylindrical; it crosscuts adjacent sediments.

Bysmalith

 

a magma body having a conic or cylindrical form. Bysmaliths can reach the earth’s surface or end within sedimentary rocks, raising them in the shape of a dome.