PRE-CAMBRIAN OF NORTHERN ONTARIO AND QUEBEC 321 



the Timiskaming, which forms part of the ancient, tightly folded, 

 peneplaned basement must be pre-Bruce as well as pre-Cobalt. 



W. H. Collins has recently shown that the stratigraphy of the 

 Bruce series in Ontario is closely similar to that of the Lower 

 Huronian of the Marquette region.^ As the gap between the two 

 districts is filled with Palaeozoic sediments this evidence is probably 

 the best we shall ever obtain for the correlation of the Huronian 

 of northern Ontario with that of the south shore of Lake Superior. 

 Accepting it therefore, it follows that the Timiskaming series is 

 pre-Huronian. 



DESCRIPTION OF THE TIMISKAMING SERIES 



In Teck Township the Timiskaming forms a syncline whose 

 width averages pretty closely i| miles, after subtraction of the 

 widths of intrusive masses of porphyry and lamprophyre. The 

 dip of the limbs varies from 60 degrees to 90 degrees. The maxi- 

 mum thickness, calculating the dip of both limbs at 90, is 4,000 

 feet; the minimum, calculating both limbs at 60, is 3,400 feet. 

 Commonly the south limb dips 80 to 90 degrees, the north limb 

 about 60 degrees. Calculated on this basis the thickness amounts 

 to about 3,600 feet, a figure which probably approximates the truth. 

 In the western part of McVittie Township, 15 miles east, where the 

 whole width of the syncline is also exposed, the calculated thickness 

 is closely the same. 



In Teck Township the whole thickness is made up of inter- 

 banded conglomerates and greywackes. At the western end of 

 the syncline near Kenogami station there is a basal band of con- 

 glomerate 400 feet thick, overlain by a massive greywacke con- 

 taining an occasional pebble, the thickness of which is at least 125 

 feet, and may be much greater. About 3 miles to the east of 

 this near Swastika, the basal conglomerate is over 1,000 feet thick. 

 While there was not time available to make detailed sections of 

 the Timiskaming of Teck Township, these observations, coupled 

 with the alternating conglomerate-greywacke composition through- 

 out the entire thickness, indicate pretty clearly that the sediments 

 here are of subaerial origin, such as beach deposits, or continental 



' W. H. Collins, memoir in preparation. 



