File:Cf. Sabal (fossil palm frond) (Laramie Formation, Upper Cretaceous; Parfet Prehistoric Preserve, Golden, Colorado, USA) 2.jpg

English: Fossil palm frond (cf. Sabal) in sandstone in the Cretaceous of Colorado, USA.

Seen here is a fossil palm frond exposed on the underside of a tectonically-tilted sandstone bed in Golden, Colorado. This is an old clay mine - soft clay horizons occurred between hard sandstone intervals of the Laramie Formation. The beds here are vertically oriented - structural tilting occurred during the Laramide Orogeny in the Tertiary. The Laramie Formation is a nonmarine, coastal plain to deltaic succession of mostly mixed siliciclastic sedimentary rocks - sandstones, siltstones, claystones, and coals.

After clay mining ceased, the site became a landfill for ash from coal burning operations. Landfill activity buried many dinosaur footprints preserved in the Laramie Formation sandstones. The locality is now a "fossil preserve" with dinosaur footprints, plant fossils, and other features that can be closely examined along trails. An odd-looking golf course makes up the rest of the old clay mine.

Classification: Plantae, Angiospermophyta, Arecales, Palmae/Arecaceae

Stratigraphy: Laramie Formation, Maastrichtian Stage, upper Upper Cretaceous

Locality: outcrop along Triceratops Trail, Parfet Prehistoric Preserve, southern side of the town of Golden, Colorado, USA (vicinity of 39° 44' 36.83" North latitude, 105° 13’ 10.66" West longitude)