Appekunny Formation Explained

48.8364°N -113.654°WAppekunny Formation is a thick series of rock strata located in the Lewis Range within Glacier National Park, in the U.S. state of Montana. The formation is primarily mudstone and siltstone deposited in a shallow sea during the Proterozoic. Not far from the eastern entrance to the Going-to-the-Sun Road at St. Mary, Montana, the formation can be easily seen on the slopes of Singleshot Mountain.^[1] The Appekunny Formation contains bedding structures which may include the remains of the oldest metazoan (animal) on Earth known by the species name Horodyskia moniliformis.^[2]

The Appekunny Formation is named after Apikuni Mountain and averages thick. The rock strata have been dated at between 1.2 - 1.4 billion years old.

Further reading

• Book: Raup, Omar. Robert L. Earhart . James W. Whipple . Paul E. Carrara . Geology Along Going-to-the-Sun Road, Glacier National Park, Montana. Glacier Natural History Association. West Glacier, Montana. 1983. 0-934318-11-5.
• Web site: Price. Mike. January–March 2006. Virtual Geomorphology. 2006-04-29. https://web.archive.org/web/20060515022528/http://www.esri.com/news/arcuser/0206/files/virtual.pdf. 15 May 2006 . live.

Notes and References

1. Web site: Dyson. James. The Belt Formations. The Geologic Story of Glacier National Park. National Park Service. May 27, 2018.
2. 10.5479/si.00810266.94.1 . Middle Proterozoic (1.5 Ga) Horodyskia moniliformis Yochelson and Fedonkin, the Oldest Known Tissue-Grade Colonial Eucaryote . 2002 . Fedonkin . Mikhail A. . Yochelson . Ellis L. . Smithsonian Contributions to Paleobiology . 94 . 1–29 .