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Title: Spatiotemporal Variations of Focal Mechanism and In Situ V p / V s Ratio During the 2018 Kīlauea Eruption
Abstract

We examine the spatiotemporal variations in seismic parameters corresponding to the 2018 Kīlauea eruption. We find that the summit area had mainly strike‐slip focal solutions prior to the eruption, whereas normal‐faulting was the predominant feature during the eruption, partially due to the collapse events. In contrast, the majority of the earthquakes in the central south flank had normal‐faulting solutions before December 2017, in agreement with the normal‐faulting of the Hilina Fault System, while there are more reverse solutions during the eruption. We also observe temporal variations in the estimated in situratios corresponding to the eruption, with increases in the summit and decreases in the East Rift Zone. The sustained lowratios below 4 km depth under the summit caldera may suggest persistent ascent of volatiles from the mantle. The lowvalues in the East Rift Zone are probably associated with increased degassing.

 
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Award ID(s):
1928158
NSF-PAR ID:
10447459
Author(s) / Creator(s):
 ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
48
Issue:
18
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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