THE TRIASSIC PERIOD 



Mountains. This is in marked contrast with 

 the Paleozoic systems. Accordingly, the 

 present concealed Triassic rocks and areas 

 oi their former presence are pretty largely 

 confined to the immediate regions of exist- 

 ing outcrops. 



Rocks of the Atlantic Coast. — These 

 rocks (Newark series) are seen on the map 

 to occupy comparatively small, narrow areas 

 just east of and parallel to the Appalachian 

 Mountain range from southeastern New 

 York to South Carolina, and farther north- 

 ward in the Connecticut River Valley and in 

 Nova Scotia. In the northern areas the 

 rocks are sandstones and shales, with some 

 coarse conglomerates, especially at the base. 

 Because of their prevailing red color and 

 general resemblances to the "Old Red Sand- 

 stone" (Devonian) of Scotland, they have 

 been called the "New Red Sandstone." 

 Many of the beds show sun-cracks, rain- 

 drop pits, ripple-marks, and foot-prints, and 

 remains of land Reptiles (Dinosaurs). In 

 Virginia and the Carolinas the rocks have 

 a similar lithologic character, though the red 

 color is not so common, and some workable 

 coal beds occur. The fossils, which are 

 mostly plants in the dark shales, point to 

 the Upper Triassic age of the Newark series. 



The rocks of the series are nearly every- 

 where somewhat folded, tilted, and exten- 

 sively fractured by normal faults, and they 

 also contain numerous lava flows, intrusive 

 sheets, and dikes of so-called trap rock (dia- 

 base) (Figs. 120, 121). A remarkable feature 

 is the great thickness of the rocks in these 

 narrow belts, fully 3000 feet in Virginia; 

 7000 to 10,000 feet in the Connecticut 

 Valley; and 10,000 to 15,000 feet in New 

 Jersey. 



Rocks of the Western Interior. — The 

 Triassic strata of the western interior region 

 are distributed over nearly the same areas 



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