472 THE CRYSTAL FALLS lEON-BEAEEfTG DISTRICT. 



considerably, except in the naiTow eastern portion of the tongue, where 

 it is approximately parallel to that of the cong-lomerate, i. e., a few 

 degrees north of east. 



RELATIONS BETWEEN THE CONGLOMERATE ANP THE DOLOMITE SERIES 

 AND CORRELATION WITH THE FELCH MOUNTAIN FRAGMENTALS. 



The relations of the conglomerates to the dolomites are best shown 

 by the distribution of their respective outcrops, as members of the two 

 series are nowhere in contact. In the central portion -of the tongue the 

 conglomerate outcrops are limited to the district between the central granites 

 and the southern area of the Basement Complex. The dolomites, on the 

 other hand, are limited to the country north of the centi-al granite. Its 

 outcrops are found scattered over the northern tier of sections in T. 42 N., 

 Rs. 28 W. and 29 W., and the southern tier of sections in T. 43 N., Rs. 28 W. 

 and 29 W. Between them and the granite to the north is a belt of country 

 devoid of exposures. It is heavily drift covered, consisting of sand j^lains 

 and sand hills, from beneath which no ledges of any kind protrude. This 

 barren belt measures about a half mile in width, in sec. 2, T. 42 N., R. 28 W., 

 gradually increasing in width till it reaches the center of sec. 1 in T. ^3 N., 

 R. 29 W., where it opens out into the large Pleistocene area whose southeast 

 edge is shown on the map (PL LI). In the eastern portion of the district 

 the northern granites and the conglomerates approach each other, and the 

 dolomite belt becomes very narrow, finally disappearing toward the east 

 side of T. 42 N., R. 28 W. 



The relative distribution of the conglomerate and dolomite ledges, 

 when considered with reference to the triangular outline of the area 

 embraced between the northern and the southern granite-schist complexes, 

 suggests that the two formations constitute a western-pitching syncline with 

 the dolomite in the center and the conglomerates with their associated beds 

 on the two flanks. The conglomerates comprising the southern flank are 

 well exposed, but those of the northern flank are not seen. They are 

 believed to underlie the glacial deposits in the barren strip of country 

 bordering the northern granites. The conglomerates, according to this 

 view, are older than the dolomites. 



Toward the center of the dolomite area, in the north half of sec. 6, 

 T. 42 N., R. 28 W., and at a few places farther west, there are feiTuginous 



