Jantjaet 8, 1915] 



SCIENCE 



49 



profound geologic and geographic interest 

 and each so distinctive as to be especially 

 attractive. 



The relief of a country may be expressed 

 in terms of water power, and considering 

 the rainfall the water power is propor- 

 tional to the relief. From this point of 

 view the Pacific coast relief is greatly in 

 excess of an equal area of the Atlantic 

 coast. 



The area of the direct drainage into the 

 ocean from the Atlantic States is approxi- 

 mately 284,000 square miles,^ while that 

 into the Pacific, not counting the Colorado 

 River, is about one fourth greater than 

 that of our Atlantic coast, and yet the 

 energy represented by the Pacific drain- 

 age is more than seven times that of the 

 Atlantic coast. By far the greater portion 

 is undeveloped and gives some idea of the 

 latent possibilities of the empire of our 

 west. Attention should be called to the 

 fact, however, that much of the Pacific 

 coast power is in the Columbia river, of 

 which the greater part lies east of the 

 mountain belt, but, even excluding that 

 portion of the Columbia, the enormous 

 power of the mountain belt greatly exceeds 

 that of an equal area along our Atlantic 

 coast. 



With this may be coupled also that of 

 the production of precious metals, which 

 are vein deposits formed as an adjunct of 

 stresses that express themselves in relief. 

 The production of precious metals in the 

 mountain belt of the Pacific coast in recent 

 years has been hundreds of times that of 

 the Atlantic States. 



The mountaia-building period on the 

 Pacific coast bordering the larger ocean 

 may have been longer and more intense 

 than that on the Atlantic, resulting in 

 greater and perhaps later segregation, so 

 that erosion has not removed the moun- 



2 Water Eesoiirces Paper No. 234, pp. 52-57. 



tains, as has been the case upon the At- 

 lantic side. 



That this is not simply a matter of time, 

 but of actual deformation and uplift, may 

 be inferred from the enormous deposits of 

 limestone and coal to the east, which indi- 

 cate not only a region of low relief but low 

 relief of wide extent. Strengthening the 

 contrast in the relief of the coasts but bal- 

 ances the values of the mineral deposits. 



PACIFIC COAST MOUNTAIN BELT 



The continental feature bordering the 

 Pacific coast of the United States is a 

 mountainous belt of surpassing grandeur. 

 Lying between the Great Basin platform 

 of the interior on the east and the Pacific 

 ocean on the west, it is the crushed and up- 

 heaved edge of the continent along the line 

 of counter stress between the land and sea. 

 The great upfolds of the earth's surface 

 in that region are so young as to preserve 

 much of the prominent form and mass re- 

 sulting from the deformation. 



It is remarkable for its lineal continuity, 

 with a width ranging from 100 to 200 

 miles throughout a length of 2,500 miles. 

 Some of it indeed at both the northern and 

 southern ends is below sea level, but other 

 portions, especially in California, Oregon 

 and Washington, bear the highest peaks in 

 the United States south of Alaska. 



The general form of the belt is slightly 

 sigmoid with a broad coastal curve to the 

 west in northern California and to the east 

 at the international boundary (49th par.), 

 resulting from large structural features 

 which will appear in an analysis of the 

 members of the belt. 



The general features of the belt are two 

 lines or ranges of mountain elevations with 

 a great valley between. For the most part 

 the two lines of mountains appear to be 

 parallel with each other and the coast ; the 

 Sierra Nevada and the Cascade ranges on 



