SYSTEM Divaric Series 1 Scythic Series The Pacific Coast beds are marine, while those of the Atlantic border are estuarine. In the Eastern States the Triassic formation consists of a series of sandstones and shales extending more or less unbrokenly from the Connecticut Valley to South Carrolina. The rocks were de posited in shallow water along the continental shores. The Newark rocks are in many places faulted and intruded by igneous rocks, the erup tions having in some cases occurred while the deposition of sediment was still going on, be ing thus in the nature of submarine outbursts. The Palisades of the Hudson River and the East Rock at New Haven, Conn., are formed of dia base erupted during the Triassic period. Some doubt exists as to whether the Triassic rocks of the Atlantic border were one continuous belt or whether they were deposited in separated troughs. In the interior of the continent along the Rocky Mountains there are extensive beds of red sandstone which were deposited in an in land sea, but whether they belong to the Triassic or Jura-Trias is unsettled. On the Pacific Coast the Triassic rocks have a maximum thickness of nearly 5000 feet. Triassic rocks are known in Central and South America, Europe. Asia, and Australasia.
The plant life of the Triassic included ferns, cyeads, conifers, and gigantic representatives of the Equiseta or horsetails. Tha accumulated re mains of these plants contributed to the for mation of important coal seams. Among the vertebrates fishes were fairly abundant, the domi nant type being ganoids; but the most character istic class was the Amphibia, which attained its greatest development in this period. Of reptiles
the ichthyosaurs, plesiosaurs, dinosaurs, croco diles, and turtles were present, while the earliest representatives of the Mammalia came into ex istence.
The Triassic beds of the Atlantic border yield great quantities of sandstone (brownstone) for building, which has been quarried chiefly Connecticut Valley and New Jersey. De posits of coal are found in the Triassic of Vir ginia and North Carolina and in parts of Europe, but they are of minor importance compared with the great coal measures of the Carboniferous age.
BIBLIOGRAPHY. Kimmel, "The Newark Rocks Bibliography. Kimmel, "The Newark Rocks of New Jersey and New York," Journal of Geol ogy, vii., pp. 23-52: Staler and Woodworth, "Geology of the Richmond Basin, Virginia." IVineteenth Annual Report of United States Geo logical Survey, part ii., p. 325; Russell. "The Newark System," Bulletin 85, United States Geo logical Surrey; Dalton, "The Relations of the Traps of the Newark System in the New .Jersey Region." Bulletin d7, United States Geological Surrey; Davis, "The Triassic Formation of Con nectieut," 18th Annual Report, United States Geological Survey, part ii.. p. 9: Hopkins, "The Brownstones of Pennsylvania," Bulletin Issued by Pennsylvania State College. See GEOLOGY; PALEONTOLOGY; etc.