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STRUCTURAL GEOLOGY OF NORTH AMERICA 



Fig. 17.19. Tectonic map of southeastern Alaska and adjacent parts of Canada. After Bud- 

 dington and Chapin, 1929. Stippled areas are related bodies of the Coast Range batholith. The 

 solid heavy lines are the axes of anticlinoria and synclinoria that were formed at approximately 



Buddington believes the variations are closely related to interlocking bath- 

 oliths which together build what is known as the Coast Range batholith. 

 The great batholith is paralleled on the west by a belt of injection 

 gneiss, crystalline schist, and phyllite intruded by abundant batholiths, 

 stocks, sheets, and dikes, believed to be outlying masses genetically associ- 

 ated with the main batholith. See cross sections, Fig. 17.20 This zone as 



the same time that the batholith and its satellites were intruded. The dashed heavy lines are the 

 axes of broad Tertiary arches and sags, and also in part of folds associated with the intrusions. 



previously mentioned is the Wrangell-Revillagigedo belt of metamorphic 

 rocks. It is narrow and loses its individuality at the north but widens and 

 is very well defined toward the south. Near the mouth of Gastineau Chan- 

 nel and west of Thomas Bay this belt has a width of about 13 miles; 

 opposite the mouth of Stikine River, about 25 miles; and at the soudi end 

 of Revillagigedo Island, about 35 miles. This composite belt of sedimen- 



