The Jan 11, 1909 earthquake is a well documented, large and significant event. The time of the event differs in various accounts from 3:30 to 4:30 PM. Numerous newspaper sources were found, and the event was widely felt from Port Angeles, Victoria, Vancouver and Chilliwack in the north to Tacoma and Aberdeen in the south. There were no reports of felt shaking from Olympia or Portland, and presumably the earthquake was not felt there.
Some damage occurred. The San Juan Islander, reporting from Friday Harbor, says: "Here buildings rocked enough to crack some chimneys, stop clocks, and cause some breakage of window glass, crockery, etc. In the valley, the large chimneys on P.E. Peterson's house were shaken down as were also one of the chimneys of Chas. Peterson's house at Argyle and one on Mrs. Schmidt's house of Kanaka Bay. Most of the monuments in the cemetery were moved. Here in town Dr. Wright is the only one who suffered damage worth mentioning. In his drug store a large number of bottles and medicines were thrown from the shelves and broken, and one chimney on the drug store building and one on his residence were cracked and moved horizontally so as to necessitate rebuilding them from the roofs up. Navigators and others out on the water, whether in large or small craft report that when the first shock occurred their first thought was that their boats had struck submerged logs or unknown reefs. The captain of the Rosalie ordered the engines reversed thinking that the vessel had struck a big log or rock."
Although it has previously been suggested (Garry Rogers, 1983) that this earthquake occurred at depth, based on a lack of reported aftershocks, It appears that at least seven aftershocks were felt in the San Juan Islands. Garry Rogers (1983) calculates the magnitude of this event to be around magnitude 6.0 and states: " Felt reports from newspapers limit this epicentre to the San Juan Islands region where several instances of damage occurred Felt information also clearly shows that the size of the isoseismal map is between that for the 1965 Seattle earthquake and the 1976 Gulf Islands earthquake (Figure 7). The magnitude is about 6 according to Toppozada's (1975) felt area relationship."
All reported aftershocks in the San Juan Islands, particularly noted at Lopez. Blasting at several locales was also mentioned. (Waldron Island: San Juan Islander, Feb. 5, 1909, Fri., p. 8, c. 5; Bellingham: Friday Harbor Journal Feb. 11, 1909, Thurs., p. 8, c. 4, 5), though it seems unlikely to have been the cause of all the reports. |