. Annual report. New York State Museum; Science; Science. 66 NEW YORK STATE MUSEUM The present surface distribution of the Upper Cretacic beds is much like that of the Lower Cretacic, and they also dip under the still later formations of the Coastal plain (see figure 22). The thickness of the Upper Cretacic is never more than a few hundred Fig. 22 Diagrammatic section through the Atlantic slope, at about the latitude of northern New Jersey, showing the structures and relations of the various physiographic provinces as they now exist. A toB = Folded Paleozoic strata of the Appalachian mo
. Annual report. New York State Museum; Science; Science. 66 NEW YORK STATE MUSEUM The present surface distribution of the Upper Cretacic beds is much like that of the Lower Cretacic, and they also dip under the still later formations of the Coastal plain (see figure 22). The thickness of the Upper Cretacic is never more than a few hundred Fig. 22 Diagrammatic section through the Atlantic slope, at about the latitude of northern New Jersey, showing the structures and relations of the various physiographic provinces as they now exist. A toB = Folded Paleozoic strata of the Appalachian mountains, with hard strata standing out to form the ridges. B to C = Piedmont plateau consisting of highly folded and metamorphosed rocks of Precambrian and early Paleozoic ages. C to E — Triassic strata showing tilting and faulting of the beds and mode of occurrence of an igneous rock sheet (D) which outcrops to form a low ridge. Eto H = Coastal plain, consisting of comparatively thin sheets of uncon- solidated sediments. Eto F= Cretacic beds (upper and lower). F to G'= Tertiary beds. Gto H = Quaternary beds H -— Present coast line. The dotted line represents the peneplain character of the surface (except for the tilting) at the close of the Cretacic period. To summarize: The Cretacic period opened with slight subsi- dence of the Coastal plain region, including southeastern New York, to produce low-lying flats upon which the nonmarine Potomac sedi- ments were deposited. Then came a slight re elevation {accom- panied by erosion) followed by subsidence of the Coastal plain region enough to allow encroachment of the shallow sea in which the Upper Cretaceous sediments were accumulated. LIFE OF THE MESOZOIC The life of the Mesozoic is but scantily represented within New York State because rocks of that age are so poorly exposed. The Mesozoic era is commonly referred to as the " Age of Reptiles " because animals of that class then reached their culmination of. Please no
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