CHAPTER XV. 



THE GEOLOGY OF WATONWAN AND MARTIN COUNTIES. 



BY WARREN UPHAM. 



Situation and area. Watonwan and Martin counties lie in southern 

 Minnesota, the former being directly north of the latter, which borders on 

 Iowa. They are a little west of the central meridian of the state. The 

 distance of Madelia in Watonwan county southwest from Minneapolis and 

 St. Paul is 87 miles; and Fairmont in Martin county is 27| miles south, 

 and two miles west of Madelia. From the east line of Martin county to 

 the Mississippi at La Crosse is 150 miles; and from the west line of these 

 counties to the line between Minnesota and Dakota is 80 miles. 



Both these counties are rectangles, the extent of Watonwan being 

 twenty -four miles from east to west and eighteen from north to south; 

 while Martin county reaches six miles farther east, and is thirty miles long 

 from east to west, with a width of twenty-four miles. The area of Waton- 

 wan county is 435.45 square miles, or 278,689.92 acres, of which 1,638 acres 

 are covered by water. The area of Martin county is 723.89 square miles, 

 or 463,288.40 acres, of which 12,267.35 acres are covered by water. 



SURFACE FEATURES. 



Natural drainage. Watonwan county is wholly drained by the river of 

 the same name, which empties into the Blue Earth river about three miles 

 below Garden City in Blue Earth county. The North and South forks of 

 the Watonwan river, having their sources in Cottonwood county, traverse 

 respectively the northern and southwestern parts of Watonwan county, 

 each receiving several tributary creeks, and are united in one stream two 

 miles west of Madelia, and about twenty miles, following the course of the 



