148 
GEOLOGY OF NORTH CAROLINA. 
Tar River. It is best exposed in the bluffs along the Cape Fear between 
Fayetteville and Wilmington. The rocks of this system (every where 
very slightly compacted) are, for 50 to 60 miles below Fayetteville, sand- 
stones, clay slates and shales, 30 to 40 feet thick, in many places dark to 
black and very lignitic, with projecting trunks and limbs of trees, and 
at a few points, full of marine shells. These beds Dr. Emmons regards 
as probably eocene. For 40 to 50 miles above Wilmington, and in all the 
other river sections, the rock is a uniform dark, greenish gray, slightly 
argillaceous sandstone, massive, and showing scarcely any marks of bed- 
ding. This sandstone every where contains a small percentage of glau- 
conite, and is in fact the representative of the true Greensand. 
The following analysis of a specimen from a representative outcrop at 
Blackrock bluff, 20 miles above Wilmington, on the Cape Fear, is from 
Emmons : 
Silica, 
Oxide of Alumina and Iron, 
Carbonate of Lime, 
Magnesia, 
Potassa, 
Soda, 
Organic Matter, 
Water, 
93.43 
9.00 
11.40 
0.20 
0.38 
0.42 
4.80 
3.80 
100.43 
The above is a fair sample of this formation in all its northern and 
eastern outcrops, as it appears on Tar River, about Kinston, in Lenoir 
county, as well as on South River and Black River, in the southwestern 
corner of Sampson county ; but westward, higher up the Cape Fear, the 
beds lose entirely their glauconitic and calcareous character, and become 
more clayey and frequently black-lignitic, with embedded trunks, limbs 
and leaves of trees ; and not unfrequently it is composed of sandy accu- 
mulations exhibiting much false bedding. These beds extend a hundred 
miles up the Cape Fear from Wilmington. It is probably the same lig- 
nitic member of this series, which appears at low water in the Reuse, at 
the railroad bridge near Goldsboro. The Cretaceous beds of North Car- 
olina are not usually very rich in fossils, the greensand containing gen- 
erally scattered specimens of belenmites, ostraea larva, exogyra costata 
and an occasional anomia ; but at several points on the Cape Fear the 
exogyras are very numerous, and at Kelley’s Cove, about 40 miles from 
