other earthquakes in alaska 397 



Eelation to other Alaskan Earthquakes 



Alaska has been classified as only peneseismic by Comte F. de Mon- 

 tessus de Ballore/^^ who says that "the only important earthquake known 

 is that of September, 1899, at Yakutat Bay." There are other severe 

 earthquakes, however, and the same seismologist, after cataloguing 

 131,292 earthquakes and 10,499 epicenters tip to the end of 1897, assigns 

 12 earthquakes to 7 epicenters in Alaska and 86 earthquakes to 15 epi- 

 centers or localities so considered in the Aleutian Islands^^^ (figure 9). 



^ DE BEHR/riG 



^^a e 



Fir.r'UE 9. — Hahitual Epiceniers in Aleutian Islands awl Bering Sea (after de Mon- 



tessus de BaUore) 



These shocks are presumably chiefly volcanic I'ather thau tectonic 



Dr. G. K. Gilbert credits Alaska with nine shocks of destructive 

 rank^^^ since the beginning of the last century, stating that the record is 

 fragmentary and may omit more than it includes. 



The first recorded earthquake in Alaska is that stated by Grewingk^^* 

 to have occurred in the Sannak and Shumagin islands, south of the 



111 Les Tremblements de Terre, Paris, 1906, p. 414. 



113 Introduction a, un essai de description sismique du globe et mesure de la sismicit6. 

 Beitrage zur Geophysik, band iv, p. 363. 



*i3 Earthquake forecasts, Science, N. S., vol. xxix, 1909, pp. 125-126. 



11* C. Grewingk : Treatise on the volcanic character of certain regions of the Russian 

 possessions. Proceedings of the Mineralogical Society of Saint Petersburg, 1850 ; trans- 

 lated by Ivan Petroff in Report on seal and salmon fisheries and general resources of 

 Alaska, Senate Document 59, 45th Congress, 1st session, p. 313 ; House Document 92, 

 55th Congress, 1st session, part iv, p. 313 ; Tenth Census, 1880, vol. 8, pp. 95-96. 



