732 C. 0. Dunbar — Stratigraphy and Correlation 



Aet. XXXVII. — Stratigraphy and Correlation of the 

 Devonian of Western Tennessee 1 ; by Cael 0. Dtjnbae. 



Inteoduction. 



For more than half a century the Devonian of western 

 Tennessee has offered one of the most inviting fields to 

 the stratigrapher and paleontologist, yet the list of pub- 

 lications relating to it comprises little more than a score 

 of pages. It remains to-day the last important area of 

 Lower Devonian in America to be adequately described. 

 These strata are not only replete with finely preserved 

 fossils, but they form the most complete and complex 

 Lower Devonian sequence in the Mississippi Valley 

 province, and the previously unsuspected occurrence here 

 of the typical upper Oriskany gives to the Tennessee area 

 the highest interest. 



Previous studies. — The presence of the Helderbergian 

 rocks in Tennessee was first noted by Safford in 1855, 

 and in 1869 he more fully described these beds, to which 

 in 1876 he and Killebrew applied the name Linden. In 

 1899 a second Devonian formation, the Camden chert, 

 was made known by Safford and Schuchert, who assigned 

 it to the lower Oriskany. Foerste in 1901 defined the 

 Pegram limestone, and in his valuable paper on "The 

 Silurian and Devonian Limestones of Western Ten- 

 nessee'' (1903) he more fully described the Camden and 

 the Linden formations and subdivided the latter into two 

 members, the Ross and Pyburn limestones respectively. 



Scope of the present paper. — This paper is an abstract 

 of a report on the Devonian of Tennessee which will be 

 published at a later date as a bulletin of the Tennessee 

 State Geological Survey. In the complete report the 

 stratigraphic relations and f aunal characteristics of each 

 of the Devonian formations will be described in full, and 

 detailed geologic sections of the important exposures will 

 be given. The limits of the present paper will permit 

 only a brief description of these formations and a 

 presentation of the essential conclusions reached. The 

 new species appearing in the faunas will be described 

 elsewhere at an early date, and the manuscript names are 

 therefore used in this article. 



1 Published by permission of the Tennessee State Geological Survey. 



