4l8 ABSTRACTS 



After a description ot the broader features of the Appalachian 

 province, the local geography is analyzed. The various types of 

 surface features are pointed out, and their relations to the underly- 

 ing rocks are shown. Local phenomena such as elevations and the 

 details of the drainage which is effected by the Nolichucky, French, 

 Broad, Holston, and Clinch rivers, tributaries of the Tennessee, are 

 detailed. 



Under the heading "Stratigraphy" the geologic history of the 

 Appalachians is presented in outline. This is followed by a detailed 

 account of the local rock groups, in regard to their location, composi- 

 tion, thickness, variations, and mode of deposition. The soils and 

 forms of surface produced by each formation are discussed with the 

 formations. Twenty formations ranging from Cambrian to Carbon- 

 iferous, are distinguished in this quadrangle ; the greater portion being 

 Cambrian and Silurian. The rocks of Carboniferous and Devonian 

 age are found only in two narrow belts in the ridge district, and are 

 represented by only four formations. Over the rest of the area Cam- 

 brian and Silurian strata are about equally represented. A gjeat 

 variety of limestones, shales, and sandstones compose the -Cambrian^ 

 and Silurian rocks. Shales and sandstones make up the Devonian, 

 while only the limestone appears in the Carboniferous. Great changes 

 take place in the Silurian strata; limestones on the northwest being 

 represented by shales and sandstones at the southeast. The general 

 character of the formations is graphically represented in the columnar 

 sections, one being drawn for each of the two chief geologic districts. 



In the discussion of structure, after a general statement of the 

 broader features of Appalachian structure, the two types of deforma- 

 tion shown in this region are described, and illustrations are pointed 

 out in the structure sections. In the ridge district the most prominent 

 feature is the faulting, which has cut the strata into long narrow blocks 

 and produced the characteristic ridge topography. Southeast of Hol- 

 ston River the rocks were deformed by close folds. Deformation by 

 vertical uplift is also present, but it can only be observed in compari- 

 son with other and larger areas. In the structure sections, most of 

 the details of the different structures are shown. 



Economic products of this region are marble, building stone, lead, 

 zinc, cement, clays, and timber. The outcrops of the formations 

 containing these are represented on the economic sheet as far as pos- 

 sible, together with the locations of mines and quarries. The principle 



