The Pennsylvanian section of Kansas and neighboring States is widely known for the essentially unaltered character of the composing sediments and the supposed absence of any effects referable to agents of igneous origin. The discovery, therefore, of evidence which proves that hydrothermal metamorphism has affected sands and sandy shales to the extent of changing them to quartzites is a fact of considerable interest and importance.2
The quartzites occur at Silver City,3 the eastern end of a long east-west ridge in the southern part of Woodson County. This portion of the ridge forms the northeastern flank of a small anticline which for convenience may be given the name of the locality.
For assistance in mapping the structure and working out the geology the writer is indebted to two of his students, Messrs. Milburn Stryker and W. L. Ainsworth. The work was done in the interest of the Fredonia Gas Company, through . . .