GEO101C Earth Science
Colorado State University Global
The geology of the world has produced some of the most fascinating stone formations that seem to defy explanation. Some of these formations took thousands and even millions of years to form. Rock formations are isolated, exposed bedrock or ancient deposits on the earth’s surface (Neuendorf, Mehl & Jackson, 2011). They are typically created as a result of weathering and erosion which sculpted the stone of long periods of time. These structures can be created in any rock type: igneous, metamorphic, and sedimentary. From pillars of stone jutting skyward to windows through hundreds of tons of rock, stone formations litter the earth telling stories of the past and baffling the imagination.
The rock formation I have selected for this report is called Delicate Arch. The Delicate Arch is located in Arches National Park, Utah. It is a 52 foot tall, free standing natural arch and is the most recognized landmark in the park (Graham, 2005). The arch has gone by many names over the years. The shape of the arch earned it the names of “the Chaps” and “the Schoolmarms Bloomers” (Green, 2011). Names like this were given by local cowboys and ranchers, but there were many other names that the arch was given: “Bloomers Arch”, “Marys Bloomers”, “Old Maids Bloomers”, “Pants Crotch”, “Salt Wash Arch”, and “School Marms Pants” (Hoffman & Mendonca, 1981). The current name, Delicate Arch, was given by Frank Beckwith, leader of the Arches National Monument Scientific Expedition, while exploring the area in the winter of 1934 (Hoffman & Mendonca, 1981).
The arch is formed from Entrada Sandstone. The dark reddish color of the sandstone comes mainly from the mineral hematite (University of Utah, 2018). The National Park Service (2020) tells us that the story of the arch begins some 65 million years ago. During that time the area was nothing more than a dry seabed (National Park Service, 2020). This was also before the breakup of Pangea. The area we now know to be Utah used to be a lot closer to the equator, and when the plates began to drift away from each other, coastal waters found their way through the region, carving its path as it went. Water has done the most, carving out the arches and windows, eroding the soft sand and washing it away
The thing that probably makes this arch so noteworthy is the fact that this structure sits alone at the top of a “bowl” overlooking the vast park. In the picture, it appears that the arch is sitting right on the edge of a cliff, and that’s because it is. It is like looking through a portal; it may not transport you physically but the millions of visitors to this location can all agree that it definitely transports your spirit. Delicate Arch. NPS/Neal Herbert
Additionally, the sheer size of this formation is a wonder to behold. Standing under the arch, 52 feet doesn’t feel right as the arch looks and feels like it is much taller.
Graham, J. P. (2005). Arches National Park: Geologic resource evaluation (pp. 1-64) (U.S., National Park Service, U.S. Department of the Interior). Denver, CO: Geologic Resources Division, U.S. Department of the Interior.
Green, S. M. (2011). Best easy day hikes. Guilford, CT: Falcon Guides.
Hoffman, J. F., & Mendonca, F. L. (1981). Arches National Park: An illustrated guide and history. San Diego, CA: Western Recreational Publications.
National Park Service. (2020, April 9). Geologic Formations. Retrieved May 21, 2020, from https://www.nps.gov/arch/learn/nature/geologicformations.htm
Neuendorf, K., Mehl, J., & Jackson, J. (2011). Glossary of Geology (5th ed.). Alexandria, VA: American Geosciences Institute.
University of Utah. (2018). Entrada Sandstone. Retrieved May 21, 2020, from https://sed.utah.edu/Entrada.htm