46 



RECONNAISSANCE IX NORTHERN ALASKA IN 1901. 



present the concavity of their curve to the north, and, as suggested, appear to owe 

 their origin to a part of the same uplift that formed the more abrupi 

 front of the main range. They seem to be persistent features between 

 the Colville and the head of Chipp (Ikpikpuk) River, where they trend 

 a little north of west. Farther west they presumably merge into the 

 Meade River Mountains, at the head of Meade River, in latitude (lit 20', 

 and probably continue still farther westward to the Arctic Ocean, where 

 much the same type of topography, also cut in Mesozoic rocks, appears 

 in the region north of Cape Beaufort. 



Where traversed by the Survey party, the most pronounced of 

 these ridges occurs about 20 miles north of the mountains. It is low. 

 broad, and somewhat rounded. Its highest points rise only 500 to 600 

 feet above the general plateau level, or about 1,200 feet above the bed 

 of Anaktuvuk River. A sectional profile of this ridge, sketched from 

 a point a few miles above it, on the Anaktuvuk, is presented in fig. 3. 



ARCTIC COASTAL PLAIN. 



In latitude approximately 69° 25', at a distance of 80 miles from the 

 mountains, and at an elevation of about 800 feet, the northern edge 

 of the above-described Anaktuvuk Plateau gives way to a nearly flat 

 tundra country or coastal plain, which from this point extends about SO 

 miles northward to the Arctic coast, and descends in this distance prac- 

 tically to sea level, with slope so gentle as to be inappreciable to the 

 naked eye. For this feature, by reason of its geographic position, the 

 name Arctic Coastal Plain is here proposed. This plain is practically 

 constructional. The flat surface of its large interstream areas is dotted 

 here and there by extremely shallow ponds and lakelets, which in most 

 instances are without outlet and present no suggestion of the develop- 

 ment of any system of drainage. Along the west side of the Colville the 

 i eroded edge of this part of the plain forms continuous steep bluffs, 

 which gradually decrease in height northward, from 200 feet at the 

 mouth of the Anaktuvuk to about 80 feet at Ocean Point, 40 miles 

 distant, The few rivers that traverse the plain flow with considerable 

 velocity in its inland portion, but toward the coast they become 

 sluggish. 



DRAINAGE. 



COLVILLE RIVER. 



The drainage of this Arctic slope province is essentially north. 



ward, into the Arctic Ocean. The master stream is Colville River. 



The Colville has a drainage basiu of about 30,000 square miles. It rises in the 



