Open AccessThe energetic 2010 M W 7.1 Solomon Islands tsunami earthquake
Author(s) -
Newman Andrew V.,
Feng Lujia,
Fritz Hermann M.,
Lifton Zachery M.,
Kalligeris Nikos,
Wei Yong
Publication year - 2011
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.2011.05057.x
Subject(s) - geology , seismology , trench , tsunami earthquake , subduction , subsidence , moment magnitude scale , aftershock , submarine pipeline , seismic moment , tectonics , geomorphology , oceanography , fault (geology) , chemistry , geometry , mathematics , organic chemistry , layer (electronics) , structural basin , scaling
SUMMARY On 2010 January 3 a moment magnitude M W 7.1 earthquake struck the Solomon Islands very near the San Cristobal trench, causing extensive landslides and surprisingly large tsunami waves. Because of the unique proximity of islands to the trench (<20 km) and earthquake, a post‐seismic survey successfully identified unexpected widespread coseismic subsidence towards the trench (up to 80 cm), with no discernable post‐seismic deformation. Approximately 1000 km from the earthquake ocean‐bottom pressure sensors measured 1–2 cm open‐ocean tsunami waves. Though spatially limited, the local tsunami wave heights up to 7 m were comparable to the much larger adjacent 2007 M W 8.1 earthquake. The seismically determined focal mechanism, broad‐scale subsidence, tsunami amplitude and open ocean wave heights are all explained by an extremely shallow low‐angle thrust adjacent to the impinging subduction of the two seamounts near the trench. This event belongs to a potentially new class of shallow ‘tsunami earthquakes’ that is not identified as deficient in radiated seismic energy.