THE 



JOURNAL OF GEOLOGY 



SEPTEMBER-OCTOBER, 1903 



THE NOMENCLATURE OF THE OHIO GEOLOGICAL 



FORMATIONS/ 



INTRODUCTION, 



The great advance in stratigraphical geology during the 

 last fifteen years, together with the more precise and accurate 

 description of geological formations, will lead, in most states, 

 to a revision of the geological scale. The effect of this advance 

 in the science was shown in New York, the classic state in 

 American geology, when four years ago Dr. J. M. Clarke and 

 Mr. Charles Schuchert published a revised classification of the 

 geological formations of that state. ^ Most of the changes pro- 

 posed by these distinguished authors have been accepted by 

 working geologists and are now becoming a part of American 

 geology. 



At about the same time the writer began an investigation of 

 the Ohio formations, but the work has not yet reached the 

 desired completeness and accuracy; and, as will be seen by ref- 

 erence to the geological scale, in the case of certain formations 

 a definite classification cannot be proposed until the information 

 is more complete. 



The advance in our knowledge of the stratigraphical geology 

 of the state, together with the introduction of a considerable 

 number of new names for different formations and the approach- 



'This article has been read by Professor Edward Orton, Jr., state geologist of 

 Ohio, and it is published with his permission, 



'Science,!^. S., Vol. X (December 15, 1899), pp. 874-78. The article was reprinted 

 in the American Geologist, Vol. XXV (February, 1900), pp. 114-20. 

 Vol. XI, No. 6. 519 



