August 23, 1872 Tsunami: Fox Islands, Aleutian Islands, AK, United States

This is the first instrumentally located earthquake and tsunami source. A wide variety of sources were suggested by early investigators for the August 1872 tsunami, but Cox (Reference #65) determined from the difference in the tsunami arrival times at San Francisco and Honolulu that it originated on the Pacific shelf and slope of the eastern Aleutian Islands. The marigraphic evidence of its arrival at St. Paul Island permitted the time and location of its origin to be identified with greater certainty and precision than was possible earlier. Assuming the initial feature of the tsunami propagating southeastward to have been a crest, as considered most likely, its most probable origin time was estimated at about 18:06 UTC on 23 August, and the most probable position of the center of its origin area was estimated at about 52.2N, 168.5W. If the initial feature propagating southeastward was a trough, the origin time was most probably about 18:00 UTC, and the center of the origin area was most probably about 53.3N, 166.4W. The range of possible origin times is considered no greater than about 25 minutes (17:55 to 18:20 UTC). The range of possible longitudes of the center of the origin area is no greater than about 7o (164oW to 171oW); the range of latitudes is no greater than about 3o (51o to 54oN).

(above from Reference #1623)

1872, August 23, (mistakenly 27), 13:00 local time. At Hilo, with still weather, the water in the bay quickly and quietly rose, like the onset of flood tide...It again retreated quickly and quietly; thus, in 1 1/2 hours, 14 oscillations occurred, each subsequent one being weaker than the last. In the end, the water returned to its normal state. No earthquake was felt. It is possible that there was a tsunami with source off Chichizima Island. Sapper's (1927) compendium mechanically connects the mention of the tsunami with the mention of the eruption of the Mauna Loa volcano in the same year. A tsunami of remote origin was observed at Astoria, San Francisco and San Diego. There are not details available. Almost at the same time, a weak tsunami was observed on the Hawaiian Islands (Reference #415).

Reference #542 lists 52N, 172W

Reference #237 lists 52.2N, 166.4W.