FROM ST. PAUL TO THE WESTERN PART OF THE STATE. 



531 



as in any formation), the higher beds have nearly or quite lost all traces of their sediment- 

 ary origin, and might readily be classed among "granitic uplifts or intrusions of mcta- 

 morphic rock." 



PO" 



1. Heavy-bedded gray or reddish and whitish-gray 

 coarse quartzite, with vertical joints and obscure 

 lines of bedding. The weathered surface show- 

 ing a conglomeratic character; P>0 ft. 



2. Thinner-bedded and fine-grained quartzites ; 

 15 ft. 



?>. A hiatus, slope covered by soil about 10 ft. 



4. Compact purplish crystalline quartzite, gradu- 

 ating downward into more reddish quartzite; 

 about 85 ft. 



5. Reddish quartzite In thin, sometimes slaty, lay- 

 ers ; 10 ft. 



f>. An irregular seam of red clay, of 2 to 4 inches. 



7. Thinly laminated quartzite in alternating layors 

 of f! inches to 2 foot thick, each one separated by 

 partings of shale or clay; the whole red and 

 mottled, with yellowish- white surfaces, with rip- 

 ple marks ; about 8 foot to bottom of quarry. 



8. Slope covered by talus and rubbish from quar- 

 ry ; about 20 ft. 



9. Thinly laminated quartzite, which in some 

 bands is brittle and friable ; layors all mottled 

 with cream-colored spots or irregular stripes; 

 about 12 ft. 



The lower beds taken together are variegated ; but many of the layers throughout are of 

 a deep brick-red color. In the higher part of the formation some of the beds for a con- 

 siderable thickness are of a grayish-white, or as nearly white as such formations usually 

 are. Still, however, the prevailing color of the mass is reddish-brown. 



Taking into account the rate of dip, which is probably a little less in the higher than 

 in the lower beds, I estimate that the entire thickness of strata, visible above the river 

 level to the point of disappearance beneath the prairie, is not less than fifteen hundred 

 feet, and may be considerably greater than this.* 



Following the course of the river from New Ulm to Fort Tlidgely, there are several ex- 

 posures of reddish-brown "granite" or quartzites, which has been quarried in a few places, 

 but I do not feel entirely sure of its connection with the rocks in the prairie or at the 

 Ferry below. 



Proceeding westward from Fort Ridgely, I had no opportunity of seeing any other 

 formation than the prairie for about thirty miles. At this point near where we crossed 



* Estimating the thickness from the dip observed near the river level, it would be more than 3000 feet. 



