12 KANSAS ACADEMY OF SCIENCE. 



METAMORPHIC DEPOSIT IN WOODSON COUNTY. 



BY PROF. B. F. MUDGE, A. M. 



Much excitement has existed for a year past in Woodson county, Kansas, 

 in relation to the alleged mines of gold and silver at Belmont. These re- 

 ports induced me, in June, 1879, to visit the spot, in company with Prof. Hay. 

 We found evidence of metamorphic action which I had never before seen in 

 Kansas, except at the lead mines in the subcarboniferous deposits in the 

 southeastern part of Cherokee county. The area under consideration is in 

 the coal measures, and is nearly one mile long and one-third as wide. This 

 lies in sections 29 and 32, town 26, range 15, east. Outside of this small 

 area, the lime shales and sandstones in all directions remain unaltered. Some 

 twenty shafts have been opened in the vain attempt to find valuable ores. 

 These enabled us obtain a most accurate knowledge of the metamorphic 

 action. I saw no rock which indicated that the changes observed were 

 caused by the direct action of fire. The moderate metamorphism was, in 

 my estimation, clearly caused by the action of warm mineral salicious waters, 

 and probable under-pressure. The change was most marked on the porous 

 sandstones, and less so on the limestones and clay shales. The vapors and 

 hot waters had expelled a portion of the calcareous material of the lime- 

 stone, and hardened it, by replacing the lost matter with silica. This de- 

 stroyed the fossils only in part, but gave it a black, basaltic appearance. The 

 clay shales had assumed a more granular appearance, interspersed with small 

 flakes of mica. We saw over thirty feet of this stratum in several places. 



But the most marked metamorphic action was seen in the common sand- 

 stone. Its porous character allowed the hot steam and vapor to penetrate 

 freely into all portions of the stratum. At the western portion, near the 

 center of the northwest quarter of section 32, this is seen in blocks of quartz- 

 ite, about a foot in diameter, and three or four feet long. These lie on the 

 surface, evidently left by the denudation of a portion of the stratum. About 

 half a mile farther east, where several good-sized shafts are opened, the 

 changes by metamorphic action could be studied in all their details. On 

 the surface were masses of quartz containing clear, glassy crystals, and at 

 one spot quite a number of specimens of beautiful amethyst. This is the 

 first locality of the latter mineral I have found in Kansas. 



Here, in a large shaft, about thirty feet deep and nearly as long, can be 

 seen the most varied changes. After penetrating five feet of .loose surface 

 material, we have at one edge of the shaft eighteen inches of unaltered red 

 sandstone; below which it is soon altered to a dark-blue chert, and again to 

 pale blue, then cloudy, and finally to a nearly pure white, fine-grained, hard 

 quartzite. In the latter were small spots of carbonate of lime, which could 

 be scratched by the finger-nail. In one side of the shaft, the sandstone as- 



