| Chunk of petrified wood from the Shinarump Conglomerate Member of the Upper Triassic Chinle Formation, collected just west of the Dinosaur National Monument Boundary, Utah. The specimen is likely fossil driftwood from one of three large trees that were abundant during the Late Triassic age: the conifers Araucarioxylon, Woodworthia, or a peculiar genus called Schilderia--all three of which are known from the Petrified Forest Member of the Chinle Formation at Petrified Forest National Park in Arizona. More than likely, though, it is Araucarioxylon, the most abundant representative of petrified wood in the Chinle Formation. E-mail at Waucoba4@aol.com |