INTERPRETATIONS UK THE CONDITIONS 455 



abimdant vegetation grew prevailed. Sinking incident to the consoli- 

 dation of file underlying 5,U00 feet of Devonian sediments and to crustal 

 warping kept the land near sealevel while the Price was being deposited. 

 During Pulaski time subaerial sedimentation continued in the southern 

 area and the southern shoreline of the Appalachian Sea lay north of 

 Cloyds Mountain. 



In the Xarrows area, originally 30 miles to the north, subaerial con- 

 ditions of sedimentation ceased after 300 feet of sandstone, shale, and 

 coal had been formed. The sea then advanced from the north and lime- 

 stone-forming conditions began. During the deposition of 1,200 feet of 

 limestone of the Greenbrier sedimentation was nearly uniform, but fol- 

 lowing this the shoreline again retreated from the south, the water be- 

 came turbid at intervals, and alternating sands, muds, and calcareous 

 deposits about 1,300 feet thick were deposited. With the beginning of 

 Hinton time the shoreline retreated to north of Xarrows and subaerial 

 sedimentation began. Most of the 1,200 feet of sandstones and shales 

 of the Hinton in the Xarrows region were deposited landward from the 

 sea margin, but the sea advanced to the southward and again retreated 

 several times during the age and thin layers of marine strata interwedgc 

 with thick beds of continental. 



The Price and Pulaski of the Cloyds Mountain region are assumed 

 to be part of a great delta because : 



1. They reach their maximum thickness here and thin rapidly north, 

 east, and west. 



2. For the most part they are clearly subaerial deposits. 



3. The margin of the sea was only a few miles to the north during 

 most of Pulaski time, and conditions here must have been similar to 

 those of the present Mississippi delta near the sea margin. 



According to this hypothesis the Pulaski, Bluefield, Greenbrier, and 

 Hinton of the northern area are to be correlated with the Pulaski of the 

 southern. Stevenson believed this to be true, but M. R. Campbell'' 

 thinks that conditions in the Cove region in W3^the County entirely dis- 

 prove such a correlation. In this region the Greenbrier rests directly on 

 the Pulaski, but the evidence is entirely negative as to whether any of 

 the Greenbrier is of the same age or younger than the Pulaski. 



Conclusions 



]. During Mississippian time the region of Cloyds Mountain, Vir- 

 ginia, was part of a great delta and was generally the site of subaerial 

 deposition. 



• BuU. Geol. Soc. America, vol. 5, p. 178. 



