VOLUME XXVIII Number 7 



THE 



JOURNAL OF GEOLOGY 



OCTOBER-NOVEMBER 1920 



THE KATMAI REGION, ALASKA, AND THE GREAT 

 ERUPTION OF 1912 



CLARENCE N. FENNER 

 Geophysical Laboratory, Carnegie Institution of Washington 



In June, 191 2, Mount Katmai was the scene of one of the 

 greatest volcanic eruptions known in history. The material 

 ejected, mostly in the form of pumice and fragmental glass, formed 

 deposits whose total volume has been calculated to amount to 

 nearly five cubic miles/ At the town of Kodiak, a hundred miles 

 away, this fragmental material ("ash") fell to the depth of nearly 

 a foot, and nearer to the volcano hundreds of square miles of 

 territory were completely devastated. 



General knowledge of the effects of this eruption has been 

 derived chiefly from the explorations of several expeditions sent 

 out by the National Geographic Society, the first one under G. C. 

 Martin and later ones under R. F. Griggs.^ The expedition of 

 the summer of 1919 was planned on a considerably more ambitious 

 scale than former ones, and an invitation was extended to the 

 Geophysical Laboratory to co-operate in the scientific work. 



' G. C. Martin, "The Recent Eruption of Katmai Volcano in Alaska," National 

 Geographic Magazine, Vol. XXIV (February, 1913), No. 2, p. 131. 



- G. C. Martin, Nat. Geog. Mag., Vol. XXIV (February, 1913), No. 2, p. 131; 

 R. F. Griggs, Nat. Geog. Mag., Vol. XXXI (January, 191 7), No. i, p. 13; and Vol. 

 XXXIII (February, 1918), No. 2, p. 115; Ohio Journal of Science, Vol. XIX (1918), 

 p. 2. 



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