ANIMAS FORMATION DINOSAURS
Lucas et al. stated that because the Paleocene fossil leaves and palynomorphs of the Animas Formation were from levels stratigraphically
above reported dinosaur fossils, these dinosaurs may not be Paleocene in age.
The Animas Formation was first described in detail by
and was originally assigned a Paleocene age based on fossil leaves (Knowlton,
1924); this age was later confirmed based on palynomorphs (Newman,
1987). Neuman not only stated that his studies indicated that the Animas was Paleocene; he further stated that palynologic evidence indicated that the lowermost Paleocene was missing from the Animas Formation. The Animas is a lithologically consistent and distinct unit containing diagnostic volcaniclastic rock fragments that clearly distinguish it from the underlying Cretaceous Kirtland Formation strata.
Reeside (1924) stated that the basal Animas Formation of the northern San Juan Basin was equivalent in age to the "Tertiary (?)" Ojo Alamo Sandstone of the southern part of the basin. With no evidence to refute the Paleocene age of the entire Animas Formation, the dinosaurs of the Animas can only be assumed to be Paleocene.