PRE-CAMBRIAN LITERATURE OF NORTH AMERICA 745 



18,348 feet in thickness and the Hahfax slates 11,700 feet thick 

 which overHe it. 



Hovey^ states that Archean gneisses appear on Parker Snow 

 Bay, Greenland. They are overlain by Huronian quartzites, 

 quartz schists, etc. 



Malcolm^ reports that the gold fields of Nova Scotia occupy 

 the eastern half of the province bordering the coast. The oldest 

 rocks are either Cambrian or pre-Cambrian sediments consisting 

 of the Goldenville quartzites 16,000 feet thick conformably over- 

 lain by the Halifax slate 14,500 feet thick. Unconformably over- 

 lying them are Devonian or Carboniferous sediments. The 

 quartzites and slates are thrown into folds having an east to west 

 trend. Locally they are altered into gneisses and schists by a 

 granite intrusion. 



Moore^ finds over 9,000 feet of pre-Cambrian sediments on 

 Belcher Islands about seventy miles from the south coast of Hudson 

 Bay. These sediments resemble the Nastapoka and Richmond 

 groups described by Leith and Low. The sediments include iron 

 formation, concretionary limestone, and dolomite, various slates, 

 some of which show marked banding, quartzites, graywackes, 

 and sandstones. The iron formation consists of jaspilite, chert, 

 cherty-iron carbonate, green granules probably iron sihcate, 

 hematite, magnetite, and shale. Diabase sills and basalt flows 

 of uncertain age are associated with the sediments. Moore con- 

 cludes from his study of the concretionary structures of the lime- 

 stones and the granular structures of the iron formations that 

 they were formed in part by algae and other lowly organism. The 

 chief source of the iron solutions, he believes, was lateritic 

 weathering. 



^E. O. Hovey, "Notes on Geology of the Region of Parker Snow Bay," Bull. 

 Geol. Soc. Am., Vol. XXIX (1918), p. 98. 



» Wyatt Malcolm, "Gold Fields of Nova Scotia," Canada Geol. Surv. Mem. No. 20 

 (191 2), 331 pp., 42 pis., 24 figs., 2 maps. 



3 E. S. Moore, "The Iron Formation on Belcher Islands, Hudson Bay with 

 Special Reference to Its Origin and Its Associated Algal Limestones, " Jour. Geol., 

 Vol. XXVI (1918), pp. 412-38, 18 figs. 



