July 12, 1911 Tsunami: Philippine Trench, Philippines

Reference #414:

1911, July 12, 04:07.6 UTC, 9 N, 126 E, depth 50 km, magnitude 7.75. There was an earthquake with pleistoseismic zone in the valley of the Agusan River. At Talacogon, the tremors lasted 3 minutes and were preceded by weaker oscillations. According to accounts, high waves formed in one of the lakes, flooded the shore and travelled far inland [seiches?]. At Butuan, the earthquake lasted 2 minutes, and began with very weak movements. Almost all the homes, both pile as well as brick, were damaged. Trees were ripped from the ground. Cracks appeared in the ground. People bathing in the river, related that the water first rushed from the western shore to the eastern, and then back again. The movement of the water was so strong, that an enormous beam, secured with a thick reed, was ripped off and carried away [seiches on the river]. Listed as questionable tsunami.

Reference #1187:

1911, July 12, 12:09 p.m. Agusan Valley: Talacogon - there took place a very violent earthquake which wrought great havoc in the convent and church... In one of the lakes the high waves produced by the earthquake invaded the shore and penetrated far into the land. Most likely an earthquake included seiche. La Paz - suddenly there arose some waves of such dimensions and confused directions that the oarsmen needed all their skill and strength to prevent the capsizing of the boat... Veruela... The ground showed waves like those of water, and the commotion of the waters of the river was imposing. The ground was fissured everywhere and in many places of the river formed quite extensive banks of mud and sand, leaving not enough depth for small boats. During three days, the river water was so muddy that it could not be used for any household purposes.

Reference #10958:

1911, July 12. In Lake Mainit, high waves invaded the shore and entered the land (SEASEE, 1985). In the town of La Paz in present-day Agusan del Sur province which is near the Agusan River, strong waves suddenly appeared that almost drowned strong skillful oarsmen. Listed as a seiche.