September 21, 1897 Earthquake: Mindanao, Zamboanga, Sulu, Isabela, Philippines

Reference #414:

1897, Sept. 21, 13:15 [local time, Sept 21, 1897, 05:12 UTC]. There was a destructive earthquake (6 N, 122 E on the southwest of the Philippine Islands, with a maximum intensity of VIII (IX Rossi-Forel), magnitude 8.7. It affected Mindanao Island, the Sulu archipelago and the islands to the south of the Visayan Sea. The dimensions of the area of perceptibility were 800 x 800 km. The earthquake was accompanied by an enormous number of aftershocks which were registered for 18 months.

At Zamboanga, the church, the priest's house and the majority of other stone structures collapsed. There was similar destruction at Ayala, Tetuna, Mercedes, and Bolong. The banks of the Tetuan River collapsed. A large crevice traveling from the sea inland, and many other fissures appeared in the surface of the ground at Magay. Near Bolong, a crack 50 m long and 1 m wide formed in the ground and ejected water and sand. At Isabela, all structures suffered heavy damage. At Maybung, the soil cracked. Buildings suffered damage at Porto Santa Maria.

The steamship "Brutus", situated near Zamboanga, felt a strong seaquake. Waves arose, moving to the east and breaking on shore near Zsmboanga about 10 minutes later.

At Dapitan, the earthquake lasted almost a minute, but did not cause damage. Moderate oscillations were registered in the provice of Iloilo and Capis (at Passi, San Joaquin and other places), on Negros and Cebu Islands, in the valley of the Agusan River, and at Vernela. A weak earthquake was registered at Puerto Princesa on Palawan Island, Kudat and other places on the northern coast of calimantan Island. The oscillations were not felt on Labuan Island (Sabah, Malaysia).

Some sources indicate that there was an eruption of the volcano on Jolo Island.

At Zamboanga, about 15:00 (local time), an earthquake recurred with the same force as the preceding one. Then a phenomenon occurred which caused great panic. The sea level fell 5 m, and then rose and fell with great speed. After several such oscillations in level, sea waves began to flood the city, although they did not advance further than the first few homes.

Reference #1072:

1897, Sept 21. Intensity IX.

Reference #88:

1897, Sept 21, 05:12 UTC, 6 N, 122 E, shallow depth, magnitude 8.7.

Reference #1006:

1897, Sept 21, 05:12 UTC, 6 N, 122 E, shallow depth, magnitude 8.7.