40. 



The provinces can be better understood if the entire region is assumed 

 to be emergent because they represent the grouping of the islands or 

 parts of the islands into belts or regions of common geology. See Fig. 

 40.2. 



The sedimentary provinces (eugeosyncline, miogeosyncline, and stable 

 interior) have been defined fairly well, and these should be distinguished 

 from and related to the geologic provinces listed above. Also a younger 

 sedimentary basin (epigeosyncline) has been recognized reposing on 

 parts of the older fold belts and geosynclinal divisions. See Fig. 39.13. 



CANADIAN ARCTIC 



GEOGRAPHY AND GEOLOGIC PROVINCES OF THE ARCTIC ARCHIPELAGO 



I 

 i 



The Canadian Arctic Archipelago is a vast domain of islands, channels, 

 bays, gulfs, and peninsulas. It is approximately 1500 miles wide and 

 1500 miles long, and represents the partly and gently submerged northern 

 margin of the North American continent. The major features of its 

 geography and relief may be seen in Fig. 40.1. 



It has been divided into four geologic provinces, namely, (1) the 

 northern part of the Canadian shield, (2) the Arctic Lowlands and 

 Plateaus, (3) the Innuitian region (fold belts), and (4) the Arctic 

 Coastal Plain. 



LOWLANDS AND PLATEAUS 



Definition 



The Lowlands and Plateaus province consists of shelf sediments and 

 intercratonic basins, and is the northern counterpart of the Central Stable 

 Region of the continent. It was called the Arctic Stable Region in the 

 first edition of this book. It will here be considered to include the arches 

 of Precambrian rocks that separate some of the basins. 



Areas of Precambrian Rock 



The exposures of Precambrian rock of the Canadian Arctic have been 

 described by Fortier (1957) as follows: 



Three areas of the Shield, namely, the Baffin-Ellesmere Belt, the Melville- 

 Southampton Belt, and the Boothia Arch, are underlain by Archean rocks and 

 smaller amounts of Proterozoic rocks. The other two areas, the Wellington and 

 Minto Arches, are underlain by Proterozoic formations. 



The Baffin-Ellesmere Belt is the largest and most easterly of the Precambrian 

 areas. It occupies the larger part of Baffin and Bylot Islands, the eastern part 

 of Devon Island, and stretches about half-way along the east coast of Ellesmere 

 Island. The belt is composed chiefly of Archean gneisses and granitic rocks. 

 The structures of the gneisses are complex but a northwesterly trend is preva- 

 lent in southern Baffin Island. Proterozoic strata are found in northern Baffin 

 Island and are gendy flexed along northwesterly to northerly trending axes. 

 Flat-lying or gendy inclined Proterozoic strata also occur at the north end of 

 the belt on Ellesmere Island. 



The Melville-Southampton Belt underlies almost all of Melville Peninsula and 

 eastern Southampton Island, continues across Fury and Hecla Strait, and ob- 

 viously connects with the Baffin-Ellesmere Belt. Little is known about the 



633 



