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 Generalized Plateau Section

CPCP Section
Figure 2: Generalized Colorado Plateau section (Glen Canyon/Kaiparowits Plateau, based on with the cored sections recommended by the CPCP workshop participants, a generalized evaporation – precipitation (E-P) curve loosely based on climate sensitive facies, and some major geolofical and biological events (* actual boundary may or may not be present in rock section). See Figure 1 for core area abbreviations. Note that the relative thicknesses of various units are in general different than what is shown in the color section and not the same between different coring areas.

The five major stratigraphic units shown abve were deposited under dramatically changing climatic conditions that constitute the Triassic and Jurassic of the Colorado Plateau: the Early to Middle Triassic Moenkopi Formation (marginal marine and coastal sabka to semiarid fluvial and floodplain, minor eolian); the Late Triassic Chinle Group (humid to semiarid fluvial to lacustrine, some eolian near top); the latest (?) Triassic-Early Jurassic Glen Canyon Group (semiarid to arid, major eolian, fluvial, lacustrine); the Middle to Late Jurassic San Rafael Group (marine to coastal sabka, major eolian and fluvial arid to semiarid) (from; and the Late Jurassic Morrison Formation (semiarid to humid, fluvial and lacustrine). Determining the origin of the large climatic transitions represented by these units is a major goal of the CPCP.