“…Graywacke and tuff are present locally in the central part (Chapman and others, 1964;Jones and Grantz, 1964;Patton and Keller, 1954;Tailleur, 1954, 1964). The only good exposures for this part of the Jurassic are in northeastern Alaska (Brosge and Tailleur, 1970;Detterman, 1973;Gryc, 1951;Gryc and Mangus, 1954;Keller and others, 1961;Leffingwell, 1919;Reiser and Tailleur, 1969;Reiser and others, 1970;Sable, 1965;Whittington and Sable, 1954), where a major middle Bajocian to early Bathonian unconformity can be detected both lithologically and paleontologically (Imlay, 1955(Imlay, , 1970. Elsewhere in northern Alaska, the rocks are too poorly exposed to determine the presence of unconformities.…”