TY - JOUR
T1 - Seismic Evidence for a Shallow Detachment Beneath Kīlauea's South Flank During the 2018 Activity
AU - Lin, Guoqing
AU - Okubo, Paul G.
N1 - Funding Information:
We thank technical and monitoring staff at HVO for maintaining the seismic network and making the data available. We are grateful to Donald A. Swanson for his constructive discussions and to Yang Shen and an anonymous reviewer for their helpful reviews. Funding for this research was provided by the National Science Foundation Grant EAR‐1928158.
Publisher Copyright:
©2020. American Geophysical Union. All Rights Reserved.
PY - 2020/8/16
Y1 - 2020/8/16
N2 - We investigate earthquake distribution and focal mechanisms associated with the 2018 Kīlauea volcano eruption in Hawaii. Our high-precision earthquake relocations delineate an aseismic zone bounded by two subhorizontal bands of seismicity at 3.5 and 7 km depths beneath the eastern south flank, both of which are dominated by the shallow-dipping reverse faulting during the 2018 activity. We interpret the deeper seismicity as related to the basal décollement that separates the volcanic edifice from the oceanic crust. The shallower seismicity is a feature exhibited in the recent activity and, which we propose, reveals a detachment that either represents the contact between Mauna Loa and Kīlauea volcanoes or coincides with the onland extension of the base of the Hilina slump. We suggest that large earthquakes, such as the 1975 Mw 7.7 and the 2018 Mw 6.9 mainshocks, are capable of triggering failures of both the basal décollement and the shallower surface.
AB - We investigate earthquake distribution and focal mechanisms associated with the 2018 Kīlauea volcano eruption in Hawaii. Our high-precision earthquake relocations delineate an aseismic zone bounded by two subhorizontal bands of seismicity at 3.5 and 7 km depths beneath the eastern south flank, both of which are dominated by the shallow-dipping reverse faulting during the 2018 activity. We interpret the deeper seismicity as related to the basal décollement that separates the volcanic edifice from the oceanic crust. The shallower seismicity is a feature exhibited in the recent activity and, which we propose, reveals a detachment that either represents the contact between Mauna Loa and Kīlauea volcanoes or coincides with the onland extension of the base of the Hilina slump. We suggest that large earthquakes, such as the 1975 Mw 7.7 and the 2018 Mw 6.9 mainshocks, are capable of triggering failures of both the basal décollement and the shallower surface.
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U2 - 10.1029/2020GL088003
DO - 10.1029/2020GL088003
M3 - Article
AN - SCOPUS:85089387577
VL - 47
JO - Geophysical Research Letters
JF - Geophysical Research Letters
SN - 0094-8276
IS - 15
M1 - e2020GL088003
ER -