80 



EARTH FEATURES AND THEIR MEANING 



ence is, however, difficult to ascertain, for the reason that the 

 former shore features are now covered with water and thus removed 



from observation. In favor- 

 able localities the minimum 

 amount of submergence may 

 sometimes be measured upon 

 forest trees which are now 

 flooded with sea water. In 

 Fig. 74 a portion of the 

 coast is represented where 

 the beach sand is now ex- 

 tended back into the spruce 



FIG. 73. View on Haencke Island, Disen- f oreg f a distance of a hun- 



chantment Bay, Alaska, revealing the shore 

 that rose seventeen feet above the sea during 

 the earthquake of 1899, and was found with sedgy beach grass is growing 



teet Or more, and where 



barnacles still clinging to the rock 

 Tarr and Martin). 



(after 



among trees whose roots are 

 , 



now laved in salt water. 

 At the front of this forest the great storm waves overturn the 

 trees and pile the wreckage in front of those that still remain 

 standing. 



Upon the glaciated rock surfaces of the Alaskan coast, excep- 

 tionally favorable opportunities are found for study of the intricate 



FIG. 74. Partially submerged forest 

 upon the shore of Knight Island, Alaska, 

 due to the sinking of a section of the 

 coast during the earthquake of 1899 

 (after Tarr and Martin). 



FIG. 75. Settlement of a section of the 

 shore at Port Royal, Jamaica, during 

 the earthquake of January 14, 1907, 

 adjacent to a similar but larger settle- 

 ment of the near shore during the 

 earthquake of 1692 (after a photo- 

 graph by Brown). 



pattern of the earth mosaic which is under adjustment at the time 

 of an earthquake. Upon Gannett Nunatak the surface was found 

 divided by parallel faults into distinct slices which individually 

 underwent small changes of level (plate 3B). 



