Palma fossile (Sabalites sp.)

Fossil palm (Sabalites sp.) Imprint in slab, ca. 48.5-53.5 million years old, U.S. Fossil 140x130x7 cm Provenance: market (Italy) Conservation status. Surface: 65% (color additions where necessary along the fossil footprint) Conservation status. Support: 85% (consolidated state) Sabalites is an extinct genus of palm. Species belonging to the genus lived from the Late Cretaceous to the Miocene and have been found in South America, North America, Europe, and Asia. The genus is characterized by costapalmate leaves, which open in a radial fan with pronounced midribs. The rare fossil, a witness to a climatic situation very different from that of today, dates to the Paleogene, middle Eocene, Lutetian stage and was excavated in the Green River Formation, near Lincoln, Wyoming. The Green River Formation (Green River Formation) is an Eocene geologic formation that records sedimentation in a group of intermontane lakes in three basins located in the United States along today's Green River in Colorado, Wyoming and Utah. The sediments are deposited in very thin layers, a dark layer during the growing season and an inorganic light-colored layer in the dry season. Each pair of layers is named varva and represents a year. The sediments of the Green River Formation show a continuous record of six million years. The average thickness of a varva here is 0.18 mm, with a minimum thickness of 0.014 mm and a maximum of 9.8 mm. Notably in Lincoln County, west of Gosiute Lake, Wyoming, lies a portion of the formation known as Fossil Lake because of the abundance of exceptionally well-preserved fossil fish.