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Abstract On 3 May 2018, Kīlauea Volcano, one of the most active volcanoes in the world, entered a new eruptive phase because of a dike intrusion in the East Rift zone. One day later, an Mw 6.9 earthquake, which was likely trigged by the dike intrusion, occurred in the submarine south flank of Kīlauea Volcano. In mid-July, an ocean-bottom seismometer (OBS) array consisting of 12 stations was deployed on the submarine south flank of Kīlauea Volcano to monitor the aftershocks and lava–water interaction near the ocean entry. Eleven OBSs were recovered in mid-September. Preliminary evaluation of the data reveals a large number of seismic and acoustic events, which provide a valuable dataset for understanding flank deformation and stability as well as lava–water interaction. Here, we introduce this dataset and document notable instrument malfunctions along with some initial seismic and acoustic observations.
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Complex staged emplacement of a basaltic lava: The example of the July 1974 flow of Kīlauea
Abstract Basaltic lava flows can be highly destructive. Forecasting the future path and/or behavior of an active lava flow is challenging because topography is often poorly constrained and lava has a complex rheology and emplacement history. Preserved lavas are an important source of information which, combined with observations of active flows, underpins conceptual models of lava flow emplacement. However, the value of preserved lavas is limited because pre-eruptive topography and, thus, syn-eruptive lava flow geometry are usually not known. Here, we use tree-mold data to constrain pre-eruptive topography and syn-eruptive lava flow geometry of the July 1974 flow of Kīlauea (USA). Tree molds, which are formed after advancing lava encloses standing trees, preserve the lava inundation height and the final preserved thickness of lava. We used data from 282 tree molds to reconstruct the temporal and spatial evolution of the ~ 2.1 km-long July 1974 flow. The tree mold dataset yields a detailed dynamic picture of staged emplacement, separated by intervals of ponding. In some ponded areas, flow depth during emplacement (~ 5 m) was twice the preserved thickness of the final lava (2–3 m). Drainage of the ponds led to episodic surges in flow advancement, decoupled from fluctuations in vent discharge rate. We infer that the final breakout occurred after the cessation of fountaining. Such complex emplacement histories may be common for pāhoehoe lavas at Kīlauea and elsewhere in situations where the terrain is of variable slope, and/or where lava is temporarily perched and stored.
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- Award ID(s):
- 2119838
- PAR ID:
- 10580480
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Bulletin of Volcanology
- Volume:
- 87
- Issue:
- 4
- ISSN:
- 1432-0819
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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