Moment Magnitude (Mw):
Greenwich Mean Date:
SANTA CRUZ / VANUATU ISLANDS REGION
Another strong aftershock has occurred in the Santa Cruz Islands aftershock zone. Preliminary analysis determined a surface wave magnitude of Ms 6.1. Analysis quality was fair. We do not have a Moment magnitude for the quake as of yet and the depth was fixed at 33.0 km for quick processing.
Some information has been received regarding the effects of the main Ms 7.9 / Mw 7.5 (NEIC) Mw 7.8 (HRV) earthquake on April 21. Preliminary reports from the Vanuatu Emergency Services said a tidal wave measuring nearly three meters (nine and a half feet) damaged a number of homes in the Solomon Islands. No shaking damage from the earthquake has been reported yet.
The International Tsunami Warning Center (ITWC) in Hawaii confirmed that a significant tsunami was generated by the main shock, however, they do not have measurements within the epicentral region. They reported the following readings: Funafuti Atoll (800 miles east), 10 cm; and Port Villa, Vanuatu Islands (325 miles southeast): 50 cm. No readings were reported from Honiara, Guadalcanal, Solomon Islands (360 miles northwest). The ITWC also reported preliminary information that 18 home in the Torres Islands were damaged or swept out to sea. Height of the tsunami there is estimated at 1-3 meters. A small group of islands locally known as the Banks Islands (location?) reported several boats lost their outboards after being dragged about a bay as several waves (height?) passed through the Islands. Severe shaking was also reported there.