Ichnofaunas from the Triassic-Jurassic Boundary Sequences of the Gateway area, Western Colorado: Implications for Faunal Composition and Correlations with Other Areas

摘要: Large fossil footprint assemblages have been recovered from the Chinle Group and overlying Wingate Formation, of Dolores Valley canyonlands near Gateway, Colorado. Current evidence suggests that all many lower Formation are Late Triassic in age, but upper ichnofaunas probably Lower Jurassic. Evidence for mammal non-mammalian synapsid-like tracks is equivocal, synapsid eolian abundant strongly suggestive significant facies control (i.e., synapsid-eolian association similar to found older younger deposits). Currently a great imbalance exists between lack ichnotaxonomic names assigned northern hemisphere Mesozoic mammal-like plethora names, some dubious value, southern hemisphere. The problems inherent this discussed context triple influ...