| OCR Text |
Show 173 3.9.2. Tracks and the K-T boundary interval has been inferred to The K-T North Horn Mountain on floodplain represent the abundance no or (Figures 3.8A, are 3.11 were boundary as dinosaurs are are found as the Unit 2. Rocks that has been were the substrate difference, but deformed Unit 1 occur high reported in other Western Interior present in central Utah and only previous cm occurrence tracks in Unit 2A in diameter, about 4 m tracks below the (Lockley, abundant until very stratigraphic levels where occur Undulating Valley (Figure 3.100), and and Hunt, ambiguous about 15 are below similar to those such 1995a). at North Horn Mountain also m tracks sandstone bedforms highest eggshells (Loope, 1986; Lockley undulating forms in Unit 2A at Figure 3.8A) 2A. close to the in Unit 2A demonstrates that evidently occur as areas evidence of dinosaurs. Less highest eggshells in Unit only a Horn tracks have not been documented associated with tracks in Joes elsewhere during B). approximately 60 the level of the that excellent track record made in the semiarid environment. typical of trampling in shortly before the K- T boundary. The were were due to 1991; Lockley and Hunt, 1995a), track that an 1999). The extensive, during deposition of tracks that quite possibly Although the North eggshells and Ekdale, produced existed longer clarity of those sandstone beds that large within Unit 2 of wetlands/lacustrine environment of Unit 2A do not contain the These contrasts K-T (Oifley conditions that deposition of Unit 1 occur the basis of the disappearance of Cretaceous and the appearance of Paleocene fossils semiarid Boundary occur are The recognized highest in the same bed |
