The 1968 Casiguran earthquake occurred on with a moment magnitude of 7.6 and a maximum Mercalli intensity of IX (''Violent''). The thrust earthquake's epicenter was in Casiguran,

Quezon Quezon, officially the Province of Quezon () and historically known as Tayabas, is a Provinces of the Philippines, province in the Philippines located in the Calabarzon Regions of the Philippines, region on Luzon. Lucena, a highly urbanized ci ...

(now part of

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province). A small non-destructive tsunami was generated and at least 207 people were killed. The majority of the deaths occurred in the collapse of a six-story building in Manila.

Damage

Manila Manila, officially the City of Manila, is the Capital of the Philippines, capital and second-most populous city of the Philippines after Quezon City, with a population of 1,846,513 people in 2020. Located on the eastern shore of Manila Bay on ...

, many structures that suffered severe damage had been built near the mouth of the

Pasig River The Pasig River (; ) is a water body in the Philippines that connects Laguna de Bay to Manila Bay. Stretching for , it bisects the Philippine capital of Manila and Metro Manila, its surrounding urban area into northern and southern halves. Its m ...

on huge

alluvial Alluvium (, ) is loose clay, silt, sand, or gravel that has been deposited by running water in a stream bed, on a floodplain, in an alluvial fan or beach, or in similar settings. Alluvium is also sometimes called alluvial deposit. Alluvium is ...

deposits. A number of buildings were damaged beyond repair while others only suffered cosmetic damage. 268 people were reported to have died during the collapse of the six-story Ruby Tower, located at the corner of Doroteo Jose and Teodora Alonzo Streets in the district of Santa Cruz. The entire building, save for a portion of the first and second floors at its northern end, was destroyed. Allegations of poor design and construction, as well as the use of poor-quality building materials arose. In the district of Santa Ana, one person was injured by debris from a damaged apartment building. Two more people from Aurora sub province and

Pampanga Pampanga, officially the Province of Pampanga (; ; ), is a province in Central Luzon in the Philippines. Lying on the northern shore of Manila Bay, Pampanga is bordered by Tarlac to the north, Nueva Ecija to the northeast, Bulacan to the east, ...

died as a direct result of the quake. Around the town of Casiguran, there were several reports of landslides, the most destructive one at Casiguran Bay.

Aftershocks

The aftershock sequence throughout the month of August included many moderate shocks, including fifteen over 5.0 . The strongest of these occurred on August 3 with a 5.9 event that produced intensities of III–IV in Manila.

Aftermath and legacy

The former location of Ruby Tower in Santa Cruz district is now a memorial hall which stands today.

Notes

References

Sources *

External links

Casiguran Earthquake – 02 August 1968
– Philippine Institute of Volcanology and Seismology
M7.6 – Luzon, Philippines
–

United States Geological Survey The United States Geological Survey (USGS), founded as the Geological Survey, is an agency of the U.S. Department of the Interior whose work spans the disciplines of biology, geography, geology, and hydrology. The agency was founded on Mar ...