This plateau has been little explored and is inadequately mapped. 

 The peninsula is fringed by many small islands. Ungava Bay 

 indents the northeast coast. The bay is about 140 miles wide at 

 its mouth and extends southward a similar distance. Into this bay 

 empties the George River and the Whale River, draining the ex- 

 treme eastern portion of the plateau. Between these rivers the 

 coast is broken by three mud-filled bays. The land rises from the 

 rocky hills of the coast to the irregular uplands. At Fort Chimo 

 the Koksoak River enters the bay and forms banks and shoals to a 

 distance of about 10 miles into the bay. The Koksoak is formed 

 by the joining of the Larch and Kaniapiskau which drain the cen- 

 tral plateau. The Leaf and Payne Rivers drain the area west of 

 the bay. All of these rivers are characterized by extended and 

 regular raised terraces along their courses and by numerous rapids. 



Northern Labrador is mountainous with penetrating fiords, is 

 mostly treeless, and is formed of granite and gneiss. All three 

 coasts are hemmed in by ice the greater part of the year. 



North of the Ungava Peninsula of Labrador and separated from 

 it by Hudson Strait is Baffin Island. This is the largest of the 

 Canadian arctic islands and has an area of 230,000 square miles 

 making it the fourth largest island in the world. The island is 

 long and its much indented coastline is penetrated by three'sizeable 

 bays : by Frobisher Bay and Cumberland Sound on the east coast, 

 and by Admiralty Inlet on the northwest coast. A high, rugged 

 mountain range of crystalline pre-Cambrian rocks rises abruptly 

 along the eastern coast to an average height of 5,000 to 7,000 feet, 

 with some peaks reaching heights of 10,000 feet. Permanent 

 snowfields and icecaps in some places bury or partially cover the 

 sharp peaks and ridges, sending long twisting glaciers down the 

 many valleys to the sea. The east coast is deeply indented by 

 fiords with walls rising precipitously from the water, presenting a 

 formidable barrier. Northwestern Baffin Island, like North 

 Somerset Island to the west, is a rolling limestone plateau surfaced 

 by disintegrated slabs of sedimentary Paleozoic rocks. Along 

 Admiralty Inlet and Prince Regent Inlet the plateau forms vertical 

 walls rising 500 to 1,000 feet. Most of the interior of the southern 

 section of the island is a rolling plateau averaging 2,000 to 3,000 

 feet. The southern coastal upland dips to the north and west 

 toward the broad, lake-dotted and swampy plain west of the two 

 large lakes, Amadjuak and Netsalik. 



Devon and Ellesmere Islands are the largest of the northern 

 group of Canadian islands lying to the north of Baffin Island. The 



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