EASTERN AND SOUTHERN UNITED STATES. 
133 
South Carolina. 
The Tertiary deposits of this State occupy considerably more than one-half the 
superficial area, the territory comprised by them having a pretty nearly uniform width 
of 100-110 miles. The inner boundary line (as indeed is the case for almost the 
whole Atlantic border) conforms generally with the coast contours, and crosses the 
State in an almost direct northeast conrse from about opposite Augusta, in Georgia, via 
C'olumbia, to the North Carolina frontier. Throughout its entire extent the formation 
abuts upon granite or metaniorphic rocks, gneisses, schists, and slates, whose exposures 
mark the first or lowest falls of the descending streams. The line of junction of the 
rocks of this series, consisting of sands, clays, marlites, and compact siliceous shell 
conglomerates, or “ buhrstones,” with those of the Archaean series, is indicated along the 
entire distance by deposits of sandy strata, which mark the line of distribution of the 
long-leaved pine {Pitius palustris), and support a vegetation essentially distinct from 
that of the rest of the State. 
Eocene. — Mr. Tuomey* recognizes three distinct divisions in this formation, 
respectively in the order of their position, beginning with the oldest, the Buhrstone, 
the “ Santee beds,” and the “Ashley and Cooper beds,” the last two principally of a 
calcareous character, and corresponding to the “Carolina bed” of Ruffin. They form 
the basement of the so-called “Charleston Basin.” The Buhrstone occupies the inner 
area of the Tertiary formation, extending over a continuous tract between the 
Savannali River and the Congaree, northwest of a sinuous line connecting Lower 
(Upper) Three Runs and Vance’s Ferry on the Santee and passing on the inside of 
Allendale, Barnwell and Orangeburg. The thickness of this formation, which at 
many points along its southern edge and elsewhere can be seen to dip beneath or 
underlie tlie Santee beds, has been stated by Tuomey to be upwards of 200 feet, or as 
much as 400 feet. Its upper member is frequently a layer of greensand, which may 
be the representative of the similar layer that further to the south, in Alabama and 
Mississippi, marks the position of the true “ Claibornian.” However this may be, it 
is practically certain that the Buhrstone of Tuomey and the greensand together 
represent a very considerable, if not the greater portion of the deposits which in this 
State underlie the horizon of the typical “ Jacksonian,” as the character of the con- 
tained organic remains clearly indicates. Their approximate equivalency with the 
Buhrstone and ‘ ‘ Claibornian ” may therefore be assumed. Whether the calcareous strata 
occurring on the Santee below Vance’s Ferry, and bordering upon the southern edge 
of the Buhrstone, be also referable to the “ Claibornian ” or not, or whether they 
constitute the correspondent of the “Jacksonian,” we have as yet no satisfactory 
means of determining. It is true that a general similarity exists between their fossil 
remains and those of the older strata, yet there are a considerable number of forms 
» Report of tlie Geology of South Carolina, 1848. 
18 JOUR. A. N. S. PHILA., VOL. IX. 
