Lava that piles up over a volcanic vent, usually in a rounded mass
A rounded or irregular mound, hill or small mountain composed of lava congealed over a volcanic vent on the flanks or within a crater or caldera. Typically composed of silica-rich volcanic rocks (e.g., rhyolite, dacite) with admixtures of obsidian, agglomerate, volcanic breccia, etc. The lava may be uniform or varied in color and texture; also called a resurgent dome.
Lava Dome has been defined 2 different ways in documents like Glossary, Glossary.