i6 



Upon this percentage he rests his proof that these beds are Plio- 

 cene, this being about the percentage of the fossil shells that are also 

 recent, claimed by Lyell and other English geologists as necessary 

 to constitute the Pliocene. 



The post-Pliocene was, in this survey of Tourney's, treated more 

 fully than ever before in the State, and perhaps more fully than this 

 formation had been treated anywhere else along the Coastal Plain. 

 The work of Ruffin was reviewed and several additional localities 

 added to the list of exposures. "It is composed of beds of sand, clay 

 and mud, containing fossils, the whole amounting to about sixty feet 

 in thickness, overlapping the Pliocene beds of Horry and George- 

 town, and on the rest of the coast those of the Eocene." The section 

 of one of the wells that cuts through the post-Pliocene at Charleston 

 shows : 



Sand below which water is found 5 to 6 feet 



Quick sand and clay, remains of trees 9 feet 



Sand and small shells. . 1 foot 



Gravel and oyster shells 2 feet 



Mud and Conch shells 2 feet 



Fine close clay with young oyster shells 3 feet 



Pluff clay with scales of mica, sand to Eocene bed. . . .20 feet 



The following general observations were made: That though 

 the fossiliferous bed in this section is eight feet thick, it is rarely 

 more than four feet thick in its exposures along the coast ; that this 

 is typical of all sections along the coast, the fossiliferous bed being 

 everywhere overlaid by heavy beds of sand, closely similar to those 

 being formed along the coast at present ; that the fossiliferous forma- 

 tion extends back from the coast about ten miles, thinning out at an 

 elevation a few feet above tide; that its boundary is irregular; that 

 this bed underlies the whole coast, and is seen wherever the streams 

 remove the beds by which it is covered. He found the formation 

 exposed on Price's Creek (now called White Point Creek) in Horry 

 County about a half-mile from the beach and elevated five feet above 

 tide. The shells here were principally Venus mercenaria, Ostrea 

 Virginica and Area incongrua. Also in several other places in Horry 

 County and in Georgetown County exposures were found. At 

 Laurel Hill bluff the fossil bed was observed eight feet above tide, 

 and in digging Winyah Canal post-Pliocene shells were met with, 

 showing that the surface sands are underlaid by it. The nature of 

 the formation here was found to be very much like that of the bed 



