BLUE RAPIDS AND GYPSUM CITY DEPOSITS. 



231 



12 feet, soil and shale. 



crushed, the rock becomes snow white. Throughout the Fowler Brothers' 

 mine, northwest of the town of Blue Rapids, there are numerous cut- 

 ters or veins filled with transparent crystals of selenite, often of great 

 perfection. The section at this mine, which is almost the same as at 

 the other mines (see figure 1) shows a limestone bed-rock of blue color 

 more than 4 feet thick. On this rests the gypsum, with an average thick- 

 ness of 8 } feet, covered by 8 feet of red and blue shales, followed by a 

 thin limestone layer and 22 feet r^^^t^^rCtv 

 of buff shales, with another thin ' v vV ^0 



stratum of shaly limestone about 

 the center. One hundred feet 

 above the gypsum occurs a 30- 

 inch stratum of buff fossiliferous 

 limestone carrying a considera- 

 ble amount of flint. This upper 

 limestone occurs throughout the 

 area. 



To the east of the Great West- 

 ern mine, located north of the 

 town, the Cottonwood Falls lime- 

 stone is found about 20 feet 

 below the gypsum horizon. The 

 dip of the gypsum is slightly 

 north of west, about 10 feet to 

 the mile. 



6 inches, shaly limestone. 



io feet, buffshale. 



io inches, limestone. 



6 feet, blue shale. 



8 inches, red shale. 

 20 inches, blue shale. 



8% feet, gypsum. 



4 + feet, blue limestone. 

 Figure r.— Section of Fowler Brothers' 1 Mine. 



Gypsum City Deposits. 



There are three well marked 

 gypsum rock horizons in the 

 central Kansas area. The lower 

 and more extensive deposit ex- 

 tends over the central, northern, 

 and western portions of the area; 

 the second one over the central and southern parts, while the third is 

 only found in a limited area in the southern part. The interval between 

 the middle and lower deposits is 100 feet and between the middle and 

 upper 40 feet. The dip of the three is south of west, with an average 

 of about 6 feet to the mile. 



In the northern part of the area, 6 miles southwest of Solomon City, 

 on the bank of Gypsum creek, is located the mill and mine of the Crown 

 Plaster Company. A section of the hill at the mine, represented in fig- 



