Magma supply to Kīlauea Volcano, Hawai‘i, from inception to now: Historical perspective, current state of knowledge, and future challenges

Geological Society of America Special Papers
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Abstract

Meticulous field observations are a common underpinning of two landmark studies conducted by Don Swanson dealing with the rate at which magma is supplied to Kīlauea Volcano, Hawai‘i. The first combined effusion rate and ground deformation observations to show that the supply rate to Kīlauea was constant at ~0.11 km3/yr during three sustained eruptions from 1952 to 1971, a quiescent period at neighboring Mauna Loa volcano. This rate was also interpreted as the steady supply rate from the mantle to both volcanoes combined throughout historical time. The second breakthrough involved field evidence that activity at Kīlauea alternates between dominantly effusive and explosive styles over time scales of several centuries, and that the magma supply rate during explosive periods is only 1%-2% of the rate during effusive periods. For the historical period, several later studies concluded that the supply rate to Kīlauea has varied by as much as an order of magnitude, contrary to Swanson’s ­earlier suggestion. All such estimates are fraught with uncertainty, given the poorly known amount of magma stored within the volcano’s rift zones as a function of time—an enduring problem and active research topic. Nonetheless, Swanson’s original work remains an important touchstone that spurred many subsequent investigations and refinements. For example, there is strong evidence that Kīlauea experienced a surge in magma supply during 2003–2007 that exceeded the historical average by as much as a factor of two, and that the surge was followed by a comparable lull before the supply rate returned to “normal” by 2016. There is also evidence for supply-rate variations of similar magnitude during the latter part of the twentieth century and possibly earlier, subject to the aforementioned uncertainty in rift-zone storage. The extent to which variations in the magma supply to Kīlauea can be attributed to partitioning between Kīlauea and Mauna Loa, a long-debated topic, remains uncertain. Since Kilauea’s inception, the net magma supply to the volcano (and also to Lō‘ihi Seamount, since it began growing) has increased, while Mauna Loa’s growth rate has slowed, suggesting that the volcanoes compete for the same magma supply. However, geochemical differences between lavas erupted at Kīlauea and Mauna Loa indicate that they do not share a homogeneous mantle source or common lithospheric magma plumbing system. Both ideas might be correct; i.e., Kīlauea and Mauna Loa magmas may be sourced in differing portions of the same melt accumulation zone and ascend through different crustal pathways, but those pathways interact through stress or pressure changes that modulate the supply to each volcano. Currently, magma supply-rate estimates are facilitated by comprehensive imaging of surface deformation and topographic change coupled with measurements of gas emissions. Physics-based models are being developed within a probabilistic framework to provide rigorous estimates of model parameters, including magma supply rate, and their uncertainties. Further refinement will require intensive multiparameter observations of the entire magmatic system—from source to surface and above, and from the volcanoes’ summits to their submerged lower flanks—in order to account fully for a complex magma budget.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Magma supply to Kīlauea Volcano, Hawai‘i, from inception to now: Historical perspective, current state of knowledge, and future challenges
Series title Geological Society of America Special Papers
DOI 10.1130/2018.2538(12)
Volume 538
Year Published 2018
Language English
Publisher Geological Society of America
Contributing office(s) Volcano Science Center
Description 21 p.
Larger Work Type Book
Larger Work Title Field volcanology: A tribute to the distinguished career of Don Swanson
First page 275
Last page 295
Country United States
State Hawai‘i
Other Geospatial Kīlauea Volcano