The science of volcanology advances disproportionately during exceptionally large or well-observed eruptions. The 2018 eruption of Kīlauea Volcano (Hawai‘i) was its most impactful in centuries, involving an outpouring of more than one cubic kilometer of basalt, a magnitude 7 flank earthquake, and the volcano's largest summit collapse since at least the nineteenth century. Eruptive activity was documented in detail, yielding new insights into large caldera-rift eruptions; the geometry of a shallow magma storage-transport system and its interaction with rift zone tectonics; mechanisms of basaltic tephra-producing explosions; caldera collapse mechanics; and the dynamics of fissure eruptions and high-volume lava flows. Insights are broadly applicable to a range of volcanic systems and should reduce risk from future eruptions. Multidisciplinary collaboration will be required to fully leverage the diversity of monitoring data to address many of the most important outstanding questions. ▪ Unprecedented observations of a caldera collapse and coupled rift zone eruption yield new opportunities for advancing volcano science. ▪ Magma flow to a low-elevation rift zone vent triggered quasi-periodic step-like collapse of a summit caldera, which pressurized the magma system and sustained the eruption. ▪ Kīlauea's magmatic-tectonic system is tightly interconnected over tens of kilometers, with complex feedback mechanisms and interrelated hazards over widely varying time scales. ▪ The eruption revealed magma stored in diverse locations, volumes, and compositions, not only beneath the summit but also within the volcano's most active rift zone. Expected final online publication date for the Annual Review of Earth and Planetary Sciences, Volume 52 is May 2024. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Topographic Controls on Pyroclastic Density Current Hazard at Aluto Volcano (Ethiopia) Identified Using a Novel Zero‐Censored Gaussian Process Emulator
Abstract Aluto volcano (Central Ethiopia) displays a complex, hybrid topography, combining elements typical of caldera systems (e.g., a central, flat caldera floor) and stratovolcanoes (e.g., relatively high and steep, radial flanks, related to eruptions occurring clustered in space). The most recent known eruptions at Aluto have commonly generated column‐collapse pyroclastic density currents (PDCs), a hazardous phenomenon that can pose a significant risk to inhabited areas on and around the volcano. In order to analyze and quantify the role that Aluto's complex topography has on PDC hazard, we apply a versatile probabilistic strategy, which merges the TITAN2D model for PDCs with a novel zero‐censored Gaussian Process (zGP) emulator, enabling robust uncertainty quantification at tractable computational costs. Results from our analyses indicate a critical role of the eruptive vent location, but also highlight a complex interplay between the topography and PDC volume and mobility. The relative importance of each factor reciprocally depends on the other factors. Thus, large PDCs (≥0.1–0.5 km3) can diminish the influence of topography over proximal regions of flow propagation, but PDCs respond to large‐ and small‐scale topographic features over medial to distal areas, and the zGP captures processes like PDC channelization and overbanking. The novel zGP can be applied to other PDC models and can enable specific investigations of PDC dynamics, topographic interactions, and PDC hazard at many volcanic systems worldwide. Potentially, it could also be used during volcanic crises, when time constraints usually only permit computation of scenario‐based hazard assessments.
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- Award ID(s):
- 2053872
- PAR ID:
- 10557099
- Publisher / Repository:
- AGU
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Solid Earth
- Volume:
- 129
- Issue:
- 5
- ISSN:
- 2169-9313
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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