PLATE LIV. 



MlLLE LACS AND KANABEC COUNTIES, 1888. WARREN UPHAM. 



The old route of the Issati from the Mississippi, Rum river, drains Mille Lacs 

 county, and that from the St. Croix, Serpent river, drains Kanabec county. 



The surface of these counties is seldom rough, the most broken part being a low 

 morainic belt that enters from Benton county and extends across both counties in 

 an east-northeast direction, having a width of about four miles. This is frequently 

 composed of coarse gravel and sand with boulders. It is a singular fact that, as rep- 

 resented by Mr. Upham, it is crossed nearly perpendicularly by the principal streams 

 of the county, as well as by many of the subordinate streams, without apparent 

 deflection or derangement of any kind. Most of these counties are underlain by till, 

 with many boulders from the northeastward, the only northwestern drift being in 

 the southern part of Mille Lacs county. 



Granitic rock appears in outcrop at numerous places along the valley of the 

 Rum river, the Ann river and of Snake river, the last being at the upper and lower 

 falls, not far south of the Aitkin county line. On the west branch of Rum river this 

 granite is coarse grained and reddish, without much lithological variation, apparently 

 an extension of that seen in the eastern part of Benton and Morrison counties. In 

 Kanabec county, and especially at the upper and lower falls of Snake river, the 

 granite is gray, rather fine grained, intersheeted with mica schist and much contorted, 

 being apparently a gneiss resulting from metamorphism. It is also associated with 

 considerable amounts of coarse pegmatyte. 



Unconformable over these rocks is a dark-red sandstone, which is in part con- 

 glomeritic, belonging to the Potsdam, which is quite similar to the sandrock and 

 shales seen at Fond du Lac in Carlton county. This is seen in outcrop a few miles 

 southeast of the lower falls of Snake river, and at the south side of T. 41-23 along 

 the banks of the same river, showing a dip E. N. E., which in extreme amounts to 

 20. In the south part of T. 41-23 similar red sandstone is exposed in the banks of 

 the Snake river, affording a thickness of twenty-five feet, alternating with ash-colored 

 clays. About six miles further south and three miles west, sandstone of coarse grain 

 and gray or iron-rusted color appears in the right shore of the same river 300 feet in 

 length, with a width of seventy-five feet. It has a variable eastward dip, the steepest 

 being 15 E. S. E. This rock is somewhat pebbly with quartz pebbles up to three 

 and a half inches in diameter, but has not the character of an ordinary conglomerate. 

 Some layers are of a dull red color. A well at Milaca struck sandstone. 



