7 research outputs found
Eruption style at Kīlauea Volcano in Hawaiʻi linked to primary melt composition
Explosive eruptions at basaltic volcanoes have been linked to gas segregation from magmas at shallow depths in the crust.
The composition of primary melts formed at greater depths is thought to have little influence on eruptive style. Primary melts
formed at ocean island basaltic volcanoes are probably geochemically diverse because they are often associated with melting
of a heterogeneous plume source in the mantle. This heterogeneous primary melt composition, and particularly the content
of volatile gases, will profoundly influence magma buoyancy, storage and eruption style. Here we analyse the geochemistry
of a suite of melt inclusions from 25 historical eruptions at the ocean island volcano of K¯ılauea, Hawai’i, over the past 600
years.We find that more explosive styles of eruption at K¯ılauea Volcano are associated statistically with more geochemically
enriched primary melts that have higher volatile concentrations. These enriched melts ascend faster and retain their primary
nature, undergoing little interaction with the magma reservoir at the volcano’s summit. We conclude that the eruption style
and magma-supply rate at K¯ılauea are fundamentally linked to the geochemistry of the primary melts formed deep below
the volcano. Magmas might therefore be predisposed towards explosivity right at the point of formation in their mantle
source region