Seismicity and velocity structure of Loihi seamount from the 1996 earthquake swarm

Citation
J. Caplan-auerbach et Fk. Duennebier, Seismicity and velocity structure of Loihi seamount from the 1996 earthquake swarm, B SEIS S AM, 91(2), 2001, pp. 178-190
Citations number
35
Categorie Soggetti
Earth Sciences
Journal title
BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA
ISSN journal
00371106 → ACNP
Volume
91
Issue
2
Year of publication
2001
Pages
178 - 190
Database
ISI
SICI code
0037-1106(200104)91:2<178:SAVSOL>2.0.ZU;2-R
Abstract
The largest earthquake swan yet recorded on Loihi submarine volcano took pl ace in July and August of 1996. The swarm consisted of two phases of seismi c activity and was associated with the formation of a pit crater and additi onal faulting of Loihi's summit platform. The first phase of activity was c omprised of predominantly high-frequency events scattered over the southern flanks of the volcano. Following a day of seismic quiescence, the second p hase of activity began, consisting of lower-frequency earthquakes with stro ng T-phases. The phase 2 events took place beneath Loihi's summit, presumab ly marking the formation of the pit crater, Pele's Pit. Data obtained by an ocean-bottom seismometer (OBS) on Loihi during the swarm help constrain a new velocity model for Loihi. The relocated earthquakes, combined with othe r characteristics of the swarm, enabled us to develop a model for the event s leading up to the formation of Pele's Pit that includes (I) a prolonged e ruption, (2) a tectonic event beneath Loihi's south flank, and (3) the drai nage of a shallow magma chamber.