Premium
Pressurized magma reservoir within the east rift zone of Kīlauea Volcano, Hawai‘i: Evidence for relaxed stress changes from the 1975 Kalapana earthquake
Author(s) -
Baker Scott,
Amelung Falk
Publication year - 2015
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2015gl063161
Subject(s) - geology , rift zone , magma , volcano , rift , seismology , impact crater , intrusion , magma chamber , petrology , geochemistry , tectonics , astronomy , physics
We use 2000–2012 InSAR data from multiple satellites to investigate magma storage in Kīlauea's east rift zone (ERZ). The study period includes a surge in magma supply rate and intrusion‐eruptions in 2007 and 2011. The Kupaianaha area inflated by ~5 cm prior to the 2007 intrusion and the Nāpau Crater area by ~10 cm following the 2011 intrusion. For the Nāpau Crater area, elastic modeling suggests an inflation source at 5 ± 2 km depth or more below sea level. The reservoir is located in the deeper section of the rift zone for which secular magma intrusion was inferred for the period following the 1975 M w 7.7 décollement earthquake. Reservoir pressurization suggests that in this section of the ERZ, extensional stress changes due to the earthquake have largely been compensated for and that this section is approaching its pre‐1975 state. Reservoir pressurization also puts the molten core model into question for this section of Kīlauea's rift zone.