- Article
Stratigraphic Position and Age of the Upper Triassic Placerias Quarry, East-Central Arizona, USA
- Spencer G. Lucas
The Placerias quarry is a dicynodont-dominated bonebed in Upper Triassic Chinle Group strata near St. Johns in east-central Arizona, USA. Though long identified as being in strata of the lower Chinle Group, recently published numerical ages apparentl...

