PETEOGRAPIIICAL CIIAIIACTEK OF THE WEWE SLATE. 259 



lower part nf the torination Ix'conies a (|uartzite or ([Uartzite-conj>'loiuerate- 

 These eoug-loinerates, reposing as they do upon the gneissoid granites, are 

 ver\' hirgely composed of detritus derived from tliem (fig. 11). Immedi- 

 ately adjaeeut to tlie Archean cores on tlie Wewe Hills, in tlie centers of 

 sees. 22 and 23, the basal rocks are no more tlian a, mass of granite blocks, 

 cemented by fine debris of the same material. An intermediate rock is a 

 coarsely banded feldspathic quartzite which in the field very closely resem- 

 l)les the original gneissoid granite (PI. X, fig. 1). From these basal 





fcfii-^T^--ryf iTf'T^ii '^ *- ^ -^«t>«t»w>*r^^ 



Slomerate of W, «c. slil. , ir ii,,,r center of 860.22, T. 47 N., U 



memljers there are all gradations to g-ra^'wackes, novaculites, and slates. 

 The slates in places contain pebbles or bowlders of many kinds, and thus 

 become slate-conglomerates. In the higher part of the formation the slates 

 and graywackes pass by interstratifications and gradation into the Ajibik 

 qitartzite. 



The ordinary detritus of the formation differed from very fine mud 

 to coarse, sandy mud, and there were frequent alternations of the various 



