OUTLINES. 
141 
If the rocks of the Smoky or Cherokee belt are not Silurian, the 
formation is wanting in North Carolina. 
TRIASSIC. 
There are in this State two narrow fringes of an eroded and obliterated 
anticlinal, which belong to this system; the smaller, or Dan River belt, 
from 2 to 4 miles wide, following the trough-like valley of that stream, 
(about N. 65° E.), for more than 30 miles, to the Virginia line ; the other, 
the Deep River belt, extending, in a similar trough, 5 to 15 miles wide, 
(and depressed 100 to 200 feet below the general level of the country), 
from the southern boundary of the State, in Anson county, in a N. E. 
direction, to the middle of Granville county, within 15 miles of the Vir- 
ginia line. They are separated, therefore, by a swell of country 100 to 
75 miles wide, which rises along its topographical axis to 8 or 900 feet 
above the sea, the troughs themselves having respectively an elevation of 
5 to 600 feet and 2 to 300 feet. The belts are convergent in the direction 
of the Triassic beds of Virginia, with which they were doubtless once 
connected, (as well as with some small intervening outliers) in one con- 
tinuous formation. 
The dip of the Dan River beds is about 35° N. W., (20° to 70°) and 
of those of Deep River 20° S. E., (10° to 35°). The rocks are sand- 
stones, clay slates, shales and conglomerates, generally ferruginous and 
brick-red, but often gray and drab. The shales are occasionally marly, 
and these and the sandstones are sometimes saliferous. Many of the 
beds consist of loose and uncompacted materials, and are therefore easily 
abraded. 
The most important and conspicuous member of the series, is a large 
body of black shales, which encloses seams of bituminous coal, 2 to 6 
feet. This coal lies near the base of the system in both belts, and is un- 
derlaid on Dan River by shales, and on Deep River by sandstones and 
conglomerates ; the latter constituting the lowest member of the series, 
and being in places very coarse. And near the eastern margin in Wake 
county, where the belt reaches its greatest breadth, (some 15 miles,) the 
conglomerates are of great thickness and very coarse, uncompacted and 
rudely stratified, resembling somewhat the half-stratified drift of the 
mountain slopes, the fragments often little worn and sometimes 10 and 
12 inches in diameter, and evidently derived from the Huronian rocks of 
the hills to the eastward. The conglomerates of the Dan River belt are 
among the upper members of the series, and are mostly fine and gradu- 
ation to grits and sandstones. 
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