I50 NEW YORK STATE MUSEUM 



ORIGIN OF COLOR IN THE VERNON SHALE 



BY W. J. MILLER 



For over 50 years the subject of the origin of colors in rock 

 formations has been much discussed and many explanations have 

 been offered. Of the early papers that by Maw 1 in 1868 is perhaps 

 the most able and comprehensive. In 1879 Julien 2 published a 

 paper which contains a discussion of the origin of red formations. 

 In 1899 Russell 3 ably treated the subject of subaerial rock decay and 

 color origin in certain rocks. His paper gives a good summary of 

 the views expressed by earlier writers. In 1908 Barrell 4 gave an 

 excellent discussion of the origin of such colors in rocks. It 

 is not the purpose of the present brief paper to deal with the 

 phenomena of colors in rock formations in general nor to review 

 the literature, but it is rather to confine attention to' the color 

 phenomena of the well known Vernon red shale of central New 

 York. That the color phenomena in these shales are not merely 

 superficial or due to recent atmospheric action, is proved by the 

 fact that the same features have been found in deep wells passing 

 through the formation. 



The Vernon shale has its type locality in the town of Vernon, 

 a few miles west of Clinton, and it extends from southern Herkimer 

 county westward across the State. Wherever exposed the shale 

 presents a striking appearance due to its red color. A section, in- 

 cluding the Vernon shales, near Clinton is as follows in descending 

 order : 



3 Camillus formation — Dark, thin-bedded shales 



c 5 feet of light green shale 

 & 135 feet of dull red shale, unstrati- 

 fied and with green spots scattered 

 through the mass 

 a 10 feet of light green shale 



1 Niagara formation — Dark shales and sandy limestones. Con- 

 tains large concretions. 



The red shale, with the green bed at its base, is well shown in the 

 ravine just north of Hamilton College and in Kirkland glen nearly 

 2 miles southwest of Clinton. The upper green bed, with the 

 Camillus above and the red shale below, are well exposed at the 

 reservoir 2 miles southwest of Clinton. At the " Dug-way," 2 



1 Geol. Soc. Quar. Jour. Lond. 1868. 24:351-400. 



2 Am. Assoc. Adv. Sci. Proc. 1879, p. 311-410. 



3 U. S. Geol. Sur. Bui. 52, especially p. 44~56. 

 * Jour. Geol. 1908, v. 16.. especially p. 285-94. 



2 Vernon formation 

 (150 feet). 



