Age dating palm trees
Large herds of animals grazed in this region of grasslands and scattered forests including mastadons, llamas, horses and tapirs.
Today in this parched region of barren, eroded hills and deep gullies, only the bones and petrified wood from this great fauna and flora remain. San Diego Association of Geologists, San Diego, California.
Bridget finds her popularity waning because of her exclusive, long distance relationship with Donny, while Kerry's social status skyrockets because of her relationship with Kyle.
Right: A 50 million-year-old piece of petrified wood (possibly redwood) from nearby Lamar Valley compared with a piece of recent dead wood.
This range contains well-preserved petrified trees that are still in their original upright position.
The trees in the foreground are narrow-leaf cottonwood (Populus angustifolia).
Right: A petrified palm petiole, possibly from a species of Sabal. End view of one of the above wood fragments in its natural state. The fine grain structure shows perfectly preserved tracheids viewed in a transverse (cross section) plane.
Left: Sections of palm petioles from a present-day cabbage palm (S. The cell structure of the petrified sample, composed of scattered vascular bundles without definite annual rings indicates that is was from a palm. "Cretaceous Palynoflora and Neocene Angiosperm Woods From Anza-Borrego Desert State Park, California: Implications For Pliocene Climate of the Colorado Plateau and Age of the Grand Canyon." In: Paleontology and Geology of the Western Salton Trough Detachment, Anza-Borrego Desert State Park, California (Volume I). This wood predates the larger vessels characteristic of angiosperms.