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<br />. <br /> <br />2880 <br /> <br />~le Morrison Formation seems to overlie the Junction <br /> <br /> <br />Creek Sandstone conformably in the project area; however, <br /> <br /> <br />.fluvial channeling occurs locally at the contact. Craig <br /> <br /> <br />and cadigan (1958, p. 185) consider the contact of the <br /> <br />Morrison and the Junction Creek as "* * * characteristically <br />a conspicuous erosion surface suggesting a disconformity <br /> <br />between the Morrison Formation and the Bluff and Junction <br /> <br />Creek Sandstones." They note that where mudstone of the <br />Morrison rests on structureless silty sandstone of the <br /> <br />Junction Creek, the sequence appears conformable and in <br /> <br />places gradational. <br />'l'he upper contact of the unit with the Burro canyon <br />Pormat.ior. of Lower Cretaceous age is quite arbitrary, and <br />a break in sedimentation is not noted between the two units. <br /> <br />~ T11e boundary between the Jurassic and Cretaceous sediments <br /> <br />lS aiscussed on page ~ <br /> <br />Abundant fossil remains, indicating a Late Jurassic <br />age, have been found in the Morrison in many places. <br /> <br />. <br /> <br />foo <br />