• Source: Fountain Formation

The Fountain Formation is a Pennsylvanian bedrock unit consisting primarily of conglomerate, sandstone, or arkose, in the states of Colorado and Wyoming in the United States, along the east side of the Front Range of the Rocky Mountains, and along the west edge of the Denver Basin.




Origin of name


The Fountain Formation was named by geologist C. W. Cross in 1894 for exposures along Fountain Creek in El Paso County, Colorado.




Stratigraphy



The Fountain Formation is found along the Front Range of Colorado. To the north, the Formation unconformably overlies Precambrian granite and gneiss. To the south, it overlies Mississippian, Ordovician and Devonian Limestones, as well as Cambrian sandstones. Outcrops of the formation typically dip steeply to the east.




= Depositional environment

=
The formation was formed by the erosion of the Ancestral Rocky Mountains, and deposition by fluvial processes as alluvial fans. The characteristic predominant red color and the composition of the Fountain reflect that of the granites and gneisses from which it was eroded.




= Notable outcrops

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Flagstaff Mtn Park, near Boulder, Colorado
Flatirons, near Boulder, Colorado
Red Rocks Park and Amphitheater, Morrison, Colorado
Roxborough State Park, south of Denver, Colorado
Garden of the Gods in Colorado Springs, Colorado
Red Rock Canyon Open Space in Colorado Springs, Colorado
Red Canyon Park near Cañon City, Colorado




= Fossils

=
Marine invertebrates have been discovered in a limestone and shale member of the Fountain Formation, cropping out on a low hogback in Perry Park. Invertebrates include bryozoans, brachiopods, crinoids, echinoids, and gastropods.
Plant fossils have been discovered in Garden Park north of Cañon City, including Lepidophloios laricinus, Sigillaria, Syringodendron sp., Lepidophyloides sp., Lepidostrobus sp., Lepidostrobophyllum sp., Calamites, Neuropterus sp., Cyclopteris sp., and Stigmaria ficoides.




Age


Rocks of the Fountain Formation are considered to be of Late Pennsylvanian age, and are between 290 and 340 million years old.




References






External links


Gravmag.com: Geology of the Fountain Formation

Kata Kunci Pencarian:

• Fountain Valley, California
• Dunia Fantasi
• Antarktika
• Kekhalifahan Rasyidin
• Kekaisaran Romawi
• Rasisme
• Analek Konfusius
• Santa Ana, California
• Fountain Formation
• Rich Fountain Formation
• Front Range
• Flatirons
• Red Rocks Park
• Denver Basin
• Red Rocks Amphitheatre
• Lyons Formation
• Garden of the Gods
• Roxborough State Park