CANADIAN ARCTIC 



63"] 



to that found on southern Ellesmere Island. The shaly equivalent of the grapto- 

 litic rocks might occur in the unexplored southern part of Bathurst Island, as 

 some are known on southern Cornwallis and northern Prince of Wales Islands. 

 The western part of the fold belt includes over 1,000 feet of Ordovician and 

 possibly earlier limestone and conglomerate. In part the Ordovician, Cornwallis 

 formation, with over 1,500 feet of shaly limestone and dolomite, is overlain by 

 2,500 feet of graptolite shale of the Cape Phillips formation; in other parts are 

 Ordovician and Silurian black graptolitic shale, argillite, chert with minor 

 dolomite, in all some 3000 feet thick; still elsewhere are over 6,000 feet of 

 Silurian and possibly Ordovician dolomite and limestone. The Devonian in- 

 cludes up to 8,000 feet of marine and non-marine sandstone, siltstone, and shale; 

 2,500 feet of non-marine sandstone, and 4,000 feet of non-marine sandstone, 

 shale, and coal, with marine bands. 



The Parry Islands Fold Belt was folded before the deposition of the Pennsyl- 

 vanian. The synclines generally have broad troughs and the anticlines have 

 narrow crests with the more steeply dipping strata close to the crests. Many 

 folds are doubly plunging but closures are still to be determined. Where the 

 belt abuts the transversal Cornwallis Fold Belt, deformation has resulted in 

 folds of various shapes and orientations, some folds are almost circular in shape, 

 others have curving axes, and some are aligned parallel to those of the Corn- 

 wallis belt (Fortier, 1959). 



Ellesmere-Greenland Fold Belt 



The Ellesmere-Greenland Fold Belt comprises at least 870 feet of Middle 

 Cambrian limestone and minor shale; 4,800 feet of limestone and impure lime- 

 stone with gypsiferous beds, possibly ranging from Cambrian to Middle Ordo- 

 vician; up to 4,400 feet of the Middle Ordovician Corwallis formation; 3,700 

 feet of the Ordovician to Middle Silurian Allen Bay formation; at the very 

 least 1,500 feet of Middle to Upper Silurian limestone, silty limestone, and dolo- 

 mite. The Ordovician to Upper Silurian graptolitic Cape Phillips formation, at 

 least 2,300 feet thick, has been located only north of Baumann Fiord and ap- 

 proximately halfway across the fold belt. Either in the Upper Silurian and/or 

 the Lower Devonian are numerous sections correlated with difficulty either be- 

 cause of the nature of their fauna or their unfossiliferous nature. They differen- 

 tially contain dolomite, sandstone, limestone, siltstone and shale in various 

 degrees of purity, and vary in thickness, the thicker section measuring some 

 4,000 feet. Marine calcareous shale and siltstone, over 1,000 feet thick, are prob- 

 ably Lower Devonian. The Middle Devonian includes up to 3,800 feet of lime- 

 stone, dolomite, and calcareous shale, in part with coral biostromes and bioherms, 

 overlain by a maximum of 2,900 feet of marine limestone, sandy limestone, 

 sandy shale, and sandstone. The Upper Devonian over 10,000 feet thick, is 

 largely made of non-marine sandstone and shale with thin seams of bituminous 

 coal. 



The above formations were folded, in the southern and western parts of the 

 Ellesmere-Greenland Fold Belt, prior to the Pennsylvanian, but in the eastern 



part of the belt they were folded only in the Tertiary, conformably with non- 

 marine Tertiary and possibly Upper Cretaceous sandstone, shale, and coal. In 

 general the lower Paleozoic miogeosyncline is the most deformed in this belt, 

 folds are symmetrical and asymmetrical, some are overturned, thrust faults and 

 high angle faults are known. The deformation has been more severe northward, 

 where the stratigraphy is less known and some metamorphism produced slates, 

 phyllites, and fine-grained schists (Fortier, 1959). 



Northern Ellesmere Fold Belt 



The Northern Ellesmere Fold Belt underlies the northern coastal area of 

 Ellesmere Island and apparently extends to northwestern Axel Heiberg Island. 

 The rocks comprise sedimentary and volcanic material possibly ranging from the 

 Precambrian to the Tertiary. A part of the belt includes gneisses and intrusions 

 that vary from granitic to ultrabasic. These are undated but it is probable that 

 they are Precambrian in age and were deformed during that time. Some volcanic 

 rocks are pre-Permo-Carboniferous, either Silurian or Devonian, and are ad- 

 joined by greywackes. These rocks and Ordovician beds are mildly metamor- 

 phosed but have complex structures that probably resulted from the Yariscan 

 orogeny. Widespread outliers of mildly folded Permo-Carboniferous strata un- 

 conformably overlie older rocks of more complex structures and indicate that 

 the Late Mesozoic and Tertiary deformation extended to those parts (Fortier, 

 1957). 



After Fortier wrote the above paragraph, a note was published by 

 Blackadar (1960) on a group of gneisses and migmatites between Cape 

 Aldrich and Markham Inlet which he had named the Cape Columbia 

 group. These had been demonstrated on stratigraphic grounds to be 

 older than Middle Ordovician. A potassium-argon analysis was made 

 on a biotite-rich gneiss and an age of 545 m.y. was obtained. This is 

 latest Precambrian or earliest Cambrian. Blackadar concludes that the 

 orogeny formed a landmass from which clastic sediments in the Parry 

 Islands and Ellesmere Island came. By the close of the Paleozoic era the 

 Cape Columbia terrane had been lowered and Permian limestones were 

 deposited on it. 



Cornwallis Fold Belt 



McNair (1960) has reported as follows on the Cornwallis Fold Belt 

 (see Fig. 40.3): 



Two sets of regional structures meet on eastern Bathurst Island. The older, 

 north-south trending Cornwallis folds are characterized by vertical movement 



