M 7.8 Earthquake - July 1990, Philippines

At 16:26 local time on 16 July 1990, a surface magnitude 7.8 earthquake struck Luzon, forming a 125 km-long ground rupture that stretched from Dingalan, Aurora to Kayapa, Nueva Vizcaya, due to lateral movements along the Philippine Fault Zone and the Digdig Fault. The quakes epicentre was close to the town of Rizal, north-east of Cabanatuan City, and caused damage across an area of around 20,000 km2, stretching from north-west Manila, through central Luzon and into the Cordillera Mountains¹.

The tourist destination of Baguio City was one of the worst-hit locations, with close to a thousand deaths occurring here due to building collapse, including high-rise hotels¹. For the first 48 hours after the quake, the city was isolated from the rest of the country due to landslides blocking transport routes².

Only one building in Cabanatuan City was destroyed killing 154 people and in Dagupan City, liquefaction caused buildings to sink by as much as 1 m leading to flooding across some of the regions of the city that decreased in elevation². The towns of Rizal, Laur, Bongabon, Gabaldon, Digdig, Puncan and Imugan were also badly affected¹. In the province of La Union, east Luzon island, 2387 families were displaced when two coastal villages sank².

¹ PHIVOLCS. 2001. The July 16 Luzon earthquake.
http://www.phivolcs.dost.gov.ph/Earthquake/1990LuzonEQ_Monograph/forewor...

² Wikipedia. 2007. 1990 Luzon earthquake
http://en.wikipedia.org/wiki/1990_Luzon_earthquake