lavadominant

Lavadominant, often written lava-dominant, is a term used in volcanology to describe eruptions in which effusive lava output dominates the eruptive energy release over explosive fragmentation. In lavadominant activity, lava flows and lava-dome growth are the primary products and hazards, while explosive events and ash plumes are relatively infrequent or limited in scope.

Characteristics and processes: Prolonged effusive activity lasting weeks to years, channelized lava flows, lava domes and fissure eruptions, and relatively modest or episodic explosive bursts. Magma tends to be basaltic to andesitic with low to moderate volatile content; low fragmentation thresholds allow lava to advance rather than explode. Gas emissions can be significant but do not drive sustained explosions. Surface phenomena include inflation, continued crust formation and cooling, and lava-tube systems.

Common settings and examples: Lavadominant activity occurs at shield volcanoes or fissure systems in hot-spot or divergent-boundary settings. Notable examples include persistent lava flows at Kilauea in Hawaii and lava-flow phases at Fagradalsfjall in Iceland, as well as other basaltic eruptions such as Nyiragongo.

Relation to hazards and monitoring: Because the primary output is lava, hazards center on lava flows threatening infrastructure and communities rather than widespread explosive ash columns; monitoring relies on ground deformation, seismicity related to magma supply, gas flux, and infrared satellite data to track lava advance.

See also: lava dome, effusive eruption, pyroclastic eruption, volcanic hazard.