EELATIONS OF THE WEWE SLATE. 2G9 



slate. The softer layers were at one time certainly in tlie zone of flowage, 

 and under these conditions cleavage developed in the normal jjlanes. Later 

 some of these slates passed into the zone of fracture for them, and a fissility 

 secondary to the cleavage formed along shearing planes. The stronger 

 rocks exhibit beautifully all the phenomena characteristic of deformed rocks 

 in the zone of fracture. 



RELATIONS TO AD.TACENT FORMATIONS. 



In all the exposures north and east of Goose Lake the inferior forma- 

 tion is the Kona dolomite. This dolomite generally pasess upward into 

 the slate by a gradual disappearance of the calcareous matei-ial. The 

 lower and central portions of the formation are pure slates or graywackes. 

 In some cases the basal horizon of the slate, or the upper horizon of the 

 dolomite, is a chert -breccia, undoubtedly of dynamic origin, but resem- 

 bling a conglomerate (PI. VII, fig. 2). Such breccias may be well seen at 

 the contact between the slate and the Kona dolomite in the southeast part 

 of sec. 13, T. 47 N., R. 26 W. (Atlas Sheet XXXIV). The slate at this 

 particular locality becomes coarser-grained in passing toward the base, 

 grading first into a novaculite, then into a, graywacke, and then into a 

 brecciated, cherty quartzite. The chert-breccia at the contact appears to 

 have been produced from secondary belts of chert, which liave appeared 

 within, and perhaps have replaced calcai'eous layers in the (piartzite. When 

 the rock was folded the brittle cherty layers were broken into fragments. 

 This pseudo-conglomerate might possibly be taken by a careless observer 

 as evidence of a physical break between the Kona dolomite and the Wewe 

 slate. 



Southwest of Goose Lake (Atlas Sheet XXXV), below the slate, are 

 islands of Archean rocks. It has been said that here conglomerates have 

 an extensive development adjacent to the Archean cores. In sec. 23 

 T. 47 N., R. 26 ^y., and near the central part of sec. 22, T. 47 N., R. 26 W., 

 contacts are exposed between the Archean and the conglomerates, but 

 no contacts were seen adjacent to the area in the southern part of the 

 SW. J sec. 22, although large exposures of conglomerate were found near 

 those of the granite. 



