HAWORTH: THE STRATIGRAPHY OF THE KANSAS COAL MEASURES. 285 



SHALES, PRINCIPALLY SUB-MARINE IN ORIGIN. 



There is no fundamental reason why great shale beds may not have 

 been formed under great fresh water lakes, or fresh water lagoons of 

 varying depths. The shales in the Coal Measures of Kansas, how- 

 ever, probably were principally deposited under salt water. Two 

 general reasons have led to this conclusion. The first is the great 

 frequency throughout almost all the shale beds of traces of calcare- 

 ous matter. Many little limestone layers are found which vary from 

 2 to 10 or 12 inches and which rarely are sufficiently pure to be called 

 limestone. Such formations generally have well preserved marine 

 invertebrate shells within them, showing that they were formed under 

 ocean water. Were all of such formations within the Cherokee shales 

 counted they would probably number 20 or 30. In other shales 

 similar conditions obtain, so that the great mass of the Coal Measure 

 shales either were deposited principally under ocean water or the 

 number of emergences and submergences were manifold greater than 

 the estimates given in the earlier pages of this paper. 



The second reason for believing the Coal Measure shales were 

 deposited beneath ocean water is the great frequency of salt water 

 within them. Not a single instance is known to the writer of water 

 having been obtained at a depth equal to or greater than 200 feet 

 within the shales which was not more or less salty. With the recent 

 extensive prospecting for oil and gas dozens of wells have been 

 drilled, so that the test can be made quite thoroughly over the area 

 prospected. Farther to the west the conditions in this respect seem 

 to be about the same. The deep well at McFarland produced an 

 abundance of salt water, while according to Hay* those at St. Mary's 

 and Wamego seem to have pierced 3 or 4 feet of rock salt. The 

 same author statest that at La Cygne 80 feet of rock salt was passed 

 in a deep well. The writer investigated this matter during the past 

 season and reached the conclusion that there was no satisfactory 

 evidence of rock salt anywhere within the shales passed by the well, 

 but that the production of strong brine here was similar to that in so 

 many other wells. However, the presence of rock salt would only 

 add strength to the argument here deduced. It is difficult to under- 

 stand why the salt water would be so universally obtained over an 

 area so many hundred square miles in extent excepting by assuming 

 that the shales were deposited under salt water and retaining a portion 

 of the same, the salt of which has since been dissolved by perco- 

 lating waters, and is brought to notice when the wells are drilled. As 

 almost every shale bed from the Mississippian to the Cottonwood 



*Geol. aud Miu. Reisources of Kaus., 1893, p. 43. 

 tUoc. cit. 



