4(l^c^$^y(Jie^h 



THE 



AMERICAN JOURNAL OF SCIENCE 



[FOURTH SERIES. ] 



Art. XXII. — Geothermal Data from Deep Artesian Wells in 

 the Dakotas ; by N. H. Darton, IT. S. Geological Survey.* 



This paper is intended to set forth new facts as to the 

 underground temperature of a portion of eastern South Dakota 

 and North Dakota, derived from records of temperatures of 

 waters flowing in large volume from nearly level strata lying 

 from 500 to 1500 feet below the surface. These temperatures 

 are found to be exceptionally high over a wide area, but 

 present regular regional variations. The salient features are 

 shown in figure 1, p. 163. 



Nearly all the waters in the great artesian basin of the 

 Dakotas are perceptibly warm, — some are notably so, — but as 

 they are derived from a considerable depth, no attention has 

 been paid heretofore to the geothermal rates which the high 

 temperatures indicate. In the course of several investigations 

 which have been made in the artesian basin, temperatures of 

 many of the flows have been observed, some with great care. 

 The highest temperature recorded is at Harold, in Hughes 

 County, where the flow is stated to be 94*9° F. At Pierre the 

 water has a temperature of 92° F. and supplies a fine swim- 

 ming pool at the sanitarium. At some other localities in the 

 Missouri valley the temperatures of flows are as follows : 



Cheyenne Agency . _ 79° F. 



Crow Creek Agency - 72° F. 



Chamberlain 10° to n*6° F. 



Fort Randall... 80° F. 



Greenwood 70° F. 



Yankton 60° to 64° F. 



* Published by permission of the Director of the U. S. Geological Survey. 

 Read at Montreal meeting of the Geological Society of America, December, 1897. 



Am. Jour. Sci.— Fourth Series, Vol. V, No. 27.— March, 1898. 

 11 



