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GEOLOGY OF NORTH CAROLINA. 
large territory in the Gulf States, in the Rocky Mountain region and in 
California. 
To this group are referred all the formations which contain, in a fossil 
form, any of the plants or animals now living. Its accumulations of 
more or less indurated sand and clay, marls, shell beds and lignites reach, 
in some places, a thickness of six or eight thousand feet. Coal of an in- 
ferior quality called lignite, or fossil wood, is found in these formations 
in the Rocky Mountain region. The system is subdivided into three 
subordinate groups called Eocene, Miocene and Pliocene. It is found, 
in some of its divisions, in British America as far north as the Arctic 
sea, and also in Greenland, carrying in both, an abundance of fossil plants, 
similar to many which are now living in North Carolina and southward. 
Tertiary rocks abound in other parts of the world, in southern England, 
in France, (as the famous Paris Basin), and in central and southern 
Europe, in the Pyrenees and some of the higher Alps. They cover also 
extensive tracts in Asia, India, China and Japan, and in Egypt. The 
period during which these formations were deposited is called the Age 
of Mammals , on account of the great abundance of fossils and bones of 
many species of this class of animals, as the camel, horse, rhinoceros, 
■elephant, mastodon and many other strange forms having but little re- 
semblance to any living species. 
It is evident that the topography of the continent has undergone vast 
■changes, especially since the Cretaceous age, during which deep sea sedi- 
ments were accumulated several thousand feet thick over a large part of 
the area now lifted into the great ranges and table lands of the Rocky 
Mountains. The character of the Tertiary sediments shows that these 
mountains and plateaus were elevated in part during their deposition, a 
large proportion of them being of fresh water origin, and the great coal 
'beds having been deposited in wide marshes and lagoons. 
The major part of the eastern side of the continent was dry land dur- 
ing the deposition of the Tertiary, which appears therefore only as a 
fringe on its eastern and southern borders, and occurs on and very near 
the surface in its two lower members, over considerable part of the 
eastern division of North Carolina, furnishing nearly all the calcareous 
marls of this region. 
QUATERNARY SYSTEM. 
At the close of the Tertiary period, the physical condition of the earth 
seems to have undergone a great revolution, so that the sub-tropical cli- 
mate and products which extended over the northern portions of the con- 
