SCIENCE. 



[N. S. Vol. XXII. No. 574. 



During our work along the shores of Yaku- 

 tat Bay, and its extension called Disenchant- 

 ment Bay and Kussell Fiord, abundant evi- 

 dence was found to prove that the shores of 

 the great fiord suffered a profound disturb- 

 ance during this earthquake. The evidences 

 of change of level are: (1) physiographic — ■ 

 elevated rock benches, sea caves, chasms, al- 

 luvial fans and beaches, submarine till up- 

 lifted to form shore lines, and the appearance 

 of new reefs and islands; (2) biological — 

 various marine forms, such as Balanus, My- 

 tilus and a calcareous alga clinging to up- 

 lifted rock on which land plants now thrive, 

 but in no case plants more than five years in 

 age; and (3) human — the narrative of the 

 Yakutat natives. Depression is shown by the 

 sea encroaching on and killing trees; and ex- 

 tensive water waves are proved by the destruc- 

 tion of forests along the shores of Yakutat 

 Bay high above the present reach of the waves. 



The fiord, which is about sixty miles in 

 length, has the form of a bent arm, starting 

 from the Pacific as the broad Yakutat Bay. 

 This bay is bordered by a low foreland of 

 glacial debris on the southeast and by Malas- 

 pina glacier, with its fringe of glacial debris, 

 on the west. 



Back of the lowland fringe rises a range of 

 mountains, really foothills of the St. Elias 

 chain, reaching elevations of from 4,000 to 

 6,000 feet. The seaward face of this range 

 rises abruptly out of the low foreland with a 

 steep and remarkably straight front. Into this 

 range Yakutat Bay penetrates, rapidly nar- 

 rowing to the form of a fiord whose lower end 

 is named Disenchantment Bay. At the head 

 of this bay the fiord, thence called Russell 

 Fiord, abruptly turns back toward the ocean 

 and extends out beyond the steep mountain 

 front, ending in a bay-like expansion in the 

 fringing lowland. Three large tidal glaciers 

 — Hubbard, Turner and Nunatak — fed among 

 the lofty mountains of the St. Elias chain, 

 enter the fiord. 



The mountainous shores of the fiord have 

 been differentially deformed, some parts show- 

 ing no change in level, while one shore, that 

 south of Turner glacier, has suffered eleva- 

 tion of from 33 to 47 feet. Accompanying 



this change there has evidently been faulting 

 along some of the arms of the fiord. That 

 this faulting has been complex is indicated by 

 the presence, in a number of places on the 

 land, of numerous new faults close together 

 and parallel to each other and, in general, to 

 the strike of the St. Elias chain. The best of 

 these were observed on the nunatak at Nuna- 

 tak glacier, where the maximum throw of 

 single faults reached three feet, though the 

 aggregate throw of all the faults in a given 

 region amounted to several times this figure. 

 The region has apparently been warped and 

 broken into a series of blocks which are tilted 

 in a complex relation, and which themselves 

 have suffered extensive minor faulting. In 

 one place, along the lower part of Russell 

 Fiord, the faulting apparently follows a line 

 of earlier movement. 



The uplift is confined to that part of the 

 region which lies along and inside of the steep, 

 straight mountain front, while on the low 

 fringe of foreland, and in the Malaspina gla- 

 cier region, there is, for the most part, no 

 evidence of any change of level excepting at 

 the very mountain base. Locally, however, 

 and especially near the mountain, there is 

 depression along the shores of the lowland, 

 reaching a maximum of from three to five 

 feet. Professor Riissell long ago assigned to 

 this mountain front a faiilt origin on the basis 

 of the form, and our observations confirm this 

 interpretation. Moreover, there is clear evi- 

 dence of a still earlier, though very recent, 

 movement along this major fault line. 



Our observations, which later will be pub- 

 lished in full, indicate that the earthquake 

 was the result of a great upward movement 

 along the front of the St. Elias chain, with 

 minor differential movements of large and 

 small kind, together complexly fracturing the 

 crust along and near the shores of the fiord. 

 Along the extreme front of the mountains the 

 uplift was from six to nine feet; but further 

 back it locally reached a much greater figure, 

 in one place, as previously stated, causing an 

 uplift of the coast of 47 feet. 



Ralph S. Tare, 

 Lawrence Martin. 



Cornell University. 



